U.S. patent application number 11/538080 was filed with the patent office on 2007-05-10 for paging for a radio access network having pico base stations.
This patent application is currently assigned to Telefonaktiebolaget LM Ericsson (publ). Invention is credited to Tomas Nylander, Jari Vikberg.
Application Number | 20070105568 11/538080 |
Document ID | / |
Family ID | 37906409 |
Filed Date | 2007-05-10 |
United States Patent
Application |
20070105568 |
Kind Code |
A1 |
Nylander; Tomas ; et
al. |
May 10, 2007 |
PAGING FOR A RADIO ACCESS NETWORK HAVING PICO BASE STATIONS
Abstract
Methods and apparatus provide paging control to a femto radio
base station (28.sub.fj) of a radio access network (24). Paging to
a femto radio base station (28.sub.fj) is controlled by maintaining
a paging control database (46) of allowed user equipment units for
which paging is permitted in a cell of a femto radio base station
(28.sub.fj). The paging control database (46) is used to determine
if a paging message for a target user equipment unit is to be
forwarded to the femto radio base station. The database (46) thus
serves to redefine the effective paging area by preferably
including in the effective paging area only those femto radio base
station for which the target user equipment unit is listed as a
paging-allowed user equipment unit.
Inventors: |
Nylander; Tomas; (Varmdo,
SE) ; Vikberg; Jari; (Jarna, SE) |
Correspondence
Address: |
NIXON & VANDERHYE, PC
901 NORTH GLEBE ROAD, 11TH FLOOR
ARLINGTON
VA
22203
US
|
Assignee: |
Telefonaktiebolaget LM Ericsson
(publ)
Stockholm
SE
|
Family ID: |
37906409 |
Appl. No.: |
11/538080 |
Filed: |
October 3, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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60722983 |
Oct 4, 2005 |
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60722984 |
Oct 4, 2005 |
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60722982 |
Oct 4, 2005 |
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60723946 |
Oct 6, 2005 |
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60728780 |
Oct 21, 2005 |
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60731495 |
Oct 31, 2005 |
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Current U.S.
Class: |
455/458 |
Current CPC
Class: |
H04W 16/24 20130101;
H04W 88/085 20130101; H04W 48/16 20130101; H04L 61/1511 20130101;
H04W 24/02 20130101; H04W 80/04 20130101; H04W 84/045 20130101;
H04W 12/08 20130101; H04W 88/08 20130101; H04W 92/12 20130101; H04L
63/101 20130101; H04W 48/08 20130101; H04W 92/22 20130101; H04L
61/303 20130101; H04W 8/22 20130101; H04W 24/06 20130101; H04W
16/32 20130101; H04W 36/10 20130101; H04W 76/10 20180201; H04W
68/00 20130101; H04W 80/00 20130101; H04W 60/00 20130101; H04W
48/02 20130101; H04W 8/26 20130101 |
Class at
Publication: |
455/458 |
International
Class: |
H04Q 7/20 20060101
H04Q007/20 |
Claims
1. A method of operating a radio access network comprising:
maintaining a paging control database of allowed user equipment
units for which paging is permitted in a cell of a femto radio base
station; using the database to determine if a paging message for a
target user equipment unit is to be forwarded to the femto radio
base station.
2. The method of claim 1, further comprising using the database to
determine to which femto radio base station(s) a paging message
should be forwarded.
3. The method of claim 1, wherein the femto radio base station is
controlled by a radio network controller node, and further
comprising configuring the paging control database to associate,
for each of plural femto radio base stations controlled by the
radio network controller node, a list of allowed user equipment
units for which paging is permitted in the cell of the respective
femto radio base stations.
4. The method of claim 1, wherein the femto radio base station is
controlled by a radio network controller node, wherein the paging
message includes a network area identifier, and wherein the network
area identifier is associated with plural femto radio base stations
controlled by the radio network controller node.
5. The method of claim 4, wherein the network area identifier is
associated with all femto radio base stations controlled by the
radio network controller node.
6. The method of claim 4, wherein a subset of radio base stations
controlled by the radio network controller node consists of femto
radio base stations, and wherein the network area identifier is
associated the subset of femto radio base stations.
7. A method of operating a radio access network comprising:
maintaining a paging control database which associates, for each of
plural femto radio base stations, a list of allowed user equipment
units for which paging is permitted in the cell of the respective
femto radio base stations; upon receiving a paging message for a
target user equipment unit, using the database to redefine an
effective paging area for the target user equipment unit; and,
forwarding the paging message only to femto radio base stations
which are included in the effective paging area.
8. The method of claim 7, wherein the step of using the database to
redefine the effective paging area comprises including in the
effective paging area only those femto radio base station for which
the target user equipment unit is listed as a paging-allowed user
equipment unit.
9. The method of claim 7, wherein the femto radio base station is
controlled by a radio network controller node, wherein the paging
message includes a network area identifier, and wherein the network
area identifier is associated with plural femto radio base stations
controlled by the radio network controller node.
10. The method of claim 9, wherein the network area identifier is
associated with all femto radio base station controlled by the
radio network controller node.
11. The method of claim 9, wherein a subset of radio base stations
controlled by the radio network controller node consists of femto
radio base stations, and wherein the network area identifier is
associated the subset of femto radio base stations.
12. A radio access network comprising: a femto radio base station
for serving a femto cell of the radio access network; at least one
radio network controller node, the at least one radio network
controller node configured for controlling the femto radio base
station; a paging control database configured for facilitating a
determination whether a paging message received at the at least one
radio network controller node for a target user equipment unit is
to be forwarded to the femto radio base station.
13. The apparatus of claim 12, wherein the paging control database
is configured for facilitating a determination as to which femto
radio base station(s) a paging message should be forwarded.
14. The apparatus of claim 12, wherein the paging control database
is configured to associate, for each of plural femto radio base
stations controlled by the radio network controller node, a list of
allowed user equipment units for which paging is permitted in the
cell of the respective femto radio base stations.
15. The apparatus of claim 12, wherein the paging message includes
a network area identifier, and wherein the network area identifier
is associated with plural femto radio base stations controlled by
the radio network controller node.
16. The apparatus of claim 15, wherein the network area identifier
is associated with all femto radio base station controlled by the
radio network controller node.
