U.S. patent application number 12/943770 was filed with the patent office on 2011-06-23 for link report relay in access division multiplexing systems.
This patent application is currently assigned to TELEFONAKTIEBOLAGET LM ERICSSON (PUBL). Invention is credited to Magnus OLSSON, Goran RUNE, Per SYNNERGREN, Erik WESTERBERG.
Application Number | 20110151874 12/943770 |
Document ID | / |
Family ID | 44150942 |
Filed Date | 2011-06-23 |
United States Patent
Application |
20110151874 |
Kind Code |
A1 |
OLSSON; Magnus ; et
al. |
June 23, 2011 |
LINK REPORT RELAY IN ACCESS DIVISION MULTIPLEXING SYSTEMS
Abstract
Relevant radio-link related information is transferred through a
wireless terminal (30) from type of network (network 22B) to
another type of network (network 22A and vice versa. The wireless
terminal 30 acts as a mediator or relay for the link report message
of one type network (network 22B) so that link indications thereof
can be utilized in a handover determination by the other type
network (network 22A).
Inventors: |
OLSSON; Magnus; (Stockholm,
SE) ; RUNE; Goran; (Linkoping, SE) ;
SYNNERGREN; Per; (Lulea, SE) ; WESTERBERG; Erik;
(Enskede, SE) |
Assignee: |
TELEFONAKTIEBOLAGET LM ERICSSON
(PUBL)
Stockholm
SE
|
Family ID: |
44150942 |
Appl. No.: |
12/943770 |
Filed: |
November 10, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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61287575 |
Dec 17, 2009 |
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61287623 |
Dec 17, 2009 |
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61287438 |
Dec 17, 2009 |
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61287627 |
Dec 17, 2009 |
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61287630 |
Dec 17, 2009 |
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61287954 |
Dec 18, 2009 |
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Current U.S.
Class: |
455/436 ;
455/422.1 |
Current CPC
Class: |
H04W 76/25 20180201;
H04W 72/02 20130101; H04W 60/005 20130101; H04W 36/0022 20130101;
H04W 72/0446 20130101; H04L 5/0055 20130101; H04W 88/08 20130101;
H04W 72/1215 20130101; H04W 88/02 20130101; H04W 88/06
20130101 |
Class at
Publication: |
455/436 ;
455/422.1 |
International
Class: |
H04W 36/00 20090101
H04W036/00; H04W 4/00 20090101 H04W004/00 |
Claims
1. A method of operating a wireless terminal capable of
communicating with a first radio access technology network and a
second radio access technology, the method comprising: the wireless
terminal receiving a link report message from the second radio
access technology network, the link report message comprising an
indication of an uplink quality from the wireless terminal to the
second radio access technology network; the wireless terminal
including an indication of the quality determination in a proxy
link report message and transmitting the proxy link report message
to a node of the first radio access technology network.
2. The method of claim 1, further comprising the wireless terminal
including essentially the entire link report message in the proxy
link report message.
3. The method of claim 1, further comprising the wireless terminal
processing the indication of the uplink quality and including a
processed result as the indication of the quality determination in
the proxy link report message.
4. The method of claim 1, further comprising the wireless terminal
performing interleaved communications with the first radio access
technology network and the second radio access technology network,
and wherein the first radio access technology network and the
second radio access technology network each comprise one of a
Global System for Mobile communication (GSM) network and a Long
Term Evolution (LTE) network.
5. The method of claim 1, further comprising: the wireless terminal
performing a downlink quality determination with respect to the
first radio access technology network and a downlink quality
determination with respect to the second radio access technology
network; the wireless terminal transmitting an indication of at
least one of the downlink quality determinations to the node of the
first radio access technology network.
6. The method of claim 5, further comprising the wireless terminal
including the indication of at least one of the downlink quality
determinations in the proxy link report message.
7. The method of claim 5, further comprising the wireless terminal
including the indication of at least one of the downlink quality
determinations in a wireless terminal separate link report
message.
8. The method of claim 1, further comprising: the wireless making a
determination of signal quality with respect to a third radio
access technology network; and the wireless terminal transmitting
an indication of the signal quality of the third radio access
technology network to the node of the first radio access technology
network.
9. The method of claim 8, further comprising the wireless terminal
including the indication of the signal quality of the third radio
access technology network in the proxy link report message.
10. A wireless terminal comprising: a communications interface
configured to enable the wireless terminal to communicate with a
first radio access technology network and a second radio access
technology network; and a link report processor configured to
receive a link report message from the second radio access
technology network and to prepare a proxy link report message for
transmission to a node of the first radio access technology
network; the link report message comprising an indication of an
uplink quality from the wireless terminal to the second radio
access technology network; and the link report processor being
configured to include an indication of the quality determination in
the proxy link report message.
11. The apparatus of claim 10, wherein the link report processor is
configured to include essentially the entire link report message in
the proxy link report message.
12. The method of claim 10, wherein the link report processor is
configured to process the indication of the uplink quality and to
include a processed result as the indication of the quality
determination in the proxy link report message.
13. The apparatus of claim 10, wherein the communications interface
is configured to perform interleaved communications with the first
radio access technology network and the second radio access
technology network, and wherein the first radio access technology
network and the second radio access technology network each
comprise one of a Global System for Mobile communication (GSM)
network and a Long Term Evolution (LTE) network.
14. The apparatus of claim 10, further comprising: a wireless
terminal measurement unit configured to perform a downlink quality
measurement with respect to the first radio access technology
network and a downlink quality measurement with respect to the
second radio access technology network; and wherein the link report
processor and the communications interface are configured to
transmit an indication of at least one of the downlink quality
measurements to the node of the first radio access technology
network.
15. The apparatus of claim 14, wherein the link report processor is
configured to include the indication of at least one of the
downlink quality measurements in the proxy link report message.
16. The apparatus of claim 14, wherein the link report processor is
configured to include the indication of at least one of the
downlink quality measurements in a wireless terminal separate link
report message which is sent to the node of the first radio access
technology network separately from the proxy link report
message.
17. The apparatus of claim 10, wherein the measurement unit is
further configured to make a signal quality determination with
respect to a third radio access technology network; and wherein the
link report processor and the communications interface are
configured to transmit an indication of the signal quality of the
third radio access technology network to the node of the first
radio access technology network.
18. The apparatus of claim 17, wherein the link report processor is
configured to include the indication of the signal quality of the
third radio access technology network in the proxy link report
message.
19. A radio base station node comprising: a communications
interface configured to transmit uplink transmissions to and
receive downlink transmissions from a wireless terminal; a base
station measurement unit configured to perform a quality
determination with respect to an uplink transmission from the
wireless terminal; a base station link report processor configured
to include an indication of the quality determination in a link
report message to the wireless terminal.
20. A radio access network handover control node comprising: a
control node link report processor configured to receive a link
report message and a proxy link report message; a handover unit
configured to use both the link report message and the link report
message to determine whether to perform handover from the first
radio access technology to the second radio access technology
network; wherein the link report message includes an indication of
a quality measurement regarding a transmission between a wireless
terminal and a node of the first network; and wherein the handover
unit is configured to receive the proxy link report message from
the wireless terminal through the first radio access technology
network, the proxy link report message including an indication of a
quality determination regarding an uplink transmission from the
wireless terminal to a node of the second radio access technology
network.
21. A method of operating a communications system comprising a
first radio access technology network and a second radio access
technology network, the method comprising: a base station node of
the second radio access technology network performing a quality
determination with respect to an uplink transmission from a
wireless terminal; the base station node of the second radio access
technology network including an indication of the quality
determination with respect to the uplink transmission from the
wireless terminal in a link report message transmitted to the
wireless terminal; the wireless terminal including the indication
of the quality determination with respect to the uplink
transmission from the wireless terminal based on the link report
message in a proxy link report message and transmitting the proxy
link report message to a node of the first radio access technology
network; using the quality determination with respect to the uplink
transmission from the wireless terminal as included in the proxy
link report message to determine whether to perform a radio access
technology handover procedure.
22. The method of claim 21, further comprising the wireless
terminal including essentially the entire link report message in
the proxy link report message.
23. The method of claim 21, further comprising the wireless
terminal processing the indication of the uplink quality and
including a processed result as the indication of the quality
determination in the proxy link report message.
24. The method of claim 21, further comprising: the wireless
terminal also providing, to the node of the first radio access
technology network, an indication of a quality determination
regarding a transmission between the wireless terminal and the
first radio access technology network; using the indication of the
signal quality between the wireless terminal and the first radio
access technology network to determine whether to perform the radio
access technology handover procedure.
25. The method of claim 24, further comprising the wireless
terminal also including, in the proxy link report message, the
indication of the quality determination regarding a transmission
between the wireless terminal and the first radio access technology
network in the proxy link report message.
26. The method of claim 24, further comprising the wireless
terminal including the indication of the quality determination
regarding the transmission between the wireless terminal and the
first radio access technology network in a wireless terminal
separate link report message.
