U.S. patent application number 15/297528 was filed with the patent office on 2017-02-09 for mobile communication system, base station, higher-order apparatus, gateway apparatus, communication method, and program.
This patent application is currently assigned to NEC CORPORATION. The applicant listed for this patent is Yoshio UEDA. Invention is credited to Koichi MOCHIZUKI, Yoshio UEDA.
Application Number | 20170041832 15/297528 |
Document ID | / |
Family ID | 43586095 |
Filed Date | 2017-02-09 |
United States Patent
Application |
20170041832 |
Kind Code |
A1 |
MOCHIZUKI; Koichi ; et
al. |
February 9, 2017 |
MOBILE COMMUNICATION SYSTEM, BASE STATION, HIGHER-ORDER APPARATUS,
GATEWAY APPARATUS, COMMUNICATION METHOD, AND PROGRAM
Abstract
A mobile communication system includes a first Home Node B
(HNB); a second HNB; and a HNB gateway (HNB-GW) that is connected
to a core network, wherein the first HNB is configured to
communicate with a user equipment (UE) before a relocation of intra
HNB-GW in which the UE is relocated from the first HNB to the
second HNB, wherein the second HNB is configured to communicate
with a user equipment (UE) after the relocation and send Iu-UP
Initialization comprising an RFCI information to the HNB-GW during
the relocation, and wherein the HNB-GW is configured to receive the
Iu-UP Initialization.
Inventors: |
MOCHIZUKI; Koichi; (Tokyo,
JP) ; UEDA; Yoshio; (Tokyo, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
UEDA; Yoshio |
Tokyo |
|
JP |
|
|
Assignee: |
NEC CORPORATION
Tokyo
JP
|
Family ID: |
43586095 |
Appl. No.: |
15/297528 |
Filed: |
October 19, 2016 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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14695877 |
Apr 24, 2015 |
9503937 |
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15297528 |
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13389396 |
Feb 7, 2012 |
9020508 |
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PCT/JP2010/059330 |
Jun 2, 2010 |
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14695877 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04W 88/08 20130101;
H04W 84/045 20130101; H04W 36/38 20130101; H04W 88/16 20130101;
H04W 36/0055 20130101; H04W 36/0022 20130101 |
International
Class: |
H04W 36/00 20060101
H04W036/00; H04W 36/38 20060101 H04W036/38 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 12, 2009 |
JP |
2009-187320 |
Claims
1. A mobile communication system comprising: a first Home Node B
(HNB); a second HNB; and a HNB gateway (HNB-GW) that is connected
to a core network, wherein the first HNB comprises a transceiver
configured to communicate with a user equipment (UE) and send a
first message, comprising Radio Access Bearer sub-Flow Combination
Indicator (RFCI) information, to the HNB-GW during an intra HNB-GW
relocation in which the UE is relocated from the first HNB to the
second HNB, wherein the HNB-GW comprises a transceiver configured
to receive the first message and to send a second message,
comprising the RFCI information, to the second HNB, and wherein the
second HNB comprises a transceiver configured to communicate with
the UE and to receive the second message.
2. A mobile communication system according to claim 1, wherein the
first message is a message that requests relocation.
3. The mobile communication system according to claim 1, wherein
the second message is a relocation request message.
4. The mobile communication system according to one of claim 1,
wherein the first message is a Direct Transfer message.
5. The mobile communication system according to one of claim 1,
wherein the second message is a Direct Transfer message.
6. The mobile communication system according to one of claim 1,
wherein the transceiver of the second HNB is configured to receive
the RFCI information without execution of an Iu-UP Initialization
procedure.
7. The mobile communication system according to one of claim 1,
wherein the transceiver of the second HNB is further configured to
send a Relocation Complete message to the HNB-GW.
8. The mobile communication system according to one of claim 1,
wherein the transceiver of the first HNB is further configured to
send an RRC Reconfiguration message to the UE during the relocation
and the transceiver of the second HNB is further configured to
receive an RRC Reconfiguration Complete message from the UE during
the relocation.
9. A second Home Node B (HNB), the second HNB comprising a
transceiver configured to: communicate with a user equipment (UE);
and receive a message comprising Radio Access Bearer sub-Flow
Combination Indicator (RFCI) information from a HNB gateway
(HNB-GW) that is connected to a core network, during an intra
HNB-GW relocation in which the UE is relocated from a first HNB to
the second HNB.
10. The second HNB according to claim 9, wherein the message is a
message that requests relocation.
11. The second HNB according to claim 9, wherein the message is a
relocation request message.
12. The second HNB according to claim 9, wherein the message is a
Direct Transfer message.
13. The second HNB according to claim 9, wherein the message is a
Direct Transfer message.
14. The second HNB according to claim 9, wherein the transceiver is
configured to receive the RFCI information without execution of an
Iu-UP Initialization procedure.
15. The second HNB according to one of claim 9, wherein the
transceiver is further configured to send a Relocation Complete
message to the HNB-GW.
16. The second HNB according to claim 9, wherein the transceiver is
further configured to receive an RRC Reconfiguration Complete
message from the UE during the relocation, and wherein an RRC
Reconfiguration message is sent from the first HNB to the UE during
the relocation.
17. A Home Node B gateway (HNB-GW) that is connected to a core
network, the HNB-GW comprising: a transceiver configured to receive
a first message, comprising Radio Access Bearer sub-Flow
Combination Indicator (RFCI) information, from a first HNB during
an intra HNB-GW relocation in which the UE is relocated from the
first HNB to a second HNB; wherein the transceiver is further
configured to send a second message, comprising the RFCI
information, to the second HNB.
18. The HNB-GW according to one of claim 17, wherein the
transceiver is configured to send the second message comprising the
RFCI information to the second HNB without execution of an Iu-UP
Initialization procedure
19. The HNB-GW according to claim 17, wherein the transceiver is
further configured to receive a Relocation Complete message from
the second HNB.
20. A user equipment (UE), the UE comprising: a transceiver
configured to communicate with a first Home Node B (HNB) and a
second HNB; a controller comprising a memory storing instructions
and a processor configured to execute the instructions and thereby
trigger an intra-HNB gateway (HNB-GW) relocation in which the UE is
relocated from the first HNB to the second HNB; wherein the
transceiver is further configured to receive a Radio Resource
Control (RRC) Reconfiguration message from the first HNB during the
relocation, and to send an RRC Reconfiguration Complete message to
the second HNB during the relocation, wherein the HNB-GW is
connected to a core network, and wherein, during the relocation, a
first message comprising Radio Access Bearer Sub-Flow Combination
Indicator (RFCI) information is sent from the first HNB to the
HNB-GW and a second message comprising the RFCI information is sent
from the HNB-GW to the second HNB.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application is a Continuation Application of
U.S. patent application Ser. No. 14/695,877, filed Apr. 24, 2015,
which is a continuation of Ser. No. 13/389,396, filed on Feb. 7,
2012, which is based on International Patent Application
PCT/JP2010/059330 and which claims priority from Japanese Patent
Application No. 2009-187320 filed on Aug. 12, 2009, the entire
contents of which are hereby incorporated by reference in their
entireties.