17. The apparatus of claim 15, wherein a subset of radio base
stations controlled by the radio network controller node consists
of femto radio base stations, and wherein the network area
identifier is associated the subset of femto radio base
stations.
18. The apparatus of claim 12, wherein the paging control database
is situated as a stand alone node of the radio access network.
19. The apparatus of claim 12, wherein the paging control database
is situated at a radio network controller node of the radio access
network.
20. The apparatus of claim 12, wherein the paging control database
is configured for making the determination in response to
interrogation by the radio network controller node.
21. A radio access network comprising: at least one femto radio
base station, the at least one femto radio base station for serving
a respective femto cell of the radio access network; at least one
radio network controller node, the at least one radio network
controller node configured for controlling the at least one femto
radio base station and for receiving a paging message for a target
user equipment unit; a paging control database configured for
redefining an effective paging area for the target user equipment
unit; and wherein the at least one radio network controller node is
arranged for forwarding the paging message only to femto radio base
stations which are included in the effective paging area.
22. A radio access network node comprising a paging control
database, the paging control database being configured for
facilitating a determination whether a paging message received at a
radio network controller node for a target user equipment unit is
to be forwarded to the femto radio base station.
23. The apparatus of claim 22, wherein the paging control database
is situated as a stand alone node of the radio access network.
24. The apparatus of claim 22, wherein the paging control database
is situated at a radio network controller node of the radio access
network.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit and priority of the
following United States provisional patent applications (all of
which are incorporated herein by reference in their entirety):
[0002] U.S. Provisional Patent Application 60/722,983, entitled
"REDIRECTION OF IP-CONNECTED RBS TO THE CORRECT RNC";
[0003] U.S. Provisional Patent Application 60/722,984, entitled
"AUTOMATIC RNC SELECTION FOR IP-CONNECTED RBS";
[0004] U.S. Provisional Patent Application 60/722,982, entitled
FINE-GRAINED ACCESS CONTROL IN A WCDMA SYSTEM USING PICO BASE
STATIONS";
[0005] U.S. Provisional Patent Application 60/723,946, entitled
"PAGING FOR A WCDMA SYSTEM USING PICO BASE STATIONS";
[0006] U.S. Provisional Patent Application 60/728,780, entitled
"AUTOMATIC BUILDING OF NEIGHBOR LISTS IN A MOBILE SYSTEM"; and
[0007] U.S. Provisional Patent Application 60/731,495, entitled
"AUTOMATIC CONFIGURATION OF THE MACRO RADIO IN A PICO BASE
STATION".
[0008] This application is related to the following United States
patent applications (all of which are incorporated herein by
reference in their entirety):
[0009] U.S. patent application Ser. No. 11/______ (attorney docket:
2380-1024), filed on even date herewith, entitled "REDIRECTION OF
IP-CONNECTED RADIO BASE STATION TO CORRECT CONTROL NODE";
[0010] U.S. patent application Ser. No. 11/______ (attorney docket:
2380-1023), filed on even date herewith, entitled "RADIO NETWORK
CONTROLLER SELECTION FOR IP-CONNECTED RADIO BASE STATION";
[0011] U.S. patent application Ser. No. 11/______ (attorney docket:
2380-1022), filed on even date herewith, entitled "ACCESS CONTROL
IN A RADIO ACCESS NETWORK HAVING PICO BASE STATIONS";
[0012] U.S. patent application Ser. No. 11/______ (attorney docket:
2380-1019 filed on even date herewith, entitled "AUTOMATIC BUILDING
OF NEIGHBOR LISTS IN A MOBILE SYSTEM";
[0013] U.S. patent application Ser. No. 11/______ (attorney docket:
2380-1004, filed on even date herewith, entitled "AUTOMATIC
CONFIGURATION OF MACRO RECEIVER OF PICO RADIO BASE STATION";
and,
[0014] U.S. patent application Ser. No. 11/380,824, filed Apr. 28,
2006, entitled "DYNAMIC BUILDING OF MONITORED SET".
BACKGROUND
[0015] I. Technical Field
[0016] This invention pertains to wireless telecommunications, and
particularly to paging in a radio access network having pico or
"femto" radio base stations.
[0017] II. Related Art and Other Considerations
[0018] In a typical cellular radio system, wireless user equipment
units (UEs) communicate via a radio access network (RAN) to one or
more core networks. The user equipment units (UEs) can be mobile
stations such as mobile telephones ("cellular" telephones) and
laptops with 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. Alternatively, the wireless user equipment units
can be fixed wireless devices, e.g., fixed cellular
devices/terminals which are part of a wireless local loop or the
like.
[0019] 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. 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 a unique identity, which
is broadcast as system information in the cell. The base stations
communicate over the air interface with the user equipment units
(UE) within range of the base stations. In the radio access
network, several base stations are typically connected (e.g., by
landlines or microwave) to a radio network controller (RNC). The
radio network controller, also sometimes termed a base station
controller (BSC), 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.
The core network has two service domains, with an RNC having an
interface to both of these domains.
[0020] One example of a radio access network is the Universal
Mobile Telecommunications (UMTS) Terrestrial Radio Access Network
(UTRAN). The UMTS is a third generation system which in some
respects builds upon the radio access technology known as Global
System for Mobile communications (GSM) developed in Europe. UTRAN
is essentially a radio access network providing wideband code
division multiple access (WCDMA) to user equipment units (UEs). The
Third Generation Partnership Project (3GPP) has undertaken to
evolve further the UTRAN and GSM-based radio access network
technologies.
[0021] As those skilled in the art appreciate, in WCDMA technology
a common frequency band allows simultaneous communication between a
user equipment unit (UE) and plural base stations. Signals
occupying the common frequency band are discriminated at the
receiving station through spread spectrum CDMA waveform properties
based on the use of a high speed, pseudo-noise (PN) code. These
high speed PN codes are used to modulate signals transmitted from
the base stations and the user equipment units (UEs). Transmitter
stations using different PN codes (or a PN code offset in time)
produce signals that can be separately demodulated at a receiving
station. The high speed PN modulation also allows the receiving
station to advantageously generate a received signal from a single
transmitting station by combining several distinct propagation
paths of the transmitted signal. In CDMA, therefore, a user
equipment unit (UE) need not switch frequency when handover of a
connection is made from one cell to another. As a result, a
destination cell can support a connection to a user equipment unit
(UE) at the same time the origination cell continues to service the
connection. Since the user equipment unit (UE) is always
communicating through at least one cell during handover, there is
no disruption to the call. Hence, the term "soft handover." In
contrast to hard handover, soft handover is a "make-before-break"
switching operation.