27. The method of claim 21, further comprising: the wireless
terminal making a determination regarding signal quality of a third
radio access technology network; the wireless terminal transmitting
an indication of the determination regarding the signal quality of
the third radio access technology network to the node of the first
radio access technology network; and using the indication of the
signal quality of the third radio access technology network to
determine whether to perform the radio access technology handover
procedure.
28. The method of claim 27, further comprising the wireless
terminal including the indication of the signal quality of the
third radio access technology network in the proxy link report
message.
29. The method of claim 27, further comprising the wireless
terminal including the indication of the signal quality of the
third radio access technology network in a wireless terminal
separate link report message.
Description
RELATED APPLICATIONS
[0001] This application claims the priority and is related to the
following United States Provisional patent applications, all of
which are incorporated herein by reference in their entireties:
U.S. Provisional Patent Application 61/287,575 (attorney docket:
2380-1425) to Magnus Olsson et al., entitled "GSM and LTE
Multiplexing Systems", filed on Dec. 17, 2009. U.S. Provisional
Patent Application 61/287,623 (attorney docket: 2380-1426) to
Magnus Olsson et al., entitled "Link report Relay in Access
Division Multiplexing Systems", filed on Dec. 17, 2009. U.S.
Provisional Patent Application 61/287,438 (attorney docket:
2380-1427) to Magnus Olsson et al., entitled "WCDMA and LTE
Multiplexing", filed on Dec. 17, 2009. U.S. Provisional Patent
Application 61/287,627 (attorney docket: 2380-1428) to Magnus
Olsson et al., entitled "Telecommunications Multiplexing", filed on
Dec. 17, 2009. U.S. Provisional Patent Application 61/287,630
(attorney docket: 2380-1429) to Magnus Olsson et al., entitled
"Access Division Multiplexing--Call Setup Performance Improvement",
filed on Dec. 17, 2009. U.S. Provisional Patent Application
61/287,954 (attorney docket: 2380-1433) to Magnus Olsson et al.,
entitled "Scheduled Optimized for GSM and LTD Multiplexing", filed
on Dec. 17, 2009.
[0002] This application is related to the following United States
patent applications, all of which are filed on same date herewith
and incorporated herein by reference in their entireties:
U.S. patent application Ser. No. ______ (attorney docket:
2380-1437) to Magnus Olsson et al., entitled "GSM and LTE
Multiplexing". U.S. patent application Ser. No. ______ (attorney
docket: 2380-1456) to Magnus Olsson et al., entitled "Keeping
Packet Switched Session in LTE While Circuit Switched Registered in
WCDMA". U.S. patent application Ser. No. ______ (attorney docket:
2380-1457) to Magnus Olsson et al., entitled "Maintaining Packet
Switched Session in LTE When Establishing GSM Circuit Switched
Call". U.S. patent application Ser. No. ______ (attorney docket:
2380-1461) to Magnus Olsson et al., entitled "Call Setup For Access
Division Multiplexing". U.S. patent application Ser. No. ______
(attorney docket: 2380-1460) to Magnus Olsson et al., entitled
"Scheduling For Access Division Multiplexing".
TECHNICAL FIELD
[0003] This technology pertains to wireless communications
networks, and particularly to the reporting and/or use of
measurements for such purposes as handover.
BACKGROUND
[0004] In a typical cellular radio system, wireless terminals (also
known as mobile stations and/or user equipment units (UEs))
communicate via a radio access network (RAN) to one or more core
networks. The radio access network (RAN) covers a geographical area
which is divided into cell areas, with each cell area being served
by a base station, e.g., a radio base station (RBS), which in some
networks may also be called, for example, a "NodeB" (UMTS) or
"eNodeB" (LTE). A cell is a geographical area where radio coverage
is provided by the radio base station equipment at a base station
site. Each cell is identified by an identity within the local radio
area, which is broadcast in the cell. The base stations communicate
over the air interface operating on radio frequencies with the user
equipment units (UE) within range of the base stations.
[0005] In some versions of the radio access network, several base
stations are typically connected (e.g., by landlines or microwave)
to a controller node (such as a radio network controller (RNC) or a
base station controller (BSC)) which supervises and coordinates
various activities of the plural base stations connected thereto.
The radio network controllers are typically connected to one or
more core networks.
[0006] The Universal Mobile Telecommunications System (UMTS) is a
third generation mobile communication system, which evolved from
the second generation (2G) Global System for Mobile Communications
(GSM). UTRAN is essentially a radio access network using wideband
code division multiple access for user equipment units (UEs). In a
forum known as the Third Generation Partnership Project (3GPP),
telecommunications suppliers propose and agree upon standards for
third generation networks and UTRAN specifically, and investigate
enhanced data rate and radio capacity. Specifications for the
Evolved Universal Terrestrial Radio Access Network (E-UTRAN) are
ongoing within the 3.sup.rd Generation Partnership Project (3GPP).
The Evolved Universal Terrestrial Radio Access Network (E-UTRAN)
comprises the Long Term Evolution (LTE) and System Architecture
Evolution (SAE). Long Term Evolution (LTE) is a variant of a 3GPP
radio access technology wherein the radio base station nodes are
connected to a core network (via Serving Gateways, or SGWs) rather
than to radio network controller (RNC) nodes. In general, in LTE
the functions of a radio network controller (RNC) node are
distributed between the radio base stations nodes (eNodeB's in LTE)
and SGWs. As such, the radio access network (RAN) of an LTE system
has an essentially "flat" architecture comprising radio base
station nodes without reporting to radio network controller (RNC)
nodes.
[0007] Cellular Circuit-Switched (CS) telephony was introduced in
the first generation of mobile networks. Since then CS telephony
has become the largest service in the world with approximately 4
billion subscriptions sold. Even today, the main part of the mobile
operator's revenue comes from the CS telephony service (including
Short Message Services (SMS)), and the 2G GSM networks still
dominate the world in terms of subscriptions. 3G subscriptions are
increasing in volume, but that increase is less in part because of
users with handheld mobile terminals migrating from 2G to 3G and
more as a result of mobile broadband implemented via dongles or
embedded chipsets in laptops.
[0008] The long-term evolution (LTE) project within 3GPP aims to
further improve the 3G standard to, among other things, provide
even better mobile broadband to the end-users (higher throughput,
lower round-trip-times, etc.).
[0009] A common view in the telecommunication industry is that the
future networks will be all-IP networks. Based on this assumption,
the CS domain in was removed in the LTE work. As a result, the
telephony service cannot be used by a 3GPP Release 8 compliant LTE
terminal, unless one of the following four things is done:
(1) Implement CS fallback, (CSFB), so that an LTE terminal falls
back to 2G GSM when telephony service is used. (2) Implement 3GPP
Internet Protocol (IP) Multimedia Subsystem (IMS)/Multimedia
Telephony (MMTel), which is a simulated CS telephony service
provided over IP and IMS that inter-works with the Public Switched
Telephone Network (PSTN)/Public Land Mobile Network (PLMN). (3)
Implement a tunneling solution with Unlicensed Mobile Access
(UMA)/Generic Access Network (GAN) over LTE where the CS service is
encapsulated into an IP tunnel. (4) Implement a proprietary Voice
over IP (VoIP) solution with PSTN/PLMN interworking.
[0010] All of these four possibilities have drawbacks. In deployed
GSM networks that do not have Dual Transfer Mode (DTM)
capabilities; CS and Packet Switched (PS) services cannot be used
in parallel. Hence, all PS services running prior to a call to or
from a terminal using Circuit Switched Fallback (CSFB) are put on
hold or are terminated. If the GSM network has DTM, the PS
performance will be greatly reduced (from 10's of Mbps to 10's to
100's of kbps). One drawback with the CS fallback approach is that
when calling or being called and the terminal is falling back to
GSM and the CS service from LTE. Circuit Switched Fallback (CSFB)
also prolongs call set-up time.
[0011] The IMS/MMTel approach uses a completely new core/service
layer that is IMS based. This provides new possibilities to enhance
the service but also comes with the drawback of a financial hurdle
for the operator to overcome. A new core network drives capital
expenditures (CAPEX), and integration of that core network drives
an initial operating expenditures (OPEX) increase. Further, the
IMS/MMTel approach needs features implemented in the terminals and
the legacy CS network in order to handle voice handover to/from the
2G/3G CS telephony service.
[0012] Using UMA/GAN over LTE is not a standardized solution so a
drawback is that it is a proprietary solution which may make
terminal availability a problem. It also adds additional functions
to the core/service layer in both the network and terminal, e.g., a
GAN controller in the network and GAN protocols in the UE
terminal.
[0013] The proprietary VoIP approach, if operator controlled, comes
with the same drawbacks as for the IMS/MMTel (new core/service
layer) approach along with the difficulties associated with it
being proprietary and handover to 2G/3G CS may not be
supported.
[0014] There is yet a further solution for using a legacy CS
telephony service with a wireless terminal such as a 3GPP release
8-compliant LTE terminal. In that further solution, also known as a
type of Access Division Multiplexing (ADM), transmissions of GSM CS
voice are interleaved in between LTE transmissions. See, e.g.,
PCT/SE2007/000358, which is incorporated herein by reference. In
one example implementation of such an ADM solution a wireless
terminal simultaneously communicates with two TDMA-based radio
systems, e.g., the wireless terminal can maintain communications
paths to both systems by means of alternating in time its
communication between the two systems. The toggling between the two
systems is on a time scale small enough to effectively yield a
simultaneous communication between the two systems.