TECHNICAL FIELD
[0002] The present invention relates to a mobile communication
system, a base station, a higher-order apparatus, a gateway
apparatus, a communication method, and a program.
BACKGROUND ART
[0003] A mobile communication system that is made up from a Node-B
(base station), an RNC (Radio Network Controller), and a CN (Core
Network) is representative of an existing 3GPP (3rd Generation
Partnership Project) mobile communication system.
[0004] AMR (Adaptive Multi-Rate) can be offered as the voice data
encoding method in a mobile communication system of this
configuration. AMR is a method in which the rate of voice data is
altered dynamically according to line conditions.
[0005] In a mobile communication system that employs AMR, a
transcoder is established in the CN in order to make the rates of
encoding and decoding of voice data identical, and transcoding is
carried out by the transcoder as necessary.
[0006] Data frames of voice data that are encoded by AMR are made
up from a plurality of subframes having different data sizes. The
combination of this plurality of subframes differs according to the
rate of the voice data, and an RFCI (RAB sub-Flow Combination
Indicator) value is prescribed as an identifier for each of these
combinations. In other words, an RFCI value is defined for each
rate of voice data.
[0007] In a mobile communication system that employs AMR, RFCI
information is set as control information in voice encoding in each
Node-B. RFCI information includes information that identifies for
each RFCI value the structure of the data frame that is indicated
by that RFCI value, and more specifically, information relating to
the number of subflows that make up that data frame and the data
size for each sub-flow. In addition to AMR, RFCI information is
also used in Wide-Band AMR (wide-band voice codec) and CS streaming
services (such as Fax or modem communication).
[0008] When transmitting voice data that have been encoded at a
particular rate, a Node-B transmits voice data to which the RFCI
value that corresponds to this rate is appended to another Node-B,
and upon receiving voice data from another Node-B, decodes this
voice data at the rate that corresponds to the RFCI value that is
appended to the voice data.
[0009] When UE (User Equipment: a terminal) carries out voice
communication by way of two Node-Bs, if the RFCI information
between the two Node-Bs matches, each RFCI value in these two items
of RFCI information indicates a data frame of the same structure.
As a result, encoding/decoding of voice data can be carried out
between the two Node-Bs at the same rate without passing by way of
a transcoder in the CN. A mode of carrying out voice communication
without passing by way of a transcoder in this way is referred to
as "Transcoder-Free Operation (TrFO)." This mode is prescribed in
3GPP TS23.153 (Non-Patent Document 1).
[0010] If, on the other hand, the RFCI information between the two
Node-Bs does not match, data frames of different structure may be
indicated in these two items of RFCI information even though the
RFCI values are the same. In such cases, encoding/decoding of voice
data cannot be carried out at the same rate between the two Node-Bs
unless carried out by way of a transcoder, whereby voice
communication cannot be carried out while maintaining
transcoder-free operation (TrFO).
[0011] Accordingly, RFCI information between two Node-Bs is
preferably caused to match in order to implement voice
communication while maintaining transcoder-free operation
(TrFO).
[0012] However, movement of UE occurs frequently in a mobile
communication system, whereby RFCI information of the
movement-origin Node-B to which the UE is connected before movement
is believed to often fail to match the RFCI information of the
movement-destination Node-B to which the UE is connected after
movement.
[0013] 3GPP TS25.415 (Non-Patent Document 2) prescribes the
handover of RFCI information by means of a Iu-UP Initialization
message that is prescribed in Iu-UP (Iu interface user plane)
protocol by way of CN between the RNC in the event of SRNS (Serving
Radio Network Subsystem) relocation in which the RNC to which the
movement-origin Node-B of a UE is connected differs from the RNC to
which the movement-destination Node-B is connected.
LITERATURE OF THE PRIOR ART
Non-Patent Documents
[0014] Non-Patent Document 1: 3GPP TS 23.153 [0015] Non-Patent
Document 2: 3GPP TS 25.415 [0016] Non-Patent Document 3: 3GPP TS
25.413 [0017] Non-Patent Document 4: 3GPP TS 25.467 [0018]
Non-Patent Document 5: 3GPP TS 25.468 [0019] Non-Patent Document 6:
3GPP TS 25.469
SUMMARY OF THE INVENTION
Problem to be Solved by the Invention
[0020] However, mobile communication systems are currently being
investigated in 3GPP that are made up from compact base stations
for residences and small businesses referred to as HNB (Home
Node-B: compact base station), HNB GW (Home Node-Gateway), and a
CN. The configuration of such a mobile communication system is next
described in detail using FIG. 1.
[0021] Referring to FIG. 1, this mobile communication system
includes: UE 1, HNB-S 2, HNB-T 3, HNB-GW 4, CN 6 that includes CN
node 5, HNB-GW 7, and HNB-X8.
[0022] UE 1 is a 3rd Generation mobile portable telephone
(terminal).
[0023] HNB-S2 and HNB-T3, and HNB-X8 are small base stations for
residences or small offices.
[0024] HNB-S2 is the movement-origin HNB to which UE 1 is connected
before movement.
[0025] HNB-T3 is the movement-destination HNB to which UE 1 is
connected after movement.
[0026] HNB-X8 is an HNB that has under its control the UE (not
shown) that is the communication partner of UE 1.
[0027] HNB-GW 4 is a gateway apparatus that connects HNB-S2 and
HNB-T3 to CN 6, and HNB-GW 7 is the gateway apparatus that connects
HNB-X8 to CN 6.
[0028] CN 6 is a 3.sup.rd Generation mobile switched network.
[0029] CN node 5 is a core network apparatus such as an HMS (Home
NodeB Management System) or MSC (Mobile Switching Center) that is
provided in CN 6.
[0030] UE 1 moves from HNB-S2 to HNB-T3 that is subordinate to the
same HNB-GW 4. This type of movement is referred to as
"intra-HNB-GW relocation."
[0031] Before movement, UE 1 carries out voice communication with
UE that is subordinate to HNB-X 8 by way of HNB-S 2, HNB-GW 4, CN
6, HNB-GW 7, and HNB-X 8.
[0032] After movement, UE 1 carries out speech communication with
UE that is subordinate to HNB-X 8 by way of HNB-T 3, HNB-GW 4, CN
6, HNB-GW 7, and HNB-X 8.
[0033] In FIG. 1, the opposite system of the communication partner
of UE 1 is a 3GPP radio communication system made up of HNB-X
8/HNB-GW 7/CN 6, but this system may also be an existing 3GPP radio
communication system that is made up of Node-B/RNC/CN.
[0034] It is here assumed that HNB is installed by an individual
party and not a portable telephone business. As a result, although
subordinate to the same HNB-GW 4, HNB-S 2 and HNB-T 3 are assumed
to have different vendors.