[0022] Other types of telecommunications systems which encompass
radio access networks include the following: Global System for
Mobile communications (GSM); Advance Mobile Phone Service (AMPS)
system; the Narrowband AMPS system (NAMPS); the Total Access
Communications System (TACS); the Personal Digital Cellular (PDC)
system; the United States Digital Cellular (USDC) system; and the
code division multiple access (CDMA) system described in EIA/TIA
IS-95.
[0023] There are several interfaces of interest in the UTRAN. The
interface between the radio network controllers (RNCs) and the core
network(s) is termed the "Iu" interface. The interface between a
radio network controller (RNC) and its base stations (BSs) is
termed the "Tub" interface. The interface between the user
equipment unit (UE) and the base stations is known as the "air
interface" or the "radio interface" or "Uu interface". In some
instances, a connection involves both a Source and Serving RNC
(SRNC) and a target or drift RNC (DRNC), with the SRNC controlling
the connection but with one or more diversity legs of the
connection being handled by the DRNC. An Inter-RNC transport link
can be utilized for the transport of control and data signals
between Source RNC and a Drift or Target RNC, and can be either a
direct link or a logical link. An interface between radio network
controllers (e.g., between a Serving RNC [SRNC and a Drift RNC
[DRNC]) is termed the "Iur" interface.
[0024] The radio network controller (RNC) controls the UTRAN. In
fulfilling its control role, the RNC manages resources of the
UTRAN. Such resources managed by the RNC include (among others) the
downlink (DL) power transmitted by the base stations; the uplink
(UL) interference perceived by the base stations; and the hardware
situated at the base stations.
[0025] Those skilled in the art appreciate that, with respect to a
certain RAN-UE connection, an RNC can either have the role of a
serving RNC (SRNC) or the role of a drift RNC (DRNC). If an RNC is
a serving RNC (SRNC), the RNC is in charge of the connection with
the user equipment unit (UE), e.g., it has full control of the
connection within the radio access network (RAN). A serving RNC
(SRNC) is connected to the core network. On the other hand, if an
RNC is a drift RNC (DRNC), it supports the serving RNC (SRNC) by
supplying radio resources (within the cells controlled by the drift
RNC (DRNC)) needed for a connection with the user equipment unit
(UE). A system which includes the drift radio network controller
(DRNC) and the base stations controlled over the Tub Interface by
the drift radio network controller (DRNC) is herein referenced as a
DRNC subsystem or DRNS. An RNC is said to be the Controlling RNC
(CRNC) for the base stations connected to it by an Tub interface.
This CRNC role is not UE specific. The CRNC is, among other things,
responsible for handling radio resource management for the cells in
the base stations connected to it by the Tub interface.
[0026] Some operators are investigating the possibility of
providing home or small area WCDMA coverage for limited number of
users using a small radio base station ("RBS"), also called a
"Femto RBS" and/or a "Home RBS" and/or "pico RBS" and/or "micro
RBS" in some contexts. According to such investigation, the small
RBS would provide normal WCDMA coverage for the end users (e.g., to
a user equipment unit (UE)), and would be connected to the RNC
using some kind of IP based transmission. The coverage area so
provided is called a "femto cell" (to indicate that the coverage
area is relatively small). Other terminology for a femto cell
includes "pico cell" or "micro cell", which is in contrast to a
macro cell covered by a macro or standard radio base station
(RBS).
[0027] One alternative for the IP based transmission is to use
Fixed Broadband access (like xDSL, Cable etc.) to connect the home
RBS to the RNC. Another alternative would be to use Wireless
Broadband access (e.g. HSDPA and Enhanced Uplink; or WiMAX). FIG. 5
illustrates the two different backhaul alternatives in more detail.
The first alternative is labeled "xDSL Backhaul" and the second
alternative is labeled "WiMAX Backhaul".
[0028] In general, ordinary WCDMA base stations (macro RBS) are
able to connect to an RNC using IP-based transmission. Operator
personnel, e.g., employees of an operator company which owns or
maintains the macro RBS nodes and RNC nodes of the radio access
network (RAN), typically install the macro RBS nodes. As part of
the installation, the macro RBS is manually configured with IP
addressing information (DNS name, Fully Qualified Domain Name,
FQDN, or IP-address) of the RNC to which the macro RNC is to
connect.
[0029] By contrast, a femto RBS is typically installed by the end
user rather than the network operator. The end users are also able
to move the Femto RBS geographically from place to place without
the operator being able or willing to control relocation of the
femto RBS. Such user-directed relocation requires that, wherever
the Femto RBS is installed or located, it should connect to the
correct RNC. A "correct RNC" or "preferred RNC" in this sense would
be the same RNC that is controlling the overlaying macro cell of
the radio access network (RAN).
[0030] When the femto RBS is used to enhance local coverage for
example in a small or home office (SOHO) environment, it should be
dedicated to the home or enterprise since the transmission towards
the radio network controller node (and mobile core network) may be
using transmission provided and paid by the home or enterprise
itself. In such case the only terminals belonging to the SOHO or
enterprise should be allowed to access the femto radio base
stations.
[0031] In some situations the end user or SOHO purchases and
possibly operates the femto radio base station. In some instances
the femto radio base station may be a type of base stations that
can only serve a limited number of end users. In situations in
which there the femto radio base station has limited capacity or
ability to serve a limited number of users, it is important that
femto radio base station resources not be consumed with paging
operations for absent or eligible end users.
[0032] Given the considerations explained above, and as explained
further below, paging operations can play a role in gaining
end-user acceptance for the femto radio base station concept.
[0033] Paging is normally performed between a mobile station (MS)
(e.g., a user equipment unit (UE)) and the core network. Paging is
usually based on a concept known as Location Areas in the circuit
switched (CS) domain and a similar concept known as Routing Areas
in the packet switched (PS) domain). In the circuit switched (CS)
domain each Location Area is afforded a Location Area Identity
(LAI), while in the packet switched (PS) domain each Routing Area
is afforded a Routing Area Identity (RAI). Each MS/UE keeps track
of the last LAI and RAI where it last successfully performed
Location/Routing Area Update. The Radio Access Network (e.g. GERAN
or UTRAN) broadcasts the LAI and RAI in the system information for
each cell. A MS/UE can then compare this LAI/RAI with the previous
one and, if these differ, the Location/Routing Area update
procedures are triggered.