[0015] In an example ADM implementation such as that disclosed in
PCT/SE2007/000358, the first system can be a GSM system and the
second system can be an LTE system. The communication path to the
GSM system is used to maintain a radio channel for a CS voice
service; the LTE radio channel is used for data services.
[0016] In an example interleaved ADM solution shown in
PCT/SE2007/000358 the mobile station (wireless terminal) is capable
of transmission and reception of at most one radio system at any
one time (single receiver and single transmitter technology). In a
slightly different embodiment and mode the mobile station is
capable of maintaining two receiving radio channels in parallel
while still only capable of transmitting on one radio channel (dual
receiver and single transmitter technology). The dual receiver and
single transmitter implementation improves the performance by
simultaneous reception of data from the two systems while still
using interleaving (e.g., of PCT/SE2007/000358) for its uplink
transmission. The dual receiver single transmitter solution has a
higher cost of the mobile station since it requires double receiver
radio chains of radio parts.
SUMMARY
[0017] In one of its aspects the technology disclosed herein
provides mechanism(s) for transferring relevant radio-link related
information from type of network to another type of network (and
vice versa) by means of a wireless terminal (e.g., mobile station)
acting as a mediator for the corresponding measurement messages. In
an example preferred implementation the radio resource control
function is placed in a first network A (e.g., a GSM network). The
radio resource control function could equally well be placed in a
second network B (e.g., a LTE network), or any other radio network
constituting one of the networks A or B described herein.
[0018] In one of its aspects the technology disclosed herein
concerns a method of operating a communications system. The
communications system comprises a first radio access technology
network and a second radio access technology network. In an example
mode the method comprises a base station node of the second radio
access technology network performing a quality determination with
respect to an uplink transmission from a wireless terminal. The
base station node of the second radio access technology network
includes an indication of the quality determination with respect to
the uplink transmission from the wireless terminal in a link report
message transmitted to the wireless terminal. The wireless terminal
includes the indication of the quality determination with respect
to the uplink transmission from the wireless terminal based on the
indication received in the link report message in a proxy link
report message and transmits the proxy link report message to a
node of the first radio access technology network. A control node
of the first radio access technology network uses the quality
determination with respect to the uplink transmission from the
wireless terminal (as included in the proxy link report message) to
determine whether to perform a radio access technology handover
procedure.
[0019] In an example mode and embodiment, the wireless terminal
includes essentially the entire link report message (including the
indication of the quality determination with respect to the uplink
transmission from the wireless terminal) in a proxy link report
message and transmits the proxy link report message to a node of
the first radio access technology network. In another example mode
and embodiment, the wireless terminal obtains the indication of the
quality determination with respect to the uplink transmission and
inserts or otherwise includes the quality determination in the
proxy link report message. In yet another example mode and
embodiment, the wireless terminal obtains the indication of the
quality determination with respect to the uplink transmission and
processes or operates upon (e.g., filters or averages) the
indication of the quality determination and then inserts or
otherwise includes (as the indication of the quality determination)
a processed or derived indication of the quality determination in
the proxy link report message.
[0020] In an example mode and embodiment the method further
comprises the wireless terminal also providing, to the node of the
first radio access technology network, an indication of a quality
determination regarding a transmission between the wireless
terminal and the first radio access technology network. The node of
the first radio access technology network also uses the indication
of the signal quality between the wireless terminal and the first
radio access technology network to determine whether to perform the
radio access technology handover procedure. In an example
implementation, the wireless terminal also includes, in the proxy
link report message, the indication of the quality determination
regarding a transmission between the wireless terminal and the
first radio access technology network. In another example mode and
embodiment, the method further comprises the wireless terminal
including the indication of the quality determination regarding the
transmission between the wireless terminal and the first radio
access technology network in a wireless terminal separate link
report message.
[0021] In an example mode and embodiment the method further
comprises the wireless terminal making a determination regarding
signal quality of a third radio access technology network. The node
of the first radio access technology network also uses the
indication of the signal quality of the third radio access
technology network to determine whether to perform the radio access
technology handover procedure. In an example implementation the
wireless terminal includes the indication of the signal quality of
the third radio access technology network in the proxy link report
message. In another example implementation the wireless terminal
includes the indication of the signal quality of the third radio
access technology network in a wireless terminal separate link
report message.
[0022] In another of its aspects the technology disclosed herein
concerns a wireless terminal which serves as a multi-network
measurement communicator. The wireless terminal comprises a
communications interface and a link report processor. The
communications interface is configured to enable the wireless
terminal to communicate with a first radio access technology
network and a second radio access technology. The link report
processor is configured to receive a link report message from the
second radio access technology network and to prepare a proxy link
report message for transmission to a node of the first radio access
technology network. The link report message comprises an indication
of an uplink quality from the wireless terminal to the second radio
access technology network. The link report processor is configured
to include an indication of the quality determination in the proxy
link report message.
[0023] In an example embodiment, the communications interface is
configured to perform interleaved communications with the first
radio access technology network and the second radio access
technology network. In an example implementation the first radio
access technology network and the second radio access technology
network comprise a GSM network and a Long Term Evolution (LTE)
network.
[0024] In an example embodiment the wireless terminal further
comprises a wireless terminal measurement unit. The wireless
terminal measurement unit is configured to perform a downlink
quality measurement with respect to the first radio access
technology network and a downlink quality measurement with respect
to the second radio access technology network. The link report
processor and the communications interface are configured to
transmit an indication of at least one of the downlink quality
measurements to the node of the first radio access technology
network.
[0025] In an example embodiment the link report processor is
configured to include the indication of at least one of the
downlink quality measurements in the proxy link report message
which is sent to the node of the first radio access technology
network.
[0026] In another example embodiment the link report processor is
configured to include the indication of at least one of the
downlink quality measurements in a wireless terminal separate link
report message which is sent to the node of the first radio access
technology network separately from the proxy link report
message.
[0027] In an example embodiment the measurement unit is further
configured to make a signal quality determination for a third radio
access technology network. The link report processor and the
communications interface are configured to transmit an indication
of the signal quality of the third radio access technology network
to the node of the first radio access technology network. In an
example implementation, the link report processor is configured to
include the indication of the signal quality of the third radio
access technology network in the proxy link report message.
[0028] In another of its aspects the technology disclosed herein
concerns a method of operating a wireless terminal capable of
communicating with a first radio access technology network and a
second radio access technology. The wireless terminal method
comprises the wireless terminal receiving a link report message
from the second radio access technology network. The link report
message comprises an indication of an uplink quality from the
wireless terminal to the second radio access technology network.
The wireless terminal method further comprises the wireless
terminal including an indication of the quality determination in a
proxy link report message and transmitting the proxy link report
message to a node of the first radio access technology network.
[0029] In an example mode and embodiment the wireless terminal
method further comprises the wireless terminal performing
interleaved communications with the first radio access technology
network and the second radio access technology network. In an
example implementation the first radio access technology network
and the second radio access technology network comprise a GSM
network and a Long Term Evolution (LTE) network.
[0030] In an example mode and embodiment the wireless terminal
method further comprises the wireless terminal making a downlink
quality determination with respect to the first radio access
technology network and a downlink quality determination with
respect to the second radio access technology network, and the
wireless terminal transmitting an indication of at least one of the
downlink quality determinations to the node of the first radio
access technology network. In an example implementation the
wireless terminal method further comprises the wireless terminal
including the indication of the at least one of the downlink
quality determinations in the proxy link report message. In another
example implementation, the wireless terminal method further
comprises the wireless terminal including the indication of the at
least one of the downlink quality determinations in a wireless
terminal separate link report message which is sent to the node of
the first radio access technology network separately from the proxy
link report message.
[0031] In an example mode and embodiment the wireless terminal
method further comprises the wireless terminal making a
determination of downlink quality with respect to a third radio
access technology network and the wireless terminal transmitting an
indication of the signal quality of the third radio access
technology network to the node of the first radio access technology
network. In an example implementation the wireless terminal method
further comprises the wireless terminal including the indication of
the signal quality of the third radio access technology network in
the proxy link report message.
[0032] In another of its aspects the technology disclosed herein
concerns a radio base station node. The radio base station node
comprises a communications interface; a base station measurement
unit; and a base station link report processor. The communications
interface is configured to handle uplink and downlink transmissions
with respect to a wireless terminal. The base station measurement
unit is configured to perform a quality measurement with respect to
the uplink transmissions from the wireless terminal. The base
station link report processor is configured to include an
indication of the quality measurement in a downlink message to the
wireless terminal.
[0033] In another of its aspects the technology disclosed herein
concerns a radio access network handover control node. The radio
access network handover control node comprises a control node link
report processor and a handover unit. The control node link report
processor is configured to receive a link report message and a
proxy link report message. The handover unit is configured to use
both the link report message and the proxy link report message to
determine whether to perform handover from the first radio access
technology network to the second radio access technology network.