[0035] As a result, it is easily conceivable that RFCI information
between HNB-S 2 and HNB-T 3 do not match at the time of the
occurrence of an intra-HNB-GW relocation between HNB-S 2 and HNB-T
3 by UE 1.
[0036] If the RFCI information does not match, the problem arises
that voice communication cannot be carried out while maintaining
transcoder-free operation (TrFO).
[0037] In 3GPP, discussion is ongoing regarding standardization of
the method of intra-HNB-GW relocation between HNB even in a mobile
communication system made up of HNB/HNB-GW/CN, but as yet no method
of solution has been proposed for a case in which RFCI information
between HNBs does not match.
[0038] It is therefore an object of the present invention to
provide a mobile communication system, a base station, a
higher-order apparatus, a gateway apparatus, a communication
method, and a program that enable voice communication while
maintaining transcoder-free operation (TrFO) even in the event of
intra-HNB-GW relocation between HNBs and thus solve the
above-described problems.
Means for Solving the Problem
[0039] The first mobile communication system of the present
invention is a mobile communication system that includes a
terminal, a movement-origin base station to which the terminal is
connected before movement, a movement-destination base station to
which the terminal is connected after movement, and a higher-order
apparatus that has the movement-origin base station and the
movement-destination base station under its control; wherein:
[0040] control information in voice encoding in the movement-origin
base station and the movement-destination base station is set in
advance;
[0041] the movement-origin base station includes the control
information of its own station in a first message and transmits the
first message to the higher-order apparatus; and
[0042] the higher-order apparatus includes the control information
of the movement-origin base station in a second message and
transmits the second message to the movement-destination base
station.
[0043] The second mobile communication system of the present
invention is a mobile communication system that includes a
terminal, a movement-origin base station to which the terminal is
connected before movement, a movement-destination base station to
which the terminal is connected after movement, and a gateway
apparatus that connects the movement-origin base station and the
movement-destination base station to a core network; wherein:
[0044] as control information in voice encoding in the
movement-origin base station and the movement-destination base
station, control information is set in advance for each identifier,
this control information identifying the structure of a data frame,
which is indicated by the identifier, of voice data that have been
voice-encoded;
[0045] the movement-origin base station includes the control
information of its own station in a first message and transmits the
first message to the gateway apparatus;
[0046] the movement-destination base station includes the control
information of its own station in a second message and transmits
the second message to the gateway apparatus; and
[0047] the gateway apparatus: stores the control information of the
movement-origin base station that is contained in the first message
and the control information of the movement-destination base
station that is contained in the second message; when the control
information of the movement-origin base station and the control
information of movement-destination base station do not match, upon
subsequent reception of voice data from the movement-destination
base station, converts the identifiers that are appended to the
voice data to identifiers that indicate data frames that have the
same construction in the control information of the movement-origin
base station; and transmits voice data to which the converted
identifiers have been appended to the core network.
[0048] The first base station of the present invention is a base
station of a movement origin to which a terminal is connected
before movement and includes:
[0049] a control unit in which control information in voice
encoding is set in advance and that includes the control
information of its own station in a message; and
[0050] a transceiver unit that transmits the message to a
higher-order apparatus.
[0051] The second base station of the present invention is
movement-destination base station to which a terminal is connected
after movement and includes:
[0052] a control unit to which control information in voice
encoding is set in advance; and
[0053] a transceiver unit that receives a first message that
contains the control information of a movement-origin base station
to which the terminal is connected before movement.
[0054] The higher-order apparatus of the present invention is a
higher-order apparatus that has under its control a movement-origin
base station to which a terminal is connected before movement and a
movement-destination base station to which the terminal is
connected after movement, the higher-order apparatus further
including:
[0055] where control information in voice encoding is set in
advance in the movement-origin base station and the
movement-destination base station, a transceiver unit that receives
a first message that contains the control information of the
movement-origin base station from the movement-origin base station;
and
[0056] a control unit that includes the control information of the
movement-origin base station in a second message, wherein the
transceiver unit transmits the second message to the
movement-destination base station.
[0057] The gateway apparatus of the present invention is a gateway
apparatus that connects a movement-origin base station to which a
terminal is connected before movement and a movement-destination
base station to which the terminal is connected after movement to a
core network; wherein:
[0058] as control information in voice encoding in the
movement-origin base station and the movement-destination base
station, control information is set in advance for each identifier,
this control information identifying the structure of a data frame,
which is indicated by the identifier, of voice data that have been
encoded;
[0059] the gateway apparatus further including:
[0060] a transceiver unit that both receives from the
movement-origin base station a first message that contains the
control information of the movement-origin base station and
receives from the movement-destination base station a second
message that contains the control information of the
movement-destination base station;
[0061] a memory unit that stores the control information of the
movement-origin base station that is contained in the first message
and the control information of the movement-destination base
station that is contained in the second message;
[0062] a control unit that, when the control information of the
movement-origin base station and the control information of the
movement-destination base station do not match, upon subsequent
reception of voice data from the movement-destination base station,
converts the identifiers that are appended to the voice data to
identifiers that indicate data frames that have the same structure
in the control information of the movement-origin base station;
and
[0063] a second transceiver unit that transmits voice data to which
the converted identifiers have been appended to the core
network.
[0064] The first communication method of the present invention is a
communication method realized by a mobile communication system that
includes a terminal, a movement-origin base station to which the
terminal is connected before movement, a movement-destination base
station to which the terminal is connected after movement, and a
higher-order apparatus that has under its control the
movement-origin base station and the movement-destination base
station; the communication method including steps of: the
movement-origin base station including control information in voice
encoding of its own station in a first message and transmitting the
first message to the higher-order apparatus; and the higher-order
apparatus including the control information of the movement-origin
base station in a second message and transmitting the second
message to the movement-destination base station.
[0065] The second communication method of the present invention is
a communication method realized by a mobile communication system
that includes a terminal, a movement-origin base station to which
the terminal is connected before movement, a movement-destination
base station to which the terminal is connected after movement, and
a gateway apparatus that connects the movement-origin base station
and the movement-destination base station to a core network; the
communication method including steps of:
[0066] the movement-origin base station: including in a first
message control, as control information in voice encoding in its
own station, control information for each identifier, this control
information identifying the structure of a data frame, which is
indicated by the identifier, of voice data that have undergone
voice encoding, and transmitting the first message to the gateway
apparatus;
[0067] the movement-destination base station including the control
information of its own station in a second message and transmitting
the second message to the gateway apparatus; the gateway apparatus
storing the control information of the movement-origin base station
that is contained in the first message and the control information
of the movement-destination base station that is contained in the
second message;
[0068] when the control information of the movement-origin base
station and the control information of the movement-destination
base station do not match, the gateway apparatus subsequently, upon
receiving voice data from the movement-destination base station,
converting the identifiers that are appended to the voice data to
identifiers that indicate data frames that have the same
construction in the control information of the movement-origin base
station; and
[0069] the gateway apparatus transmitting to the core network voice
data to which the converted identifiers have been appended.