[0034] The core network keeps track of the MS/UE location on a
Location (and Routing) Area level. This means that when a MS/UE
terminating procedure is to be started, the network needs to
normally page the MS/UE in the whole Location Area.
[0035] Thus, it is understood that Location (and Routing) Area
planning is an important part of network configuration. Location
(and Routing) Area planning vastly affects the network performance
as, for example, in a large Location Area a MS/UE does not need to
perform Location (and Routing) Area Updates very often. As a
correlative disadvantage, however, the Paging Area is also very
wide when the Location (and Routing) Area is large. In such case,
one paging operation would need to be performed on multiple
BSCs/RNCs and base stations/cells. On the other hand, a small
Location Area means that a MS[UE will likely perform Location (and
Routing) Area Updates more often, but in an inverse sense the
magnitude of the paging operation is more optimized. However, in a
femto system, the handling of Location (and Routing) Areas is
totally different as the end users/femto operator installs the
femto radio base station.
[0036] Paging handling is problematic and sorely lacking for a
WCDMA system with femto radio base stations. The main reasons for
the problems and perplexities are the following:
[0037] Preferably, in a WCDMA network, a macro cell coverage and a
femto radio base station cell coverage does not have the same
LAI/RAI. A distinct LAI/RAI identifier is needed for the femto
cells compared to macro cells in order to provide reasonable access
control for a femto radio base station and to assure that a MS[UE
accessing a Femto-RBS will always initiate a Location Update
towards the Core Network. Techniques of access control for a femto
radio base station are described, e.g., in U.S. patent application
Ser. No. 11/______ (attorney docket: 2380-1022), filed on even date
herewith, entitled FINE-GRAINED ACCESS CONTROL IN A WCDMA SYSTEM
USING PICO BASE STATIONS".
[0038] Preferably, paging for a MS/UE connected to a femto radio
base station does not need to be sent to all femto radio base
stations. Paging in all femto radio base stations of a MS[UE
connected to one particular femto radio base station would create a
vast amount of traffic on the backhaul part connecting the femto
radio base station to the RNC and would degrade the total bandwidth
available. The backhaul is also in some cases paid and provided by
the end users and also used for other purposes.
[0039] It would initially seem that a simple solution to the paging
dilemma would be to assign each femto radio base station its own
LAI (and RAI). However, assigning a unique LAI and RAI to each
femto radio base station is also problematic. For example, the
maximum number of different LAIs for each Public Land Mobile
Network (PLMN) is 65535. The number of LA identifiers that can be
used for handling femto radio base station is less, as the same LAI
space is also used in the macro network. In addition, assigning a
unique LAI to each femto radio base station would impose large
operation and maintenance (O&M) overhead (considerable more
O&M tasks). Therefore LAIs/RAIs needs to be reused among the
femto radio base stations.
[0040] What is needed, therefore, and an object herein provided,
are method, technique, apparatus, or systems for providing
effective paging control to a femto radio base station in a radio
access network.
BRIEF SUMMARY
[0041] Methods and apparatus provide paging control to a femto
radio base station of a radio access network, e.g., for determining
in which femto radio base stations/cells to page a specific user
equipment unit. Paging with respect to a femto radio base
station/cell is controlled by maintaining a paging control database
of allowed user equipment units for which paging is permitted in a
cell of a femto radio base station. The paging control database is
used to determine if a paging message for a target user equipment
unit is to be forwarded to the femto radio base station.
[0042] The femto radio base station is typically controlled by a
radio network controller node. Preferably the paging control
database is configured to associate, for each of plural femto radio
base stations controlled by the radio network controller node, a
list of allowed user equipment units. For allowed user equipment
units on the list paging is permitted in the cell(s) of the
respective femto radio base station(s).
[0043] The paging message is first sent from the core network to
the radio access network and typically includes a network area
identifier (i.e. so called paging area) which is associated with
plural femto radio base stations controlled by the radio network
controller node. For example, in one implementation the network
area identifier is associated with all femto radio base station
controlled by the radio network controller node. In another
implementation, a subset of radio base stations controlled by the
radio network controller node consists of femto radio base
stations, and the network area identifier is associated the subset
of femto radio base stations.
[0044] In one of its aspects, the technology concerns methods of
operating a radio access network. One of the methods includes (1)
maintaining a paging control database which associates, for each of
plural femto radio base stations, a list of allowed user equipment
units for which paging is permitted in the cell of the respective
femto radio base stations; (2) upon receiving a paging message for
a target user equipment unit, using the database to redefine an
effective paging area for the target user equipment unit; and (3)
forwarding the paging message only to femto radio base stations
which are included in the effective paging area. The step of using
the database to redefine the effective paging area preferably
comprises including in the effective paging area only those femto
radio base stations for which the target user equipment unit is
listed as a paging-allowed user equipment unit.
[0045] Another aspect of the technology concerns a radio access
network comprising a femto radio base station for serving a femto
cell of the radio access network; at least one radio network
controller node configured for controlling the femto radio base
station; and, a paging control database. The paging control
database is configured for facilitating a determination whether a
paging message received at the at least one radio network
controller node for a target user equipment unit is to be forwarded
to the femto radio base station. In one sense, the paging control
database is configured for redefining an effective paging area for
the target user equipment unit. The paging control database can be
situated as a stand alone node of the radio access network or
situated at a radio network controller node of the radio access
network. Preferably the paging control database is configured for
making the determination in response to interrogation by the radio
network controller node.
[0046] Yet another aspect of the technology concerns a radio access
network node comprising a paging control database configured for
facilitating a determination whether a paging message received at a
radio network controller node for a target user equipment unit is
to be forwarded to the femto radio base station.
BRIEF DESCRIPTION OF THE DRAWINGS
[0047] 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.
[0048] FIG. 1A-FIG. 1E are diagrammatic views of an example
embodiment of a telecommunications system including a radio access
network, also illustrating example steps or events performed in
conjunction with paging control.
[0049] FIG. 2 is a schematic view of an example embodiment of a
femto radio base station.