The link report message includes an indication of a quality
measurement regarding a transmission between a wireless terminal
and a node of the first network. The handover unit is configured to
receive the proxy link report message from the wireless terminal
through the first radio access technology network, the proxy link
report including an indication of a quality determination regarding
an uplink transmission from the wireless terminal to a node of the
second radio access technology network.
BRIEF DESCRIPTION OF THE DRAWINGS
[0034] The foregoing and other objects, features, and advantages of
the invention will be apparent from the following more particular
description of preferred embodiments as illustrated in the
accompanying drawings in which reference characters refer to the
same parts throughout the various views. The drawings are not
necessarily to scale, emphasis instead being placed upon
illustrating the principles of the invention.
[0035] FIG. 1 is a diagrammatic view of a system in which a
wireless terminal (e.g., mobile station) is simultaneously active
in a radio communication with two radio networks A and B while also
being in the coverage area of a third network C.
[0036] FIG. 2 is a schematic view of a communications system
comprising two radio access technology networks and a wireless
terminal which serves as a multi-network measurement
communicator.
[0037] FIG. 3 is a schematic view of a communications network
comprising three radio access technology networks and a wireless
terminal which serves as a multi-network measurement
communicator.
[0038] FIG. 4A is a diagrammatic view of an example embodiment of a
multi-network measurement communicating wireless terminal.
[0039] FIG. 4B is a diagrammatic view of another example embodiment
of a multi-network measurement communicating wireless terminal, and
particularly an example embodiment of a multi-network measurement
communicating wireless terminal which processes or operates upon
(e.g., filters or averages) an indication of the quality
determination and then inserts or otherwise includes (as the
indication of the quality determination) a processed or derived
indication of the quality determination in the proxy link report
message.
[0040] FIG. 5 is a more detailed diagrammatic view of an example
embodiment of a multi-network measurement communicating wireless
terminal.
[0041] FIG. 6 is a yet more detailed diagrammatic view of an
example embodiment of a multi-network measurement communicating
wireless terminal.
[0042] FIG. 7 is a diagrammatic view of an example embodiment of a
base station node configured to prepare a link report message for
transmission to a multi-network measurement wireless terminal.
[0043] FIG. 8 is a more detailed diagrammatic view of an example
embodiment of a base station node configured to prepare a link
report message for transmission to a multi-network measurement
wireless terminal.
[0044] FIG. 9 is a diagrammatic view of an example embodiment of a
base station control node.
[0045] FIG. 10 is a more detailed diagrammatic view of an example
embodiment of a base station control node.
[0046] FIG. 11 is a flowchart showing example, representative acts
or steps comprising a basic method of operating a wireless terminal
as a multi-network measurement communicator.
[0047] FIG. 11A is a flowchart showing example, representative acts
or steps comprising another method of operating a wireless terminal
as a multi-network measurement communicator.
[0048] FIG. 11B is a flowchart showing example, representative acts
or steps comprising yet another method of operating a wireless
terminal as a multi-network measurement communicator.
[0049] FIG. 12 is a flowchart showing the basic method of FIG. 11
wherein the wireless terminal is suitable for performing
multiplexing or interleaving with respect to plural radio access
technology networks.
[0050] FIG. 13 is a diagrammatic view showing the basic method of
FIG. 11 as augmented by the wireless terminal making one or more
downlink quality measurements and including an indication of at
least one of the downlink quality measurements in a proxy link
report message.
[0051] FIG. 14 is a diagrammatic view showing the basic method of
FIG. 11 as augmented by the wireless terminal making one or more
downlink quality measurements and including an indication of at
least one of the downlink quality measurements in a separate link
report message which precedes the proxy link report message.
[0052] FIG. 15 is a diagrammatic view showing the basic method of
FIG. 11 as augmented by the wireless terminal making one or more
downlink quality measurements and including an indication of at
least one of the downlink quality measurements in a separate link
report message which is subsequent to the proxy link report
message.
[0053] FIG. 16 is a diagrammatic view showing the basic method of
FIG. 13 as augmented by the wireless terminal making and reporting
measurements with respect to yet another network and including the
measurements with respect to the yet other network in a proxy link
report message.
[0054] FIG. 17 is a diagrammatic view showing the basic method of
FIG. 13 as augmented by the wireless terminal making and reporting
measurements with respect to yet another network and including the
measurements with respect to the yet other network in a separate
link report message which precedes the proxy link report
message.
[0055] FIG. 18 is a diagrammatic view showing the basic method of
FIG. 13 as augmented by the wireless terminal making and reporting
measurements with respect to yet another network and including the
measurements with respect to the yet other network in a separate
link report message which is subsequent to the proxy link report
message.
[0056] FIG. 19 is a flowchart showing example, representative acts
or steps comprising a basic method of operating a communication
system which includes a multi-network measurement capability.
[0057] FIG. 20 is a diagrammatic view showing the basic method of
FIG. 19 as augmented by the wireless terminal making one or more
downlink quality measurements and including an indication of at
least one of the downlink quality measurements in a proxy link
report message.
[0058] FIG. 21 is a diagrammatic view showing the basic method of
FIG. 19 as augmented by the wireless terminal making one or more
downlink quality measurements and including an indication of at
least one of the downlink quality measurements in a separate link
report message which precedes the proxy link report message.
[0059] FIG. 22 is a diagrammatic view showing the basic method of
FIG. 19 as augmented by the wireless terminal making and reporting
measurements with respect to yet another network and including the
measurements in the proxy link report message.
[0060] FIG. 23 is a diagrammatic view showing the basic method of
FIG. 19 as augmented by the wireless terminal making and reporting
measurements with respect to yet another network and including the
measurements with respect to the yet other network in a separate
link report message which is subsequent to the proxy link report
message.
DETAILED DESCRIPTION
[0061] In the following description, for purposes of explanation
and not limitation, specific details are set forth such as
particular architectures, interfaces, techniques, etc. in order to
provide a thorough understanding of the present invention. However,
it will be apparent to those skilled in the art that the present
invention may be practiced in other embodiments that depart from
these specific details. That is, those skilled in the art will be
able to devise various arrangements which, although not explicitly
described or shown herein, embody the principles of the invention
and are included within its spirit and scope. In some instances,
detailed descriptions of well-known devices, circuits, and methods
are omitted so as not to obscure the description of the present
invention with unnecessary detail. All statements herein reciting
principles, aspects, and embodiments of the invention, as well as
specific examples thereof, are intended to encompass both
structural and functional equivalents thereof. Additionally, it is
intended that such equivalents include both currently known
equivalents as well as equivalents developed in the future, i.e.,
any elements developed that perform the same function, regardless
of structure.
[0062] Thus, for example, it will be appreciated by those skilled
in the art that block diagrams herein can represent conceptual
views of illustrative circuitry or other functional units embodying
the principles of the technology. Similarly, it will be appreciated
that any flow charts, state transition diagrams, pseudocode, and
the like represent various processes which may be substantially
represented in computer readable medium and so executed by a
computer or processor, whether or not such computer or processor is
explicitly shown.
[0063] The functions of the various elements including functional
blocks, including but not limited to those labeled or described as
"computer", "processor" or "controller", may be provided through
the use of hardware such as circuit hardware and/or hardware
capable of executing software in the form of coded instructions
stored on computer readable medium. Thus, such functions and
illustrated functional blocks are to be understood as being either
hardware-implemented and/or computer-implemented, and thus
machine-implemented.
[0064] In terms of hardware implementation, the functional blocks
may include or encompass, without limitation, digital signal
processor (DSP) hardware, reduced instruction set processor,
hardware (e.g., digital or analog) circuitry including but not
limited to application specific integrated circuit(s) [ASIC], and
(where appropriate) state machines capable of performing such
functions.
[0065] In terms of computer implementation, a computer is generally
understood to comprise one or more processors or one or more
controllers, and the terms computer and processor and controller
may be employed interchangeably herein. When provided by a computer
or processor or controller, the functions may be provided by a
single dedicated computer or processor or controller, by a single
shared computer or processor or controller, or by a plurality of
individual computers or processors or controllers, some of which
may be shared or distributed. Moreover, use of the term "processor"
or "controller" shall also be construed to refer to other hardware
capable of performing such functions and/or executing software,
such as the example hardware recited above.
[0066] There are still network functions yet to be solved for the
above-described radio behavior and transmitter/receiver
implementations of the transmitter and receiver technology for an
Access Division Multiplexing system such as disclosed in
PCT/SE2007/000358, for example. Among the network functions yet to
be solved are those related to paging, registration, handoff, and
mobility that are required by a mobile that is simultaneously
engaged in a circuit switched (CS) voice service in one network and
a packet data service in a second network.
[0067] The technology disclosed herein concerns, e.g., the problem
of having a network-controlled handoff (e.g., a network-controlled
handoff algorithm) in a situation where a mobile station is
simultaneously connected to two different radio networks.