[0070] The third communication method of the present invention is a
communication method realized by a movement-origin base station to
which a terminal is connected before movement and includes steps of
including control information in voice encoding in its own station
in a message, and transmitting the message to a higher-order
apparatus.
[0071] The fourth communication method of the present invention is
a communication method realized by a movement-destination base
station to which a terminal is connected after movement and
includes a step of receiving from a higher-order apparatus a first
message that contains control information in voice encoding of a
movement-origin base station to which the terminal was connected
before movement.
[0072] The fifth communication method of the present invention is a
communication method realized by a higher-order apparatus that has
under its control a movement-origin base station to which a
terminal is connected before movement and a movement-destination
base station to which the terminal is connected after movement and
includes steps of:
[0073] receiving from the movement-origin base station a first
message that contains control information in the voice encoding of
the movement-origin base station;
[0074] including the control information of the movement-origin
base station in a second message; and
[0075] transmitting the second message to the movement-destination
base station.
[0076] The sixth communication method of the present invention is a
communication method realized by a gateway apparatus that connects
a movement-origin base station, to which a terminal is connected
before movement and a movement-destination base station to which
the terminal is connected after movement, to a core network; the
communication method including steps of:
[0077] both: receiving from the movement-origin base station a
first message that contains, as control information in voice
encoding of the movement-origin base station, control information
for each identifier that identifies the construction of a data
frame, which is indicated by the identifier, of voice data that
have undergone voice encoding, and receiving from the
movement-destination base station a second message that includes
the control information of the movement-destination base
station;
[0078] storing the control information of the movement-origin base
station that is contained in the first message and the control
information of the movement-destination base station that is
contained in the second message;
[0079] when the control information of the movement-origin base
station and the control information of the movement-destination
base station do not match, upon subsequently receiving voice data
from the movement-destination base station, converting the
identifiers that are appended to the voice data to identifiers that
indicate data frames that have the same construction in the control
information of the movement-origin base station; and
[0080] transmitting to the core network voice data to which the
converted identifiers have been appended.
[0081] The first program of the present invention causes a
movement-origin base station to which a terminal is connected
before movement to execute procedures of:
[0082] including control information in the voice encoding of its
own station in a message; and
[0083] transmitting the message to a higher-order apparatus.
[0084] The second program of the present invention causes a
movement-destination base station to which a terminal is connected
after movement to execute a procedure of:
[0085] receiving from a higher-order apparatus a first message that
includes control information in voice encoding of a movement-origin
base station to which the terminal was connected before
movement.
[0086] The third program of the present invention causes a
higher-order apparatus that has under its control a movement-origin
base station to which a terminal is connected before movement and a
movement-destination base station to which the terminal is
connected after movement to execute procedures of:
[0087] receiving from the movement-origin base station a first
message that contains control information in voice encoding of the
movement-origin base station;
[0088] including in a second message the control information of the
movement-origin base station; and
[0089] transmitting the second message to the movement-destination
base station.
[0090] The fourth program of the present invention causes a gateway
apparatus that connects a movement-origin base station, to which a
terminal is connected before movement and a movement-destination
base station to which the terminal is connected after movement, to
a core network to execute procedures of:
[0091] both: receiving from the movement-origin base station a
first message that contains, as control information in voice
encoding of the movement-origin base station, control information
for each identifier that identifies the construction of a data
frame, which is indicated by the identifier, of voice data that
have undergone voice encoding, and receiving from the
movement-destination base station a second message that contains
the control information of the movement-destination base
station;
[0092] storing the control information of the movement-origin base
station that is contained in the first message and the control
information of the movement-destination base station that is
contained in the second message;
[0093] when the control information of the movement-origin base
station and the control information of the movement-destination
base station do not match, upon subsequently receiving voice data
from the movement-destination base station, converting identifiers
that are appended to the voice data to identifiers that indicate
data frames that have the same construction in the control
information of the movement-origin base station; and
[0094] transmitting to the core network voice data to which the
converted identifiers have been appended.
Effect of the Invention
[0095] According to the first mobile communication system of the
present invention, a movement-origin base station transmits control
information of its own station to a higher-order apparatus, and the
higher-order apparatus transmits the control information of the
movement-origin base station to the movement-destination base
station.
[0096] Accordingly, the movement-destination base station is able
to take over the control information from the movement-origin base
station and thus carry out voice communication while maintaining
transcoder-free operation (TrFO) without change in the event of
relocation between a movement-origin base station and a
movement-destination base station.
[0097] According to the second mobile communication system of the
present invention, when the control information of the
movement-origin base station and the control information of the
movement-destination base station do not match, a gateway apparatus
converts the identifiers that are appended to voice data that are
subsequently received from the movement-destination base station to
identifiers that indicate data frames that have the same
construction in the control information of the movement-origin base
station.
[0098] As a result, at the time of the occurrence of relocation
between a movement-origin base station and a movement-destination
base station, voice communication can be performed while
maintaining transcoder-free operation (TrFO) without alteration
even when control information is not handed over between the
movement-origin base station and the movement-destination base
station.
BRIEF DESCRIPTION OF THE DRAWINGS
[0099] FIG. 1 shows the configuration of a mobile communication
system that is made up of HNB/HNB-GW/CN.
[0100] FIG. 2 is a block diagram showing the internal configuration
of an HNB and a higher-order apparatus in the mobile communication
system of the first exemplary embodiment of the present
invention.
[0101] FIG. 3 is a sequence chart for describing the operation of
the mobile communication system of the first exemplary embodiment
of the present invention.
[0102] FIG. 4 is a block diagram showing the internal configuration
of the HNB and the HNB-GW in the mobile communication system of the
second exemplary embodiment of the present invention.
[0103] FIG. 5 is a sequence chart for explaining the operation of
the mobile communication system of the second exemplary embodiment
of the present invention.
[0104] FIG. 6 shows a RANAP: Relocation Required message that has
been modified by the second exemplary embodiment of the present
invention.
[0105] FIG. 7 shows a RANAP: Relocation Request message that has
been modified by the second exemplary embodiment of the present
invention.
[0106] FIG. 8 is a state transition chart of Iu-UP Protocol that
has been modified by the second exemplary embodiment of the present
invention.
[0107] FIG. 9 is a block diagram showing the internal configuration
of the HNB and HNB-GW in the mobile communication system of the
third exemplary embodiment of the present invention.
[0108] FIG. 10 is a sequence chart for explaining the operation of
the mobile communication system of the third exemplary embodiment
of the present invention.
[0109] FIG. 11 shows a RUA Direct Transfer message that has been
modified by the third exemplary embodiment of the present
invention.
[0110] FIG. 12 is a block diagram showing the internal
configuration of the HNB and HNB-GW in the mobile communication
system of the fourth exemplary embodiment of the present
invention.