[0050] FIG. 3 is a schematic view of a radio network control (RNC)
node.
[0051] FIG. 4 is a diagrammatic view of an example structure of
paging control database.
[0052] FIG. 5 is a diagrammatic view showing two different backhaul
alternatives.
[0053] FIG. 6 is a diagrammatic view of example steps or events
performed in conjunction with access control and paging control in
a radio access network which comprises femto radio base
stations.
DETAILED DESCRIPTION
[0054] 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.
[0055] Thus, for example, it will be appreciated by those skilled
in the art that block diagrams herein can represent conceptual
views of illustrative circuitry 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.
[0056] The functions of the various elements including functional
blocks labeled as "processors" or "controllers" may be provided
through the use of dedicated hardware as well as hardware capable
of executing software in association with appropriate software.
When provided by a processor, the functions may be provided by a
single dedicated processor, by a single shared processor, or by a
plurality of individual processors, some of which may be shared or
distributed. Moreover, explicit use of the term "processor" or
"controller" should not be construed to refer exclusively to
hardware capable of executing software, and may include, without
limitation, digital signal processor (DSP) hardware, read only
memory (ROM) for storing software, random access memory (RAM), and
non-volatile storage.
[0057] The present invention is described in the non-limiting,
example context of a telecommunications system 10 shown in FIG. 1A.
The telecommunications system 10 connects to a core network 20. The
telecommunications system 10 comprises a radio access network 24.
The radio access network 24 includes one or more radio network
controller nodes (RNCs) 26 and radio base stations (BS) 28. For
sake of example FIG. 1A particular shows two radio network control
nodes, i.e., a first radio network control 26.sub.1 and a second
radio network control 26.sub.2 as well as one or more macro radio
base stations (only one macro radio base station 28.sub.M being
shown in FIG. 1A) and plural femto radio base stations 28.sub.f1,
28.sub.f2, . . . 28.sub.fx. The macro radio base station 28.sub.M
serves a macrocell C.sub.M. The femto radio base stations
28.sub.f1, 28.sub.f2, . . . 28.sub.fx serve respective femtocells
C.sub.f1, C.sub.f2, . . . C.sub.fx. The person skilled in the art
understands that a radio base station is typically situated at an
interior (e.g., center) of the respective cell which the radio base
station serves, but for sake of clarity the macro radio base
station and femto radio base stations of FIG. 1A are shown instead
as being associated by double headed arrows to their respective
cells. At least some of the femtocells C.sub.f1, C.sub.f2, . . .
C.sub.fx are geographically overlayed or overlapped by the
macrocell C.sub.M.
[0058] As used herein, a "femto radio base station" also has the
meaning of a pico radio base station or a micro radio base station,
which serves a femto cell (or pico cell or micro cell). The femto
cell is typically overlaid by one or more macro cells and serves a
smaller geographic area or subscriber constituency than a macro
cell. The technology described herein has particular benefit for a
femto radio base station which can be installed and/or relocated
within a radio access network without the installation or
relocation being controlled by the owner/operator of the radio
access network. In other words, a non-network operator entity (a
femto operator) can acquire the femto radio base station and
situate the femto radio base station in accordance with the
preferences of the femto operator.
[0059] A user equipment unit (UE), such as user equipment unit (UE)
30 shown in FIG. 1A, communicates with one or more cells or one or
more base stations (BS) 28 over a radio or air interface 32. The
user equipment unit can be a mobile station such as a mobile
telephone ("cellular" telephone) and laptop with mobile
termination, and thus can be, for example, portable, pocket,
hand-held, computer-included, or car-mounted mobile device which
communicate voice and/or data with radio access network.
[0060] The radio access network 24 shown in FIG. 1A can be, by way
of non-limiting example, a UMTS Terrestrial Radio Access Network
(UTRAN). In the UTRAN, radio access is preferably based upon
Wideband Code Division Multiple Access (WCDMA) with individual
radio channels allocated using CDMA spreading codes. Of course,
other access methods may be employed. The nodes 26 and 28 are
respectively termed the radio network control node and the radio
base station nodes in view of the UTRAN example. However, it should
be understood that the term radio network control and radio base
station also encompasses nodes having similar functionality for
other types of radio access networks. Other types of
telecommunications systems which encompass other types of radio
access networks include the following: Global System for Mobile
communications (GSM); Advance Mobile Phone Service (AMPS) system;
the Narrowband AMPS system (NAMPS); the Total Access Communications
System (TACS); the Personal Digital Cellular (PDC) system; the
United States Digital Cellular (USDC) system; and the code division
multiple access (CDMA) system described in EIA/TIA IS-95.
[0061] The radio access network 24 is connected to core network 20
over an interface, such as the Iu interface for UTRAN. The core
network 20 of FIG. 1A can comprise, among other things a Mobile
Switching Center (MSC) node, a Gateway MSC node (GMSC), a Gateway
General Packet Radio Service (GPRS) support node (GGSN), and a
General Packet Radio Service (GPRS) Service (SGSN) node. Circuit
switched (CS) network or packet switched (PS) network can be
connected to core network 20.
[0062] For sake of simplicity, the radio access network 24 of FIG.
1A is shown with only two RNC nodes 26. Multiple radio network
controller nodes (RNCs) may be provided, with each RNC 26 being
connected to one or more base stations (BS) 28. It will be
appreciated that a different number of base stations than that
shown in FIG. 1A can be served by a radio network control 26, and
that RNCs need not serve the same number of base stations.
Moreover, an RNC can be connected over an Iur interface to one or
more other RNCs in radio access network 24. The radio network
controller node (RNC) 26 communicates over an interface Tub with
the macro radio base station 28M. Further, those skilled in the art
will also appreciate that a base station such as the macro radio
base station 28 is sometimes also referred to in the art as a radio
base station, a node B, or B-node. Each of the radio interface 32,
the Iu interface, the Iur interface, and the Tub interface are
shown by dash-dotted lines in FIG. 1A.
[0063] FIG. 1A further shows that the radio network controller
nodes (RNCs) of radio access network 24 have access to femto paging
control database 46. The femto paging control database 46 may be
provided as a separate node of radio access network 24 as shown, or
may be an adjunct of another RAN node (e.g., included in one or
more radio network controller nodes (RNCs) 26). Alternatively, in
certain cases, access to femto paging control database 46 can even
be provided through core network 20. In the particular radio access
network 24 shown in FIG. 1A, femto paging control database 46 is
shown as being connected to radio network control nodes, and
particularly to first radio network controller node RNC 26.sub.1
and second radio network controller node RNC 26.sub.2.