[0068] In cellular radio systems such as Global System for Mobile
communication (GSM), Wideband Code Division Multiple Access
(WCDMA), cdma1x, Evolution Data Optimized (EVDO), Long Term
Evolution (LTE) and others the network is responsible for
evaluating different cell alternatives for a mobile station in
active mode. As used herein, "active mode" means that that the
mobile station is actively engaged in a data transfer, a voice
call, or both. In GSM this is equivalent to the mobile station
being in dedicated mode while in WCDMA and LTE the wireless
terminal (e.g., mobile station) has an established radio bearer and
radio resource context respectively. In each of the systems noted
above, when the mobile station is active in its communication, the
network does radio-link quality measurements on the uplink
transmissions from the mobile station to the radio-base station.
Similarly the mobile station does quality measurement on the
downlink radio transmission. The measurements in both the uplink
and the downlink can contain combinations of signal strength
measurements, bit-error measurements, estimated bit-error
probabilities, frame erasure rates, block error rates or any other
relevant indicators for the quality of the radio link. The
measurements in the downlink are specified, e.g., by the 3GPP
Technical Specifications. The mobile station also performs quality
measurements on candidate non-serving radio cells in addition to
the quality measurements on the active radio channels. These
quality measurements typically involve measuring signal strengths
only, but can also contain other measures either directly or
indirectly.
[0069] In order for the network to evaluate the serving and
neighboring cells with respect to radio performance for a mobile
station, a network radio resource control entity which performs the
evaluation needs quality information (e.g., measurements) both from
the network itself (relating to the uplink radio quality) and from
the mobile station (relating to the downlink radio quality and the
quality of radio links to neighboring cells). In state of the art
technology this is done by instructing the mobile station to send
its measurements (or a representation of its measurements) to the
network in a set of well defined link reports. The link reports are
either sent continuously as in GSM and WCDMA or conditionally
relative a set of radio and traffic conditions as in LTE. A
resource management control unit in the network then combines the
quality information in the link reports sent by the mobile station
with network maintained information from the network measurements.
The combined information about uplink-, downlink- and neighboring
cell radio-link quality is used by the network in a set of locating
algorithms to determine the best cell for the mobile to be
connected. The locating algorithms are typically not standardized
but may differ from system to system. In the preferred
implementation the network then uses the results from the locating
algorithm to determine whether the serving cell is the preferred
cell (in which case no handoff command is sent to the mobile
station) or if one of the neighboring cells is preferred (in which
case a handoff is prepared and an appropriate handoff command is
sent to the mobile station).
[0070] The technology disclosed herein addresses, e.g., a problem
illustrated in the context of FIG. 1. FIG. 1 shows a communication
system 20 comprising three networks 22, e.g., network 22A, network
22B, and network 22C. Although unillustrated in FIG. 1, some
networks 22 comprise base station control nodes 26 (e.g., base
station controller nodes or radio network controller nodes). Each
network 22 has one or more base stations 28, such base station 28A
for network 22A, base station 28B for network 22B, and base station
28C for network 22C.
[0071] In the situation shown in FIG. 1, mobile station or wireless
terminal 30 is simultaneously active in a radio communication with
two radio networks, e.g., network 22A and network 22B. In an
example situation, network 22A can be, e.g., a GSM radio network
and network 22B can be a LTE radio network. In the FIG. 1
situation, a radio resource control unit (located, e.g., at base
station control node 26) would need measurement information from
the mobile station, the network 22 A, and the network 22B.
[0072] Thus, in an example situation shown in FIG. 1 wireless
terminal 30 is actively communicating in a GSM network
(system/network 22A) and actively communicating in an LTE network
(system/network 22B) while also being in the coverage area of a
WCDMA network (system/network 22C). The quality (e.g., measurement)
information from the wireless terminal 30 is needed to evaluate the
downlink performance of the radio communication with network 22A
and with network 22B. The quality information from the wireless
terminal 30 is further needed by the radio resource control
function to evaluate the expected radio performance should the
mobile station be handed off to a neighboring cell in network 22C.
The quality information from network 22A is needed to evaluate the
quality of the uplink radio communication with network 22A and
potentially also other relevant information kept by network 22A
such as load situation and network level interference levels.
Similarly quality information from network 22B is needed to
evaluate the quality of the uplink radio communication with network
22B and potentially also other relevant information kept by network
22B such as load situation and network level interference levels.
Any effective radio resource control function would need all the
information above to be able to evaluate the total radio-link
performance (communication with both system 22A and system 22B) and
compare with the estimated performance after a potential handoff to
system 22C.
[0073] A problem is that with present state of the art the radio
resource control function cannot have the desired quality
information from wireless terminal 30, network 22A, and network
22B. This is because there is no mechanism available to transfer
the quality information from network 22A to network 22B, or vice
versa. This means that if the radio resource control function is
placed in network 22A (e.g., in the GSM network), with present
state of the art technology the radio resource control function
would not have any information relating to uplink performance of
the communication with network 22B (e.g., the LTE network) or
indeed any other relevant information kept by network 22B such as
load situation. Similarly, if the radio resource control function
were placed in network 22B (e.g., the LTE network), with present
state of the art technology the radio resource control function
would not have any information relating to uplink performance of
the communication with network 22A (e.g., GSM network) or indeed
any other relevant information kept by network 22A such as load
situation.
[0074] The problem implies severe restrictions to the performance
of the communication service in a multi-radio technology network
scenario such as depicted in FIG. 1. As one example, if the radio
resource control unit is placed in the system 22B (e.g., the LTE
system) the radio resource control function would be ignorant about
the uplink GSM voice performance (GSM here being the network 22A).
If the mobile station finds itself in a location with high enough
uplink (UL) path loss, e.g., deep inside a building, the GSM voice
call would be dropped by the GSM network without the radio resource
control function even being aware of the poor quality in the GSM
uplink communication. But had the radio resource control function
had the relevant quality information from network 22A, the dropped
call could have been prevented by a handoff to network 22C before
the uplink radio link in network 22A was lost.
[0075] In one of its aspects the technology disclosed herein
provides mechanism(s) for transferring relevant radio-link related
information from one network to another network, e.g., from network
22B to network 22A (and vice versa) by means of a wireless terminal
30 (e.g., mobile station) acting as a mediator or relay or
multi-network communicator for the corresponding quality
messages.
[0076] In an example implementation (such as illustrated in FIG.
2), the radio resource control function is placed in network A
(e.g., the GSM network). However, it should be understood that the
radio resource control function could equally well be placed in
network B (e.g., the LTE network), or any other radio network
constituting one of the networks A or B or any other network
described herein.
[0077] In one example communications system 20(2) illustrated in
FIG. 2, the radio resource control function (RRCU) 34A is
implemented in the GSM base station controller (BSC) 26A as part of
network 22A. In this example scenario, network 22A comprises at
least one GSM base station (RBS 28A) connected to at least on base
station controller (BSC) 26A. The base station controller 26A
contains or comprises radio resource control function (RRCU) 34A
and memory unit (MU1) 36A.
[0078] Another example communications system 20(3), shown in FIG.
3, resembles that of FIG. 2 but further includes network 22C. The
network 22C comprises at least one radio base station (RBS) 28C
which is connected to at least one radio network controller (RNC)
26C. In the example of FIG. 3, the network 22C is a WCDMA radio
access technology network. It should be understood, however, that
network 22C is intended to be representative of a third network,
and need not be a WCDMA radio access technology network but could
be, for example, another GSM or LTE network, or even another of the
networks mentioned above.
[0079] As shown in FIG. 2 at least one wireless terminal 30 moves
in the coverage area of the radio base station 28A (of network 22A)
and the radio base station 28B (of network 22B). FIG. 3 shows the
wireless terminal (UE) 30 moving in the coverage area of the radio
base station 28A (of network 22A), the radio base station 28B (of
network 22B), and the radio base station 28C (of network 22C). The
wireless terminal 30 comprises memory unit (MU2) 38.
[0080] In the scenario depicted in FIG. 2, the network 22A performs
GSM uplink radio measurements of the uplink communication link to
network 22A in the RBS 28A according to 3GPP Technical
Specifications. Using known technology the measurement results are
transported from the RBS 28A over the Abis interface to the BSC 26A
which stores the measurement/link report in memory unit (MU1) 36A
accessible to the radio resource control unit (RRCU) 34A.
[0081] In parallel the LTE RBS 28B--being part of network
22B--performs quality measurement of the uplink radio radio-link
communication channel from the wireless terminal 30 to the Long
Term Evolution (LTE) RBS 28B. Using the technology disclosed
herein, the RBS 28B periodically writes the measurement results in
a link report message (MRM1) that is sent on the downlink radio
channel to the wireless terminal 30. Alternatively the link report
can comprise processed measurement results such as the filtered
signal strength or average values of the performance indications
measured by the Long Term Evolution (LTE) radio base station RBS
28B. As used herein a "link report" can include any information
germane to a handover decision, and thus includes but is not
limited to link-related information such as measurements such as
those just mentioned.