[0111] FIG. 13 is a sequence chart for explaining the operation of
the mobile communication system of the fourth exemplary embodiment
of the present invention.
[0112] FIG. 14 is a sequence chart for explaining the operation of
the mobile communication system of the fifth exemplary embodiment
of the present invention.
[0113] FIG. 15 is a block diagram showing the internal
configuration of the CN node in the mobile communication system of
the sixth exemplary embodiment of the present invention.
[0114] FIG. 16 is a sequence chart for explaining the operation of
the mobile communication system of the sixth exemplary embodiment
of the present invention.
[0115] FIG. 17 is a block diagram showing the internal
configuration of the HNB and HNB-GW in the mobile communication
system of the seventh exemplary embodiment of the present
invention.
[0116] FIG. 18 is a sequence chart for explaining the operation of
the mobile communication system of the seventh exemplary embodiment
of the present invention.
[0117] FIG. 19 is a block diagram showing the internal
configuration of the HNB and HNB-GW in the mobile communication
system of the eighth exemplary embodiment of the present
invention.
[0118] FIG. 20 is a sequence chart for explaining the operation of
the mobile communication system of the eighth exemplary embodiment
of the present invention.
BEST MODE FOR CARRYING OUT THE INVENTION
[0119] Exemplary embodiments of the present invention are next
described with reference to the accompanying drawings.
[0120] In the exemplary embodiments described hereinbelow, the
overall configuration of the mobile communication system is similar
to the system shown in FIG. 1.
First Exemplary Embodiment
[0121] This exemplary embodiment is characterized by HNB-S 2, HNB-T
3, and a higher-order apparatus (hereinbelow referred to as
"higher-order apparatus 9") that is either HNB-GW 4 or CN node
5.
[0122] In the present exemplary embodiment, the RFCI information of
HNB-S 2 is reported from HNB-S 2 to HNB-T 3 by way of higher-order
apparatus 9.
[0123] Referring to FIG. 2, HNB-S 2 of the present exemplary
embodiment includes control unit 21A that includes the RFCI
information of HNB-S 2 in a first message and transceiver unit 22A
that transmits this first message to higher-order apparatus 9.
[0124] Higher-order apparatus 9 of the present exemplary embodiment
further includes transceiver unit 91A that receives the first
message from HNB-S 2 and control unit 92A that includes the RFCI
information contained in the first message in a second message,
transceiver unit 91A further transmitting the second message to
HNB-T 3.
[0125] In addition, HNB-T 3 of the present exemplary embodiment
includes transceiver unit 31A that receives the second message from
higher-order apparatus 9 and control unit 32A that initializes the
RFCI information of HNB-T 3 and sets (resets) it to the RFCI
information contained in the second message.
[0126] The operations of the mobile communication system of the
present exemplary embodiment are next described in conjunction with
the sequence chart shown in FIG. 3.
[0127] In Step S101, HNB-S 2 transmits a first message that
contains the RFCI information of HNB-S 2 to higher-order apparatus
9.
[0128] In Step S102, higher-order apparatus 9 transmits to HNB-T 3
a second message that contains the RFCI information that is
contained in the first message that was received from HNB-S 2.
[0129] In the present exemplary embodiment as described above,
HNB-T 3 is able to take over the RFCI information from HNB-S 2 by
way of higher-order apparatus 9, whereby the effect is obtained in
which voice communication can be carried on while maintaining
transcoder-free operation (TrFO) without alteration even in the
event of intra-HNB-GW relocation between HINB-S 2 and HNB-T 3.
Second Exemplary Embodiment
[0130] The present exemplary embodiment is an example that is more
specific than the first exemplary embodiment with higher-order
apparatus 9 as HNB-GW 4.
[0131] In the present exemplary embodiment, the RFCI information of
HNB-S 2 is reported from HNB-S 2 to HNB-T 3 by way of HNB-GW 4 by
means of an RANAP message.
[0132] Referring to FIG. 4, HNB-GW 4 of the present exemplary
embodiment includes: opposite HNB transceiver 41B, RANAP function
unit 42B, opposite CN transceiver 43B, Iu-UP frame control unit
44B, Iu-UP frame transfer unit 45B, and RFCI hold unit 46B. In FIG.
4, opposite HNB transceiver 41B makes up transceiver unit 91A of
FIG. 2, and the other function blocks make up control unit 92A of
FIG. 2.
[0133] HNB-S 2 of the present exemplary embodiment includes:
opposite HNB-GW transceiver 21B, RANAP function unit 22B, Iu-UP
frame control unit 23B, and Iu-UP frame transfer unit 24B. In FIG.
4, opposite HNB-GW transceiver 21B makes up transceiver unit 22A of
FIG. 2, and the other function blocks make up control unit 21A of
FIG. 2.
[0134] HNB-T 3 of the present exemplary embodiment includes:
opposite HNB-GW transceiver 31B, RANAP function unit 32B, Iu-UP
frame control unit 33B, and Iu-UP frame transfer unit 34B. In FIG.
4, opposite HNB-GW transceiver 31B makes up transceiver unit 31A of
FIG. 2, and the other function blocks make up control unit 32A of
FIG. 2.
[0135] Opposite HNB transceiver 41B includes an interface for
connecting HNB-S 2 and HNB-T 3 and carries out transmission and
reception of voice data with HNB-S 2 and HNB-T 3.
[0136] RANAP function units 22B, 32B, and 42B realize the RANAP
(Radio Access Network Application Part) protocol functions
prescribed by 3GPP TS25.413 (Non-Patent Document 3). For example,
RANAP function units 22B, 32B, and 42B have a function of
generating RANAP messages and a function of terminating RANAP
messages.
[0137] Opposite CN transceiver 43B has an interface for connecting
with CN node 5, and carries out the transmission and reception of
voice data with CN node 5.
[0138] Iu-UP frame control units 23B, 33B, and 44B realize the
Iu-UP protocol functions prescribed by 3GPP TS25.415 (Non-Patent
Document 2). For example, Iu-UP frame control units 23B, 33B, and
44B have the function of generating Iu-UP initialization messages
(hereinbelow abbreviated as "Iu-UP Init messages") and a function
of terminating Iu-UP Init messages. In addition, Iu-UP frame
control unit 44B has a function of reporting RFCI information that
is contained in Iu-UP Init messages to RFCI hold unit 46B and a
function of, in the event of a restart of Iu-UP Initialization,
issuing a request for comparison of RFCI information to RFCI hold
unit 46B.
[0139] Iu-UP frame transfer units 24B, 34B and 45B realize the
Iu-UP protocol functions prescribed by 3GPP TS25.415 (Non-Patent
Document 2). For example, Iu-UP frame transfer units 24B, 34B, and
45B have the function of transferring Iu-UP frame data.
[0140] RFCI hold unit 46B has the function of holding RFCI
information that is reported from Iu-UP frame control unit 44B and
the function of reporting comparison results based on the request
for comparison of RFCI information from Iu-UP frame control unit
44B.