[0064] As shown by an example format depicted in FIG. 4, femto
paging control database 46 maintains or lists allowed user
equipment units for which paging is permitted in a cell of the
respective femto radio base station. The paging control database is
used to determine if a paging message for a target user equipment
unit is to be forwarded to the femto radio base station. As shown
in FIG. 4, femto paging control database 46 is formatted to list,
for each of L number of femto radio base stations, identifications
of the user equipment units which are permitted or allowed to be
paged for the respective femto radio base station. An example such
identification for a user equipment unit (UE) may be the
International Mobile Subscriber Identity (IMSI) of the user
equipment units.
[0065] FIG. 1A can be viewed as illustrating generic access of
femto radio base station 28.sub.fj to the radio access network
(RAN), e.g., to its radio network controller node (e.g., radio
network controller node 26.sub.1 in the specifically illustrated
scenario). By "generic access" is meant that the access afforded to
femto radio base station 28.sub.fj can be either broadband fixed
access or broadband wireless (mobile) access (e.g., WiMAX) as
described above. In broadband wireless (mobile) access, access for
femto radio base station 28.sub.fj to the radio access network 24
is through a macro radio base station, and can occur using, e.g.
High Speed Downlink Packet Access (HSDPA) and Enhanced Uplink; or
WiMAX. To cater generically to the access types, in FIG. 1A the
femto radio base stations 28.sub.f including femto radio base
stations 28.sub.fj are connected to a communications network 38. An
example of such communications network is an IP network 38. Unless
otherwise specifically exempted in its context, aspects of the
technology described herein are applicable to all types of access,
including broadband fixed access and broadband mobile access (e.g.,
broadband wireless access).
[0066] FIG. 2 illustrates basic, selected, representative
constituent elements of an example generic femto radio base station
28.sub.f. One or more of the femto radio base stations 28.sub.f1,
28.sub.f2, . . . 28.sub.fx can take the form of the generic femto
radio base station 28.sub.f shown of FIG. 2. The femto radio base
station 28.sub.f of FIG. 2 is shown as including, among its other
unillustrated constituent units, an interface unit 50 for
connecting with radio network control node 26 over an interface;
one or more radio frequency transceivers 52; and, a data processing
system, section, or unit 56.
[0067] The interface between femto radio base station 28.sub.f and
a radio network controller node can be, for example, the
conventional Iub interface as shown in FIG. 1A. Alternatively or
additionally, the interface between femto radio base station
28.sub.f and a radio network controller node can offer connectivity
to/through an IP networkand utilize, e.g., Internet Protocol
(IP)-based transmission.
[0068] The radio frequency transceivers 52 are for communicating
over the radio or air interface with user equipment units (UEs) in
the femtocell served by the femto radio base station 28.sub.f. The
number of radio frequency transceivers 52 depends on various
factors including capacity of the femto radio base station to
handle mobile connections.
[0069] FIG. 3 illustrates basic, selected, representative
constituent elements of an example radio network control node 26.
The radio network control node 26 can comprise several interface
units, such as an interface unit 70 for connecting radio network
control node 26 over the Iu interface to core network 20; an
interface unit 72 for connecting radio network control node 26 over
the Iur interface to other (unillustrated) radio network
controllers; one or more interface units 74 for connecting radio
network control node 26 over the Tub interface to respective one or
more macro radio base station 28.sub.M; and, one or more interface
units 76 for connecting radio network control node 26 to respective
one or more femto radio base stations 28.sub.f1, 28.sub.f2, . . .
28.sub.fx. The connection between RNC 26 and its radio base
station(s) can utilize, e.g., Internet Protocol (IP)-based and/or
ATM-based transmission.
[0070] In addition to interface units, the radio network control
node 26 comprises numerous unillustrated constituent units, as well
as a data processing system, section, or unit 80. As shown in FIG.
3, in an example, non-limiting implementation the data processing
system 80 of radio network control node 26 comprises a control
section (e.g., controller 82); a handover unit 84; a combiner and
splitter unit 86 (involved, e.g., in handling diversity legs of a
connection); a femto radio base station handler 88; and, a paging
handler 89. The femto radio base station handler 88 includes a
searcher interface 92 for femto paging control database 46.
[0071] The particular radio network controller node 26.sub.2
happens to control both macro radio base station 28.sub.M and femto
radio base stations 28.sub.f1, 28.sub.f2, . . . 28.sub.fx.
According to one aspect of the technology, the radio network
controller node 26.sub.2 is associated with two network area
identifiers: first network area identifier NAI.sub.26-M for use
with (e.g., in paging) the macro radio base stations (e.g., macro
radio base station 28.sub.M) and a second network area identifier
NAI.sub.26-f for use with (e.g., in paging) the femto radio base
stations (e.g., 28.sub.f1, 28.sub.f2, . . . 28.sub.fx). In this
respect, for sake of illustration FIG. 1A shows the femto radio
base stations (e.g., 28.sub.f1, 28.sub.f2, . . . 28.sub.fx) as
being bounded by or enclosed in an area depicted by dashed lined
labeled NAI.sub.26-f and the macro radio base station 28.sub.M as
being bounded by or enclosed in an area depicted by dashed line
NAI.sub.26-M.
[0072] As a precursor to describing use of paging control database
46, it is useful to describe other preliminary operations of radio
access network. At the time shown in FIG. 1A, user equipment unit
(UE) 30 is seeking access to radio access network 24 via femto
radio base station 28.sub.fj. The femto radio base station
28.sub.fj has been activated by a femto operator and has been
connected to a correct radio network controller node (e.g., radio
network controller 26.sub.2). The femto radio base station
28.sub.fj can become connected to is correct radio network
controller node in various ways, such as those explained, e.g., in
U.S. patent application Ser. No. 11/______ (attorney docket:
2380-1022), filed on even date herewith, entitled "REDIRECTION OF
IP-CONNECTED RBS TO THE CORRECT RNC"; and U.S. patent application
Ser. No. 11/______ (attorney docket: 2380-1023), filed on even date
herewith, entitled "AUTOMATIC RNC SELECTION FOR IP-CONNECTED RBS",
both of which are incorporated herein by reference.