[0082] The wireless terminal 30 receives the link report message
MRM1 and stores the information therein in local memory unit (MU2)
38 implemented in wireless terminal 30. In parallel to this process
the wireless terminal 30 uses prior art technology to measure the
performance quality of the downlink communication channels relating
to network 22A and network 22B respectively. In the FIG. 3
embodiment, wireless terminal 30 also uses known technology to
measure the signal strength and/or acquire other quality
information (e.g., measurement) relating to the expected radio
channel quality the wireless terminal 30 would get were it to
connect to any neighboring cell belonging to the network 22C
(network 22C being a WCDMA network in the FIG. 3 example
implementation).
[0083] Using the technology disclosed herein wireless terminal 30
subsequently constructs a link report message MRM2. In the link
report message MRM2 the wireless terminal 30 writes the information
stored in the memory unit MU2 that was received in the link report
message MRM1 previously received from the LTE RBS 28B. The wireless
terminal 30 optionally further writes into the link report message
MRM2 the quality (e.g., measurement) results obtained by the mobile
station on the downlink radio channels and on neighboring cells.
Further using the technology disclosed herein the wireless terminal
30 sends the link report message MRM2 to the radio resource control
function 34A in network 22A. The link report message MRM2 can be
sent over the radio link to the GSM RBS 28A which in turn forwards
this message across the Abis interface to the GSM BSC 26A where the
radio resource function 34A is implemented.
[0084] In a further act the BSC 26A stores the link report in the
memory unit (MU1) 36A accessible to the radio resource control unit
34A. The radio resource control unit 34A then has essentially all
necessary information available in the memory unit MU1 36A located
in the GSM BSC 26A.
[0085] It should be understood to the person skilled in the art
that there exist alternative implementations that differ in design
to the preferred example embodiment described above but which still
use the acts described herein. In one alternative embodiment the
roles of the networks 22A and 22B are reversed so that the radio
resource control unit resides in network 22B. In this modification
the roles of networks 22A and 22B are reversed and the link report
message is created in network 22A and sent to the mobile station
for further transmission to the network 22B. In yet an alternative
implementation the information contained in the link report message
MRM1 is sent in a first message from the wireless terminal to the
network 22A while the mobile station messages are sent in a second
message from the wireless terminal to network 22A. In still other
implementations the content of either of the link report messages
MRM1 and MRM2 comprise other sets of quality measurements, load
measurements, or any other information kept by either network 22B
or the mobile station that can be of relevance to the radio
resource control function in network 22A.
[0086] FIG. 4A illustrates in more detail an example embodiment of
a wireless terminal 30(A) which serves as a multi-network
relay/communicator. The wireless terminal 30(A) comprises
communications interface 40 and link report processor 42. The
communications interface 40 is configured to enable the wireless
terminal 30(A) to communicate over a radio interface with a first
radio access technology network (e.g., network 22A) and a second
radio access technology (e.g., network 22B). The link report
processor 42 is configured to receive a second network link report
message MRM1 from the second radio access technology network (e.g.,
22B) and to prepare a proxy link report message MRM2 for
transmission to a node of the first radio access technology network
22A (e.g., the base station control node 26A).
[0087] As understood from the foregoing, the link report message
MRM1 comprises an indication of an uplink quality measurement from
the wireless terminal 30 to the second radio access technology
network 22B (e.g., to base station 28B). The link report processor
42 of wireless terminal 30 is configured to include an indication
of the quality determination MRM1 in the proxy link report MRM2 for
transmission to the node (e.g., base station control node 26A) of
the first radio access technology network 22A.
[0088] In some example modes and embodiments, the wireless terminal
includes essentially the entire link report message (including the
indication of the quality determination with respect to the uplink
transmission from the wireless terminal) in the proxy link report
message MRM2 and transmits the proxy link report message MRM2 to
the node of (e.g., base station control node 26A) the first radio
access technology network.
[0089] In other example modes and embodiments, the wireless
terminal obtains the indication of the quality determination with
respect to the uplink transmission and inserts or otherwise
includes the quality determination (but not necessarily the entire
link report message) in the proxy link report message MRM2 before
transmitting the proxy link report message MRM2 to the node of the
first radio access technology network.
[0090] In yet other example modes and embodiments represented by
FIG. 4, the wireless terminal obtains the indication of the quality
determination with respect to the uplink transmission and processes
or operates upon (e.g., filters or averages) the indication of the
quality determination and then inserts or otherwise includes (as
the indication of the quality determination) a processed or derived
indication of the quality determination in the proxy link report
message.
[0091] In any of the example modes and embodiments described
herein, the wireless terminal may obtain the indication of the
quality determination with respect to the uplink transmission; then
process or operates upon the information received in a link report
message (e.g., the indication of the quality determination); and
then include a result or output of such processed or operated-upon
information in the proxy link report message as the "quality
determination". The processing or operating upon the information
received in a link report message may involve or include the
information received in a link report message from any network,
including the second radio access technology network (received in
e.g., the link report message MRM1) and the third radio access
technology network (received in, e.g., the link report message
MRM3). The result or output of any such processed or operated-upon
information is still considered an "indication" of the quality
determination of the uplink quality for the particular link for
which quality is assessed. It should therefore be understood that,
with reference to any embodiment or mode described herein, usage of
the "indication" or "quality indication" may be an output or result
of a processing or operation upon the indication of quality
determination as received in the link report message, and is indeed
based upon the link report message.
[0092] The operation or processing performed on or with respect to
the information received in a link report message may be performed
by the link report processor 42 of any of the preceding embodiments
or other embodiments encompassed hereby. In one example
implementation illustrated in FIG. 4B, such operation or processing
may include filtering or averaging. For example, FIG. 4B shows a
filter F which performs simple filtering such as maintaining a
running average, with the filtered or averaged result being
reporting as the indication of the quality determination (rather
than the raw data which was actually included in the link report
message and upon which the filtered or averaged result or output is
based).
[0093] In an example embodiment, the communications interface 40 is
configured to perform interleaved communications with the first
radio access technology network 22A and the second radio access
technology network 22B in accordance with techniques such as, for
example, those disclosed in PCT/SE2007/000358. In a non-limiting
example implementation the first radio access technology network
22A and the second radio access technology network 22B comprise a
GSM network and a Long Term Evolution (LTE) network,
respectively.
[0094] In the example embodiment of FIG. 4A the wireless terminal
30 further comprises wireless terminal measurement unit 44. The
wireless terminal measurement unit 44 is configured to perform a
downlink quality measurement with respect to the first radio access
technology network 22A and a downlink quality measurement with
respect to the second radio access technology network 22B. The link
report processor 42 and the communications interface 40 are
configured to transmit an indication of at least one of the
downlink quality measurements to the node of the first radio access
technology network (e.g., to base station control node 26A of
network 22A).
[0095] In an example embodiment the link report processor 42 is
configured to include the indication of at least one of the
downlink quality measurements in the proxy link report message MRM2
which is sent to the node 26A of the first radio access technology
network 22A. In another example embodiment the link report
processor 42 is configured to include the indication of at least
one of the downlink quality measurements in a wireless terminal
separate link report message MRM3 which is sent to the node 26A of
the first radio access technology network 22A separately from the
proxy link report message MRM2.
[0096] In an example embodiment such as that understood with
reference to FIG. 3, the measurement unit 44 is further configured
to measure signal quality of a cell of a third radio access
technology network 22C. The link report processor 42 and the
communications interface 40 are configured to transmit an
indication of the signal quality of a cell of the third radio
access technology network 22C to the node 26A of the first radio
access technology network 22C. In an example implementation, the
link report processor 42 is configured to include the indication of
the signal quality of a cell of the third radio access technology
network 22C in the proxy link report message MRM2.
[0097] FIG. 5 shows yet more details of an example wireless
terminal, such as wireless terminal 30(5). In addition to wireless
terminal elements and functionalities already discussed, wireless
terminal 30(5) comprises multi-radio access technology/network
scheduler 50 which schedules the interleaved or multiplexed
transmissions to/from plural networks, e.g., network 22A and
network 22B. FIG. 5 further shows that the link report processor 42
can comprise, in an example embodiment, analysis unit 52 and report
preparation unit 54. The analysis unit 52 serves to analyze the
link report message MRM1 received from the base station 28B. The
report preparation unit 54 serves to prepare the link report
message MRM2 (and optionally the wireless terminal separate link
report message MRM3) which is sent to base station control node
26A.
[0098] Broken line 60 depicts, in FIG. 5 as well as other figures,
a platform by which functionalities and units illustrated within
line 60 can be realized in example embodiments. The terminology
"platform" is a way of describing how the functional units of
wireless terminal 30 can be implemented or realized by machine. One
example platform is a computer implementation wherein one or more
of the elements framed by line 60, including link report processor
42 and wireless terminal measurement unit 44 are realized by one or
more processors which execute coded instructions stored in memory
(e.g., non-transitory signals) in order to perform the various acts
described herein. In such a computer implementation the wireless
terminal 30 can comprise, in addition to a processor(s), a memory
section 62 (which in turn can comprise random access memory 64;
read only memory 66; application memory 68 (which stores, e.g.,
coded instructions which can be executed by the processor to
perform acts described herein); and any other memory such as cache
memory, for example).