[0141] Opposite HNB-GW transceivers 2111 and 31B have interfaces
for connecting with HNB-GW 4 and carry out transmission and
reception of voice data with HNB-GW 4.
[0142] Two current 3GPP provisions relating to the present
exemplary embodiment are next described.
(1) First Provision
[0143] 3GPP TS25.415 (Non-Patent Document 2) prescribes that RAB
parameters relating to radio access bearers (RAB) between UE and CN
be reported by RANAP messages between CN and RNC (HNB-GW). More
specifically, the RAB parameters are parameters (such as data
transfer rate, block size, error rate) of QoS (Quality of Service)
that accord with the type of service.
[0144] However, the RAB parameters are closely related to RFCI
information that is exchanged by means of Iu-UP Initialization
messages, and there is consequently a concern that a mismatching of
status will occur when there is modification of only RFCI
information unaccompanied by the modification of RAB parameters
(RAB Modification) due to the restarting of Iu-UP
Initialization.
[0145] As a result, in order to prevent the occurrence of this type
of procedure, 3GPP TS25.415 (Non-Patent Document 2) prescribes
that, except for RAB modification, restarting of Iu-UP
Initialization must not be implemented from the same SRNS (First
Provision).
[0146] If the function of handing over RFCI information by means of
an Iu-UP Initialization message in a mobile communication system
that is made up of existing Node-B/RNC/CN is applied to a mobile
communication system that is made up of an HNB/HNB-GW/CN, Iu-UP
Initialization is activated to CN 6 from each of HNB-S 2 and HNB-T
3 in FIG. 1. In this case, however, the reactivation of Iu-UP
Initialization is implemented by the same SRNS (HNB-GW 4) as seen
from CN 6, and the first provision is therefore violated.
(2) Second Provision
[0147] The above-described problem of the first provision can
conceivably be solved by terminating an Iu-UP Initialization
message at an HNB-GW (i.e., by not terminating at a CN).
[0148] In 3GPP TS25.467 (Non-Patent Document 4), however, there is
concern regarding the increase in signal processing and the
increased complexity of processing in HNB-GW when an Iu-UP message
is terminated at an HNB-GW, and it is therefore stipulated that
messages of Iu-UP protocol not be terminated at an HNB-GW (Second
Provision). As a result, when an Iu-UP Initialization message is
terminated at an HNB-GW, the second provision is violated.
[0149] The present exemplary embodiment enables the performance of
voice communication while maintaining transcoder-free operation
(TrFO) unchanged in the event of intra-HNB-GW relocation between
HNB-S 2 and HNB-T 3 without modifying the above-described first
provision and second provision.
[0150] The operations of the present exemplary embodiment are next
described in conjunction with the sequence chart shown in FIG.
5.
[0151] In Step S201, HNB-S 2 first begins a Relocation procedure
realized by transmitting to HNB-GW 4 a RANAP: Relocation Required
message that requests the movement of UE 1 from HNB-S 2.
[0152] In the present exemplary embodiment, RFCI information of an
Iu-UP Initialization message is added in a RANAP: Relocation
Required message of 9.1.9 of 3GPP TS25.413 (Non-Patent Document 3).
FIG. 6 shows a RANAP: Relocation Required message that has been
modified by the present exemplary embodiment. FIG. 6 shows only the
points that have been modified. In the RANAP: Relocation Required
message of the present exemplary embodiment, "RFCI" that is the
RFCI value, the "RCFI subflow" that is the number of subflows that
make up the data frames shown by this RFCI value, and the "Length
of Subflow" that is the data size for each subflow are added as
RFCI information.
[0153] HNB-GW 4 terminates the RANAP: Relocation Required message
at RANAP function unit 42B and obtains the RFCI information.
[0154] In Step S202, HNB-GW 4 further requests the securing of the
resources of HNB-T 3 by transmitting to HNB-T 3 a RANAP: Relocation
Request message requesting the movement of UE 1 to HNB-T 3.
[0155] In the present exemplary embodiment, when RFCI information
is contained in the RANAP: Relocation Required message in Step
S201, RANAP function unit 42B obtains the RFCI information and
includes this RFCI information in a RANAP: Relocation Request
message.
[0156] In other words, in the present exemplary embodiment, RFCI
information is added to a RANAP: Relocation Request message of
9.1.10 of 3GPP TS25.413 (Non-Patent Document 3). FIG. 7 shows the
RANAP: Relocation Request message that has been modified by the
present exemplary embodiment. FIG. 7 shows only those points that
have been modified. As with the RANAP: Relocation Required message
of FIG. 6, "RFCI" that is the RFCI value, "RFCI Subflow" that is
the number of subflows that make up the data frames that are
indicated by the RFCI value, and the "Length of Subflow" that is
the data size of each subflow are added as RFCI information to the
RANAP: Relocation Request message of the present exemplary
embodiment
[0157] HNB-T 3 terminates the RANAP: Relocation Request message at
RANAP function unit 32B. If RFCI information is contained in this
RANAP: Relocation Request message, HNB-T 3 initializes the RFCI
information of HNB-T 3 and resets it to the RFCI information
contained in the RANAP: Relocation Request message.
[0158] In this way, upon subsequently receiving uplink voice data
from UE 1 and downlink voice data from CN 6, HNB-T 3 is able to
correctly recognize not only the structure of data frames of the
voice data but also the rate by means of the RFCI values appended
to these voice data.
[0159] In the present exemplary embodiment, moreover, regarding the
state transitions of HNB-T 3, a condition is added for
transitioning directly from the "NULL" state to the "Support Mode
Data Transfer Ready" state in the Iu-UP Protocol state transition
chart of 3GPP TS25.415 (Non-Patent Document 2). FIG. 8 shows an
image of the Iu-UP Protocol state transition chart that has been
modified by the present exemplary embodiment. FIG. 8 shows that a
transition occurs directly from the "NULL" state to the "Support
Mode Data Transfer Ready" state upon reception of a RANAP:
Relocation Request message that contains RFCI information
("Intra-HNB-GW Relocation-Req" in FIG. 8).
[0160] Thus, upon receiving a RANAP: Relocation Request message,
HNB-T 3 takes this message as a trigger and causes the state of
Iu-UP frame transfer unit 33B to transition from the "NULL" state
to the "Support Mode Data Transfer Ready" state and thus enter a
state that allows transfer of Iu-UP frame data even without
executing the Iu-UP Initialization procedure.
[0161] In the present exemplary embodiment, the signal name that
causes transition from the "NULL" state to the "Support Mode Data
Transfer Ready" state is "Intra-HNB-GW Relocation-Req," but the
signal name is not limited to this name.
[0162] The following Steps S203.about.S211 are well known as one
proposal of an intra-HNB-GW relocation procedure that is currently
being investigated in mobile communication systems made up of
HNB/HNB-GW/CN and are not directly related to the present
invention.