[0073] In seeking access to radio access network 24 via femto radio
base station 28.sub.fj, the user equipment unit 30 attempting to
use femto radio base station 28.sub.fj for access to radio access
network 24, as generically represented by event or step S-1A in
FIG. 1A. One example way for user equipment unit 30 to attempt to
use femto radio base station 28.sub.fj for access to radio access
network 24 is by user equipment unit 30 attempting to establish a
radio resource control (RRC) connection (RRC connection
establishment) with radio access network 24 through femto radio
base station 28.sub.fj.
[0074] The actions of step S-1A of FIG. 1A and the area update
procedure are further described (as sub-steps) with reference to
FIG. 6. FIG. 6 shows, as sub-step S-1A-1, the candidate user
equipment unit 30 trying to camp on the cell of femto radio base
station 28.sub.fj, and in so doing the candidate user equipment
unit 30 detects a new network area identifier (e.g., a new LAI)
broadcast in the cell C.sub.fj of femto radio base station
28.sub.fj. A new network area identifier is an LAI which is
different than the previous LAI where a (location) updating
procedure was successful. In particular, for the illustrated
example, candidate user equipment unit 30 detects the network area
identifier NAI.sub.26-f. As sub-step S-1A-2 user equipment unit 30
sends a RRC connection establishment message to radio network
controller node 26.sub.2 via femto radio base station 28.sub.fj.
The RRC connection establishment message of sub-step S-1A-2
includes identification information regarding the user equipment
unit 30, e.g., the IMSI of candidate user equipment unit 30. As
part of sub-step S-1A-2, femto radio base station 28.sub.fj relays
the RRC connection establishment message over an appropriate
interface (e.g., the Tub interface) to radio network controller
26.sub.2.
[0075] Upon reception of the RRC connection establishment message
of sub-step S-1A-2, radio network controller node 26.sub.2, checks
paging control database 46 to find out whether user equipment unit
30 is a permitted user/subscriber/customer of femto radio base
station 28.sub.fj. In this regard, the check/query message of
sub-step S-1A-3 to femto paging control database 46 includes both
the identifier of the user equipment unit 30 and an identifier of
the femto radio base station 28.sub.fj for which permission is
sought. Thus, in the context of sub-step S-1A-3, the paging control
database 46 can also optionally serve as an access control data
base. In terms of also optionally being an access control database,
the database stores a list of allowed user equipment units which
are to be permitted access for use of a femto radio base station.
That is, the access control database is consulted and used to
determine if a candidate user equipment unit attempting to use the
femto radio base station for access to the radio access network is
to be given access. Use of paging control database 46 as an access
control database and access control for femto radio base station
28.sub.fj in general is described in more detail in U.S. patent
application Ser. No. 11/______ (attorney docket: 2380-1022), filed
on even date herewith, entitled "ACCESS CONTROL IN A RADIO ACCESS
NETWORK HAVING PICO BASE STATIONS". In the present scenario, it is
assumed that candidate user equipment unit 30 is a permitted or
allowed access to/via femto radio base station 28.sub.fj, and
accordingly an RRC connection establishment accepted message is
sent as illustrated by sub-step S-1A-4 of FIG. 6.
[0076] In view of the fact that RRC connection has been approved
and so notified, an area update operation is performed. By "area
update operation" is meant, for example, either a Location Area
Update (LAU) or a Routing Area Update (RAU), whichever is
appropriate. If, for example, the user equipment unit is attached
to the circuit switched (CS) domain of the core network 20, a
Location Area Update operation is performed as depicted by sub-step
S-1A-5A of FIG. 6. On the other hand, if the user equipment unit is
attached to the packet switched (PS) domain of the core network 20,
a Routing Area Update operation is performed as depicted by
sub-step S-1A-5B of FIG. 6. As shown in FIG. 6, a Location Area
Update operation is performed between user equipment unit 30 and a
Mobile Switching Center (MSC) node; a Routing Area Update operation
is performed between user equipment unit 30 and a SGSN node.
[0077] With an area update operation/procedure having been
performed for user equipment unit 30, the radio access network is
now in a position that user equipment unit 30 can be paged. FIG. 1B
and FIG. 6 in fact illustrates a paging message for user equipment
unit 30 being received as step or event S-1B. The paging message of
step or event S-1B, which seeks to page user equipment unit 30 as
its "target" or "paged" user equipment unit, can originate from,
e.g., core network 20. The paging message further specifies the
network area identifier (e.g., either the LAI or RAI) for the page,
e.g.,
[0078] NAI.sub.26-f.
[0079] Upon receipt of the paging message of step S-1B, radio
network controller node 26.sub.2 checks with femto paging control
database 46 to determine to exact which ones of the femto radio
base stations of the network area NA1.sub.26-f are to be involved
in the page, so that only the femto radio base stations to which
the user equipment unit 30 has access will be paged. The femto
radio base station handler 88 directs searcher interface 92 to
prepare a query of paging control database 46 so that radio network
controller node 26.sub.2 can ascertain for which femto radio base
stations in the area are eligible for paging user equipment unit
30. The query to paging control database 46 includes both the
identifier of the paged or target user equipment unit 30 and the
network area identifier for the area in which paging permission is
sought.
[0080] In the above regard, steps S-1C of FIG. 1C and of FIG. 6
show radio network controller node 26.sub.2 checking paging control
database 46 and obtaining therefrom a list of femto radio base
stations in network area NA1.sub.26-f which authorize or permit
paging for user equipment unit 30. In this regard, for the example
format of the paging control database 46 as shown in FIG. 4, the
returned list includes the identifiers of those femto radio base
stations which have the IMSI or other identifier of the target user
equipment unit mapped thereto or associated therewith.
[0081] Step S-1D of FIG. 1D and FIG. 6 show the ensuing step or
event of the paging message for target user equipment unit 30 being
forwarded to the femto radio base stations which permit paging to
user equipment unit 30. In the particular situation shown in FIG.