[0099] Whether or not specifically illustrated, typically the
wireless terminal 30 of each of the embodiments discussed herein
can also comprise certain input/output units or functionalities,
the representative input/output units for wireless terminal 30
being illustrated in FIG. 5 as keypad 70; audio input device (e.g.
microphone) 72; visual input device (e.g., camera) 74; visual
output device (e.g., display 76); and audio output device (e.g.,
speaker) 78. Other types of input/output devices can also be
connected to or comprise wireless terminal 30.
[0100] In the example of FIG. 5 and other drawings the platform
depicted by line 60 has been illustrated as computer-implemented or
computer-based platform. Another example platform for wireless
terminal 30 can be that of a hardware circuit, e.g., an application
specific integrated circuit (ASIC) wherein circuit elements are
structured and operated to perform the various acts described
herein.
[0101] FIG. 6 illustrates in more detail how wireless terminal
30(6) can comprise first controller 80A configured to handle
administration and transmissions of network 22A and second
controller 80B configured to handle administration and
transmissions of network 22B. First controller 80A and second
controller 80B can be realized or implemented by a same processor
or controller (or processor system), and in such case may
constitute separate sets of non-transitory executable signals
(e.g., programs or routines stored on tangible media). FIG. 6
specifically shows how various ones of the aforementioned units,
such as link report processor 42 and wireless terminal measurement
unit 44, can have separate subsections thereof (e.g., link report
processor 42A and link report processor 42B) associated with the
respective networks 22A and 22B.
[0102] As used herein, "wireless terminal(s)" or "UE" can be mobile
stations or user equipment units (UE) such as but not limited to
mobile telephones ("cellular" telephones) and laptops with wireless
capability), e.g., mobile termination), and thus can be, for
example, portable, pocket, hand-held, computer-included, or
car-mounted mobile devices which communicate voice and/or data with
radio access network.
[0103] FIG. 7 illustrates, in simplified manner, an example
embodiment of a radio base station node 28. The base station 28 of
FIG. 7 is intended to be a representative base station node for any
suitable radio access technology network and is configured to
prepare a link report message MRM1 for transmission to the wireless
terminal 30. To this end the radio base station node 28 comprises
communications interface 100; base station measurement unit 104;
and base station link report processor 106. The communications
interface 100 is configured to handle uplink and downlink
transmissions over a radio or air interface with respect to
wireless terminal 30. The base station measurement unit 104 is
configured to perform a quality measurement with respect to the
uplink transmissions from wireless terminal 30. The base station
link report processor 106 is configured to include an indication of
the quality measurement in a downlink message (e.g., MRM1 (e.g.,
link report message MRM1) to wireless terminal 30.
[0104] FIG. 8 shows an example embodiment radio base station node
28 in somewhat more detail. In addition to communications interface
100, base station measurement unit 104, and base station link
report processor 106, the base station 28 of FIG. 8 further
comprises interface 108 (an interface to core network(s));
scheduler 110; and memory 112 (including application(s) memory
118). FIG. 8 illustrates also base station measurement unit 104 as
comprising analysis unit 120 and report preparation unit 122.
[0105] In similar manner as illustrated elsewhere herein, in an
example embodiment the base station 28 comprises a platform simply
depicted as broken line 124. Units and functionalities shown within
platform line 124, including base station measurement unit 104 and
base station link report processor 106, are in this example
embodiment realized by machine implementation such as by computer
implementation and/or at least partially by hardware implementation
(e.g., a circuit or ASIC, for example). Comments herein concerning
computer and/or processor and/or controller implementation in
general thus also apply to base station 28, which can also have
numerous input and output units such as those previously described
for wireless terminal 30.
[0106] FIG. 9 shows an example embodiment of a base station control
node 26, also known herein as a radio access network handover
control node. As shown in FIG. 9, radio access network handover
control node 26 comprises control node link report processor 130
and handover unit 132. The control node link report processor 130
is configured to receive a home network quality link report (from a
home network to which base station control node 26 belongs) and a
foreign network quality link report (concerning a foreign network
to which base station control node 26 does not belong). The
handover unit 132 is configured to use both the home network
quality link report and the foreign network quality link report to
determine whether to perform a radio access technology handover to
the foreign network. The home network quality link report includes
an indication of a quality measurement regarding a transmission
between wireless terminal 30 and a node of the home network (e.g.,
base station node 28A for base station control node 26A). The
foreign network quality link report is included in a proxy link
report message (e.g., proxy link report message MRM2) received from
wireless terminal 30 through the home network. The foreign network
quality link report comprises handover-germane information such as,
for example, an indication of a quality measurement regarding an
uplink transmission from wireless terminal 30 to a node of the
foreign network (e.g., base station 28B of network 22B in FIG. 2,
for example).
[0107] FIG. 10 shows an example embodiment base station control
node 26 in a more specific implementation. In addition to control
node link report processor 130 and handover unit 132, FIG. 10
illustrates base station control node 26 as comprising interface
134 to home network base stations (such as base station 28A when
the base station control node is base station control node 26A);
interface 136 to a suitable core network; resource allocation and
traffic handling unit 138; and memory 142 (including application(s)
memory 148).
[0108] In similar manner as illustrated elsewhere herein, in an
example embodiment the base station control node 26 comprises a
platform simply depicted as broken line 150. Units and
functionalities shown within platform line 150, including handover
unit 132 and handover unit 134, are in this example embodiment
realized by machine implementation such as by computer
implementation and/or at least partially by hardware implementation
(e.g., a circuit or ASIC, for example). Comments herein concerning
computer and/or processor and/or controller implementation in
general thus also apply to base station control node 26, which can
also have numerous input and output units such as those previously
described for wireless terminal 30.
[0109] FIG. 11 illustrates example, representative acts or steps
comprising a basic method of operating a wireless terminal (such as
wireless terminal 30 of FIG. 2) capable of communication over a
radio interface with at least a first radio access technology
network (e.g., network 22A) and a second radio access technology
(e.g., network 22B). Act 11-1 comprises the wireless terminal
receiving a link report message (e.g., link report message MRM1)
from the second radio access technology network. The link report
message MRM1 comprises handover-germane link information as
assessed by the second network, e.g., an indication of an uplink
quality (e.g., an uplink quality measurement) from the wireless
terminal 30 to the second radio access technology network. The
uplink quality measurement from the wireless terminal 30 to the
second radio access technology network can be made by base station
measurement unit 104, and the link report message prepared by base
station link report processor 106 (see FIG. 8). Act 11-2 of the
wireless terminal method further comprises the wireless terminal
including the indication of an uplink quality in a proxy link
report message (e.g., proxy link report message MRM2) and
transmitting the proxy link report message to a node of the first
radio access technology network (e.g., to base station control node
26A of network 22A in the example embodiment of FIG. 2).
[0110] FIG. 11A shows an example mode and embodiment similar to
that of FIG. 11, but wherein as act 11A-2 the wireless terminal
includes essentially the entire link report message (including the
indication of the quality determination with respect to the uplink
transmission from the wireless terminal) in the proxy link report
message MRM2 and transmits the proxy link report message MRM2 to
the node of (e.g., base station control node 26A) the first radio
access technology network.
[0111] FIG. 11B shows another example mode and embodiment also
similar to that of FIG. 11 but further described with reference to
FIG. 24. In the mode and embodiment of FIG. 11B as act 11-1 the
wireless terminal receives or obtains the indication of the quality
determination with respect to the uplink transmission (e.g., in the
link report message). As act 11B-1 the wireless terminal processes
or operates upon (e.g., filters or averages) the indication of the
quality determination (as received in the link report message) to
obtain a processed or operated-upon output or result which is also
considered as an "indication of the quality determination". As act
11B-2 the wireless terminal inserts or otherwise includes (as the
indication of the quality determination) a processed or derived
indication of the quality determination in the proxy link report
message.
[0112] FIG. 12 resembles FIG. 11, but further illustrates the fact
that, in an example mode and embodiment, as act 11-3 the wireless
terminal method further comprises the wireless terminal performing
interleaved or multiplexed communications with the first radio
access technology network and the second radio access technology
network. In an example implementation the first radio access
technology network and the second radio access technology network
comprise a GSM network and a Long Term Evolution (LTE) network. The
interleaved or multiplexed communications can be in accordance with
the techniques described in PCT/SE2007/000358, for example, which
is incorporated herein by reference.
[0113] FIG. 13 illustrates that, in another example mode and
embodiment, the acts of FIG. 11 can be augmented with one or more
downlink quality determinations made by wireless terminal 30. Act
13-0 of FIG. 13 comprises the wireless terminal 30 performing a
downlink quality determination (e.g., measurement) with respect to
the first radio access technology network (e.g., network 22A of
FIG. 2) and a downlink quality determination with respect to the
second radio access technology network (e.g., network 22B of FIG.