[0163] After execution of Step S202, HNB-T 3 responds to the RANAP:
Relocation Request message by transmitting to HNB-GW 4 a RANAP:
Relocation Request ACK message in Step S203.
[0164] HNB-GW 4 next instructs the start of Relocation by
transmitting to HNB-S 2 a Relocation Command message in Step
S204.
[0165] HNB-S 2 then instructs reconfiguration of the radio channel
by transmitting to UE 1 an RRC: Reconfiguration message in Step
S205.
[0166] In Step S206, HNB-T 3 next detects UE 1 by synchronization
in radio Layer 1 and reports the detection of UE 1 by transmitting
a Relocation Detect message to HNB-GW 4.
[0167] In Step S207, UE 1 next reports the completion of the
assignment of radio resources by transmitting an RRC:
Reconfiguration Complete message to HNB-T 3.
[0168] In Step S208, HNB-T 3 then reports the completion of
Relocation by transmitting a RANAP: Relocation Complete message to
HNB-GW 4.
[0169] HNB-GW 4 next requests release of the resources of HNB-S 2
by transmitting to HNB-S 2 a RANAP: Iu Release Command message in
Step S209.
[0170] HNB-S 2 then reports that the resources of HNB-S 2 have been
released by transmitting to HNB-GW 4 a RANAP: Iu Release Complete
message in Step S210.
[0171] UE 1 subsequently transmits and receives voice data (user
data) with HNB-GW 4 by way of HNB-T 3 in Step S211.
[0172] In the present exemplary embodiment as described
hereinabove, HNB-S 2 reports the RFCI information of HNB-S 2 to
HNB-GW 4 by means of a RANAP: Relocation Required message, and
HNB-GW 4 reports the RFCI information of HNB-S 2 to HNB-T 3 by
means of a RANAP: Relocation Request message, whereby HNB-T 3 is
able to take over the RFCI information from HNB-S 2 without
executing an Iu-UP Initialization procedure.
[0173] In addition, HNB-T 3 takes the reception of the RANAP:
Relocation Request message from HNB-GW 4 as a trigger to transition
to a state that allows the transfer of voice data, whereby voice
data can be transmitted without executing an Iu-UP Initialization
procedure.
[0174] Accordingly, HNB-T 3 is able to take over RFCI information
from HNB-S 2 and transmit voice data without executing an Iu-UP
Initialization procedure, whereby voice communication can be
carried out while maintaining the transcoder-free operation (TrFO)
unchanged even in the event of intra-HNB-GW relocation between
HNB-S 2 and HNB-T 3.
[0175] In the present exemplary embodiment, moreover, because there
is no need for executing an Iu-UP Initialization procedure, there
is no need to modify the first provision that does not permit the
restarting of Iu-UP Initialization from the same SRNS (HNB-GW 4) in
3GPP.
[0176] Further, in the present exemplary embodiment, an Iu-UP
Initialization message need not be terminated at HNB-GW, and there
is consequently no need to modify the second provision that does
not permit an Iu-UP protocol message to be terminated in HNB-GW in
3GPP.
[0177] In addition, the present exemplary embodiment obtains the
following two advantages due to the use of RANAP messages in
reporting RFCI information:
(1) First Advantage
[0178] The termination of an RANAP message at an HNB and HNB-GW is
prescribed by 3GPP TS25.467 (Non-Patent Document 4). As a result,
the present exemplary embodiment has the advantage that when
functions relating to the present exemplary embodiment are added in
an RANAP message, there is no need for support by adding new
protocol.
(2) Second Advantage
[0179] Although an intra-HNB-GW relocation procedure in 3GPP is
currently being investigated, an RANAP message is typically used
for signals of this procedure. Thus, by adding functions relating
to the present exemplary embodiment to RANAP messages, the present
exemplary embodiment has the advantage of eliminating the need to
add new signals to the intra-HNB-GW relocation procedure.
Third Exemplary Embodiment
[0180] The present exemplary embodiment is an example in which the
first exemplary embodiment is made more specific with higher-order
apparatus 9 as HNB-GW 4.
[0181] In the present exemplary embodiment, the RFCI information of
HNB-S 2 is reported from HNB-S 2 to HNB-T 3 by way of HNB-GW 4 by
means of a Direct Transfer message of RANAP User Adaptation
(hereinbelow abbreviated as "RUA").
[0182] RUA is defined in 3GPP TS 25.468 (Non-Patent Document 5). In
addition, an RUA Direct Transfer message is a message used for
transferring an RANAP message.
[0183] Referring to FIG. 9, HNB-GW 4 of the present exemplary
embodiment differs from HNB-GW 4 of the second exemplary embodiment
shown in FIG. 4 in that RUA function unit 47B has been added. RUA
function unit 47B is one constituent element that makes up control
unit 92A of FIG. 2.
[0184] HNB-S 2 of the present exemplary embodiment differs from
HNB-S 2 of the second exemplary embodiment shown in FIG. 4 in that
RUA function unit 25B has been added. RUA function unit 25B is one
constituent element that makes up control unit 21A of FIG. 2.
[0185] HNB-T 3 of the present exemplary embodiment differs from
HNB-T 3 of the second exemplary embodiment shown in FIG. 4 in that
RUA function unit 35B has been added. RUA function unit 35B is one
constituent element that makes up control unit 32A of FIG. 2.
[0186] RUA function units 25B, 35B, and 47B realize RUA protocol
functions prescribed by 3GPP TS 25.468 (Non-Patent Document 5). For
example, RUA function units 25B, 35B, and 47B have the function of
generating RUA messages and the function of terminating RUA
messages.
[0187] The operations of the present exemplary embodiment are next
described in conjunction with the sequence chart shown in FIG.
10.
[0188] In Step S301, HNB-S 2 first starts a Relocation procedure by
transmitting to HNB-GW 4 an RANAP: Relocation Required message that
requests the movement of UE 1 from HNB-S 2.
[0189] At the time of transmitting an RANAP: Relocation Required
message in the present exemplary embodiment, an RUA Direct Transfer
message for transferring this RANAP: Relocation Required message is
transmitted at the same time.
[0190] Still further, in the present exemplary embodiment, RFCI
information of an Iu-UP Init message is added in the RUA Direct
Transfer message of 9.1.4 of 3GPP TS 25.468 (Non-Patent Document
5). FIG. 11 shows an RUA Direct Transfer message that has been
modified by the present exemplary embodiment. FIG. 11 shows only
those points that have been modified. In the RUA Direct Transfer
message of the present exemplary embodiment, "RFCI" that is an RFCI
value, "RCFI Subflow" that is the number of subflows that make up
the data frames that are indicated by RFCI values, and "Length of
Subflow" that is the data size of each subflow are added as RFCI
information.
[0191] HNB-GW 4 both terminates RANAP: Relocation Required messages
at RANAP function unit 42B and terminates RUA Direct Transfer
messages at RUA function unit 47B and obtains RFCI information.