1D, for sake of easy of illustration only one femto radio base
station is permitted for paging, i.e., femto radio base station
28.sub.fj. It should be understood, however, that in other
situations it is entirely possible or even likely that the user
equipment unit 30 may be paged in two or more femto radio base
stations. For example, the same femto owner/operator may operate
two or more femto radio base stations, and grant access and paging
eligibility status to user equipment unit 30 in all femto radio
base station owned/operated by that femto owner/operator.
[0082] Step S-1E of FIG. 1E and FIG. 6 illustrate the paging
message to the target user equipment unit 30 being broadcasted in
the cell C.sub.fj of femto radio base station 28.sub.fj. If the
page for user equipment unit 30 had been permitted in other femto
radio base stations, the paging message for user equipment unit 30
would be broadcast in those other femto radio base stations as
well.
[0083] Thus, in one sense, femto paging control database 46 is
configured for redefining an effective paging area for the target
user equipment unit. Rather than the paging area being the entire
area NAI.sub.26-f as originally specified in the paging message of
step S-1B, as a result of performance of step S-1C the paging
control database 46 redefines and actually decreases the size of
the paging area to be only those cells for which paging to the
target user equipment unit 30 is permitted (as specified by the
table or listing of paging control database 46).
[0084] The paging control database 46 can be situated as a stand
alone node of the radio access network 24 as illustrated in FIG.
1A-FIG. 1E, or (alternatively) situated at a radio network
controller node of the radio access network. Preferably the paging
control database is configured for making the determination in
response to interrogation by the radio network controller node (as
occurred as part of step S-1C discussed above).
[0085] The femto paging control database 46 can be pre-configured
and/or dynamically configured with identities of allowed user
equipment units for which paging is to be permitted access for use
of the femto radio base station. In this regard, the femto radio
base station 28.sub.fj is identified in the RNC and in femto paging
control database 46 with an identifier such as (for example) a
serial number or the like. The association between serial number
and mobile subscriber identity (e.g., IMSI) is initially done, e.g.
at a store or other release point at which the pico-base station is
purchased or acquired by the pico/femto owner/operator.
Furthermore, it is also possible for the femto/pico owner/operator
of femto radio base station 28.sub.fj to define which mobile
subscribers (e.g., which user equipment units (UEs) are able to
access femto radio base station 28.sub.fj. Such control of access
(be it either remote, subsequent, and/or dynamic) can be achieved,
e.g., using a web-based service, where the owner of the base
station is first authorized and is then able to define the allowed
or permitted mobile subscribes. The mobile subscribers are
preferably identified using MSISDN number and then the service can
map these values to the IMSI values of the user equipment units for
use by the femto paging control database 46.
[0086] In the scenario described above with reference to FIG.
1A-FIG. 1E, the radio network controller node 26.sub.2 has control
of radio base stations including both macro radio base stations and
femto radio base stations, with a subset of the radio base stations
controlled by radio network controller node 26.sub.2 consisting of
the femto radio base stations 28.sub.f1, 28.sub.f2, . . .
28.sub.fx. The radio network controller node 26.sub.2 also has a
first network area identifier for its macro radio base stations,
and a different network area identifier for the subset of femto
radio base stations 28.sub.f1, 28.sub.f2, . . . 28.sub.fx. In other
implementations, however, a radio network controller node may be
dedicated to femto radio base stations (and thus control no macro
radio base stations), and accordingly have a network area
identifier which refers to all femto radio base stations under its
exclusive control.
[0087] Thus, the technology restricts paging of a target user
equipment unit only to those femto radio base stations desiring to
provide paging services for that particular user equipment unit.
Such dedication and exclusivity is especially important if, for
example, the end users' own broadband connection is used for
transmission between base station and RNC or if the end user has
paid for a certain WCDMA air capacity in the femto RBS.
[0088] Thus, as one aspect of the technology, a paging control
database is configured for facilitating a determination whether a
paging message received at a radio network controller node for a
target user equipment unit is to be forwarded to the femto radio
base station. In one implementation, the paging control database is
configured for actually making the determination.
[0089] Thus, in accordance with one aspect of the technology, a
MS/UE that is trying to camp on a cell handled by a femto radio
base station initiates a Location (and Routing) Area Update towards
the core network 20 (via the RNC/RBS or BSS). The RNC (or RBS) can
then apply access control at RRC connection establishment and
decide which MS[UEs are allowed to camp on the femto radio base
station. When the RNC (or RBS in some scenarios) receives a circuit
switched or packet switched paging message from the core network
20, it can perform a database query to paging control database 46
to find out which femto radio base stations a MS/UE is allowed to
use. Then paging is forwarded to only those femto radio base
stations. This means that the Paging Area is decreased from all
femto radio base stations to only those that a particular MS/UE is
allowed to use.
[0090] The foregoing principle/method can also be applied for radio
technologies other than WCDMA, which is illustrated only as an
example. Other suitable technologies include but are not limited to
GSM, CDMA, WiMAX etc. The technology has particular relevance of
the aforementioned and conveniently described system and scenarios,
but could also be applied in other cases and for other
networks.
[0091] As another example implementation, a number of (e.g.,
plural) LAIs (and RAIs) is assigned in the RNC for all the femto
radio base stations under its control. When a femto radio base
station connects to the RNC, the femto radio base station is
automatically assigned one of these LAIs. These LAI assignments can
be, for example, in round-robin manner so that each LAI contains
almost an equal number of femto radio base stations. An advantage
of this particular implementation is that no further changes are
needed in the network. The amount of unnecessary Paging traffic
decreases also, but still a large number of Femto-RBSs needs to be
paged when searching for a specific UE.
[0092] In the technology described herein, Paging Areas are
decreased from all femto radio base stations to only those that a
particular MS/UE is allowed to use. This means that no extra and
unnecessary traffic is created on the backhaul between the femto
radio base stations and the RNC.
[0093] In todays WCDMA systems, the Radio Resource Control (RRC)
protocol is terminated in the RNC. RRC handles the Paging towards
the MS/UE. In a future system the RRC or equivalent radio control
protocol may be terminated in the actual base station. Thus, within
the scope of the present technology is the fact that paging control
database 46 may reside in or being queried from other nodes.
[0094] Although various embodiments have been shown and described
in detail, the claims are not limited to any particular embodiment
or example. None of the above description should be read as
implying that any particular element, step, range, or function is
essential. The invention is not to be limited to the disclosed
embodiment, but on the contrary, is intended to cover various
modifications and equivalent arrangements.
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