2). In an example embodiment of FIG. 4A, for example, the downlink
quality determinations can be made by wireless terminal measurement
unit 44. As a further act 13-1, the wireless terminal transmits an
indication of at least one of the downlink quality determinations
to the node of the first radio access technology network (e.g., to
base station control node 26A of FIG. 2). In the particular
embodiment and mode shown in FIG. 13, the indication of at least
one of the downlink quality determinations is included in the proxy
link report message (e.g., proxy link report message MRM2) which is
sent to the node of the first radio access technology network. In
another example embodiment and mode shown in FIG. 14, as act 14-0
the wireless terminal includes the indication of at least one of
the downlink quality determinations in a wireless terminal separate
link report message (e.g., wireless terminal separate link report
message MRMS) which is sent to the node of the first radio access
technology network separately from the proxy link report message.
In the mode of FIG. 14 the wireless terminal separate link report
message MRMS precedes the proxy link report message MRM2, but as
illustrated in FIG. 15 the wireless terminal separate link report
message MRMS can (as act 15-2) succeed (follow in time) the proxy
link report message MRM2 (act 15-1).
[0114] FIG. 16 shows the method of FIG. 13 being augmented by the
wireless terminal 30 making or obtaining determinations with
respect to quality of yet another network (e.g., network 22C of
FIG. 3). Act 16-0 comprises the wireless terminal making (e.g.,
measuring) or obtaining a determination of signal quality of a cell
of a third radio access technology network 22C (shown in FIG. 16 as
being in addition to the downlink determinations for network 22A
and network 22B). As a further act the wireless terminal transmits
an indication of the signal quality of a cell of the third radio
access technology network to the node of the first radio access
technology network (act 16-1).
[0115] In the particular embodiment and mode shown in FIG. 16, as
act 16-1 the indication of the signal quality of a cell of the
third radio access technology network is also included in the proxy
link report message (e.g., proxy link report message MRM2) which is
sent to the node of the first radio access technology network. In
another example embodiment and mode shown in FIG. 17, as act 17-0
the wireless terminal includes the indication of the signal quality
of a cell of the third radio access technology network in a
wireless terminal separate link report message (MRMS) which is sent
to the node of the first radio access technology network separately
from the proxy link report message. In the mode of FIG. 17 the
wireless terminal separate link report message of act precedes the
proxy link report message MRM2 (act 17-1), but as illustrated in
FIG. 18 the wireless terminal separate link report message MRMS can
(as act 18-2) succeed (follow in time) the proxy link report
message MRM2 (act 18-1).
[0116] FIG. 19 illustrates example, representative acts or steps
comprising a basic method of operating a communication system such
as communication system 20 of FIG. 2. Act 19-1 comprises a base
station node of the second radio access technology network (e.g.,
base station 28B of FIG. 2) performing a quality determination with
respect to an uplink transmission from a wireless terminal (e.g.,
wireless terminal 30). Act 19-2 comprises the base station node of
the second radio access technology network including an indication
of the quality determination in a link report message (e.g., link
report message MRM1) transmitted on a downlink from to the wireless
terminal. Act 19-3 comprises the wireless terminal then including
an indication of the quality determination in a proxy link report
message (e.g., proxy link report message MRM2). Act 19-4 comprises
the wireless terminal transmitting (relaying) the proxy link report
message to a node of the first radio access technology network
(e.g., to base station control node 26A of network 22A of FIG. 2).
Act 19-5 comprises the node of the first radio access technology
network using the quality determination with respect to the uplink
transmission from the wireless terminal (as included in the proxy
link report message) to determine whether to perform a radio access
technology handover procedure.
[0117] Act 19-4 comprises the wireless terminal also providing, as
a home network quality link report to the node of the first radio
access technology network, an indication of a quality determination
regarding a transmission between a wireless terminal and the first
radio access technology network.
[0118] In an example embodiment and mode illustrated in FIG. 20,
and in addition to acts 19-1 and 19-2, as act 20-1 the wireless
terminal makes a determination (e.g., measurement) of a quality
determination regarding a transmission between the wireless
terminal and the first radio access technology network. As act 20-2
the wireless terminal also includes, in the proxy link report
message, the indication of the quality determination regarding a
transmission between the wireless terminal and the first radio
access technology network. As act 20-3 the control node of the
first radio access technology network also uses (in addition to the
indications utilized in act 19-5) the indication of the signal
quality between the wireless terminal and the first radio access
technology network to determine whether to perform the radio access
technology handover procedure.
[0119] In yet another example embodiment and mode illustrated in
FIG. 21, and in addition to acts 19-1 and 19-2, as act 21-1 the
wireless terminal includes the indication of at least one of the
downlink quality determinations in a wireless terminal separate
link report message which is sent to the node of the first radio
access technology network separately from the proxy link report
message. As understood from previous discussions and figures, the
proxy link report message can either precede or follow the separate
link report message. Moreover, the downlink (DL) determinations
performed by wireless terminal 30 can occur either before or after
receipt of the second network measurement report message MRM1.
[0120] In an example embodiment and mode illustrated in FIG. 22,
and in addition to acts 19-1 and 19-2, the method further comprises
as act 22-1 the wireless terminal determining (e.g., measuring) or
obtaining signal quality of a cell of a third radio access
technology network 22C (shown in FIG. 22 as being in addition to
the downlink determinations for network 22A and network 22B). As a
further act 22-2 the wireless terminal transmits an indication of
the signal quality of the third radio access technology network
(e.g., of a cell of the third radio access technology network) to
the node of the first radio access technology network. As act 22-3
the node of the first radio access technology network also uses the
indication of the signal quality of the third radio access
technology network to determine whether to perform the radio access
technology handover procedure. The determination of act 22-3 can
use other indications such as those of act 19-5 and act 20-3.
[0121] In the particular embodiment and mode shown in FIG. 22, as
act 22-2 the indication of the signal quality of the third radio
access technology network is also included in the proxy link report
message (e.g., proxy link report message MRM2) which is sent to the
node of the first radio access technology network. In another
example embodiment and mode shown in FIG. 23, as act 23-3 the
wireless terminal includes the indication of the signal quality of
a cell of the third radio access technology network in a wireless
terminal separate link report message which is sent to the node of
the first radio access technology network separately from the proxy
link report message of act 23-2. In the mode of FIG. 23 the
wireless terminal separate link report message of act 23-3 succeeds
the proxy link report message MRM2 (act 23-2), but it should also
be appreciated that the wireless terminal separate link report
message can 23-3 precede (be earlier in time) the proxy link report
message MRM2 of act 23-2. As act 23-4 the node of the first radio
access technology network also uses the indication of the signal
quality of the third radio access technology network to determine
whether to perform the radio access technology handover procedure.
The determination of act 23-4 can use other indications such as
those of act 19-5 and act 20-3.
[0122] It should also be understood by the person skilled in the
art that, although herein described in the context of the 3GPP
radio technologies GSA, WCDMA, and LTE, the technology disclosed
herein may equally well be used in any other combination of radio
technologies including IEEE 802.11 technologies (WiFi), IEEE 802.16
systems (WiMAX), cdma systems described in 3GPP'' or any other
radio technology using cellular structures and handoff
technology.
[0123] An advantage of the technology disclosed herein is a better
quality of the voice and data services for mobile stations moving
around in a multitude of radio networks. In particular the
technology disclosed herein leads to more accurate decisions for
handoffs to better cells when a mobile station enters a region of
poor radio quality in the service cells. In an example preferred
embodiment with a combined GSM, WCDMA and LTE network the
technology disclosed herein will lead to inclusion of uplink
quality measurements for the LTE data service in the evaluation
algorithm for when to handoff from the combined GSM/LTE networks to
the WCDMA network.
[0124] Another advantage of the technology disclosed herein is a
reduction in number of dropped voice calls in a combined
GSM/WCDMA/LTE system.
[0125] Yet another advantage is a better mobile data service in a
multi-technology radio network.
[0126] One additional advantage of the technology disclosed herein
is that it reduces the number of unnecessary handoffs between
different radio technology networks.
[0127] The functions, events, steps, or acts described above may be
implemented by units including those aforementioned, which can be
computer-implement or preformed by a processor or controller as
those terms are herein expansively defined.
[0128] Although the description above contains many specificities,
these should not be construed as limiting the scope of the
invention but as merely providing illustrations of some of the
presently preferred embodiments of this invention. Thus the scope
of this invention should be determined by the appended claims and
their legal equivalents. Therefore, it will be appreciated that the
scope of the present invention fully encompasses other embodiments
which may become obvious to those skilled in the art, and that the
scope of the present invention is accordingly to be limited by
nothing other than the appended claims, in which reference to an
element in the singular is not intended to mean "one and only one"
unless explicitly so stated, but rather "one or more." All
structural, chemical, and functional equivalents to the elements of
the above-described preferred embodiment that are known to those of
ordinary skill in the art are expressly incorporated herein by
reference and are intended to be encompassed by the present claims.
Moreover, it is not necessary for a device or method to address
each and every problem sought to be solved by the present
invention, for it to be encompassed by the present claims.
Furthermore, no element, component, or method step in the present
disclosure is intended to be dedicated to the public regardless of
whether the element, component, or method step is explicitly
recited in the claims. No claim element herein is to be construed
under the provisions of 35 U.S.C. 112, sixth paragraph, unless the
element is expressly recited using the phrase "means for."
* * * * *