[0192] In Step S302, HNB-GW 4 further requests the securing of the
resources of HNB-T 3 by transmitting to HNB-T 3 an RANAP:
Relocation Request message requesting the movement of UE 1 to HNB-T
3.
[0193] In the present exemplary embodiment, at the time of
transmitting an RANAP: Relocation Request message, an RUA Direct
transfer message for transferring this RANAP: Relocation Request
message is transmitted at the same time.
[0194] In the present exemplary embodiment, moreover, when RFCI
information is contained in the RUA Direct Transfer message in Step
S301, RUA function unit 47B obtains the RFCI information and
includes this RFCI information in an RUA Direct Transfer message.
The RUA Direct Transfer message at this time is the same as the
message shown in FIG. 11.
[0195] HNB-T 3 both terminates the RANAP: Relocation Request
message in RANAP function unit 32B and terminates the RUA Direct
Transfer message in RUA function unit 35B. If RFCI information is
contained in this RUA Direct Transfer message, HNB-T 3 initializes
the RFCI information of HNB-T 3 and resets it to the RFCI
information that is contained in the RUA Direct Transfer
message.
[0196] In this way, when HNB-T 3 subsequently receives uplink voice
data from UE 1 and downlink voice data from CN 6, HNB-T 3 is able
to correctly recognize not only the structure of the data frames of
the voice data but also the rate by means of the RFCI values that
are appended to the voice data.
[0197] In the present exemplary embodiment, moreover, in the state
transition chart (see FIG. 8) of Iu-UP Protocol of 3GPP TS 25.415
(Non-Patent Document 2) relating to the state transitions of HNB-T
3, a condition is added that an RUA Direct Transfer message that
contains RFCI information (represented as "Intra-HNB-GW
Relocation-Req" in FIG. 8) be received as a condition for
transitioning directly from the "NULL" state to the "Support Mode
Data Transfer Ready" state.
[0198] In this way, HNB-T 3 takes the reception of an RUA Direct
Transfer message as a trigger for causing the state of Iu-UP frame
transfer unit 33B to transition from the "NULL" state to the
"Support Mode Data Transfer Ready" state to enter a state that
allows transfer of Iu-UP frame data without executing an Iu-UP
Initialization procedure.
[0199] The processing of the following Steps S303-S311 is the same
as the processing of Steps S203-S211 of FIG. 5.
[0200] In the present exemplary embodiment as described
hereinabove, HNB-S 2 reports the RFCI information of HNB-S 2 to
HNB-GW 4 by means of an RUA Direct Transfer message and HNB-GW 4
reports the RFCI information of HNB-S 2 to HNB-T 3 by means of an
RUA Direct Transfer message, whereby HNB-T 3 is able to take over
the RFCI information from HNB-S 2 without executing an Iu-UP
Initialization procedure.
[0201] In addition, HINB-T 3 takes the reception of an RUA Direct
Transfer message from HNB-GW 4 as a trigger for transitioning to a
state that allows the transfer of voice data, whereby voice data
can be transmitted without executing an Iu-UP Initialization
procedure.
[0202] Accordingly, HNB-T 3 is able to take over the RFCI
information from HNB-S 2 and transmit voice data without executing
an Iu-UP Initialization procedure, whereby voice communication can
be carried out while maintaining transcoder-free operation (TrFO)
without change even in the event of an intra-HNB-GW relocation
between HNB-S 2 and HNB-T 3.
[0203] In addition, in the present exemplary embodiment, because
there is no need for executing an Iu-UP Initialization procedure,
there is no need to modify the first provision in 3GPP that does
not permit restarting of Iu-UP Initialization from the same SRNS
(HNB-GW 4).
[0204] Still further, in the present exemplary embodiment, because
there is no need to terminate an Iu-UP Initialization message at an
HNB-GW, there is also no need to modify the second provision that
does not permit terminating an Iu-UP protocol message at an
HNB-GW.
Fourth Exemplary Embodiment
[0205] The present exemplary embodiment is an example in which the
first exemplary embodiment is made more specific with higher-order
apparatus 9 as HNB-GW 4.
[0206] In the present exemplary embodiment, the RFCI information of
HNB-S 2 is reported from HNB-S 2 to HNB-T 3 by way of HNB-GW 4 by
means of a Home Node B Application Part (hereinbelow abbreviated as
"HNBAP") Relocation message.
[0207] An HNBAP is defined in 3GPP TS 25.469 (Non-Patent Document
6). An HNBAP Relocation message is not prescribed in 3GPP but is
well known as one plan in intra-HNB-GW relocation procedures that
are currently being investigated. HNBAP Relocation messages have no
direct relation to the present invention.
[0208] Referring to FIG. 12, HNB-GW 4 of the present exemplary
embodiment differs from HNB-GW 4 of the second exemplary embodiment
shown in FIG. 4 in that HNBAP function unit 48B has been added.
HNBAP function unit 48B is one constituent element that makes up
control unit 92A of FIG. 2.
[0209] In addition, HNB-S 2 of the present exemplary embodiment
differs from HNB-S 2 of the second exemplary embodiment shown in
FIG. 4 in that HNBAP function unit 26B has been added. HNBAP
function unit 26B is one constituent element that makes up control
unit 21A of FIG. 2.
[0210] HNB-T 3 of the present exemplary embodiment differs from
HNB-T 3 of the second exemplary embodiment shown in FIG. 4 in that
HNBAP function unit 36B has been added. HNBAP function unit 36B is
one constituent element that makes up control unit 32A of FIG.
2.
[0211] HNBAP function units 26B, 36B, and 48B execute the HNBAP
protocol functions prescribed in 3GPP TS 25.469 (Non-Patent
Document 6). For example, HNBAP function units 26B, 36B, and 48B
have a function of generating HNBAP messages and a function of
terminating HNBAP messages.
[0212] The operations of the present exemplary embodiment are next
described in conjunction with the sequence chart shown in FIG.
13.
[0213] In Step S401, HNB-S 2 first starts the Relocation procedure
by transmitting to HNB-GW 4 an HNBAP: Relocation Required message
that requests movement of UE 1 from HNB-S 2.
[0214] In the present exemplary embodiment, RFCI information of an
Iu-UP Init message is added in this HNBAP: Relocation Required
message. RFCI information can be added to the HNBAP: Relocation
Required message at this time, similar to, for example, FIG.
11.
[0215] HNB-GW 4 terminates the HNBAP: Relocation Required message
at HNBAP function unit 48B and obtains the RFCI information.
[0216] In Step S402, HNB-GW 4 further requests the securing of the
resources of HNB-T 3 by transmitting to HNB-T 3 an HNBAP:
Relocation Request message that requests the movement of UE 1 to
HNB-T 3.
[0217] In the present exemplary embodiment, when RFCI information
is contained in the HNBAP: Relocation Required message in Step
S401, HNBAP function unit 48B obtains the RFCI information and
includes this RFCI information in the HNBAP: Relocation Request
message. RFCI information can be added to the HNBAP: Relocation
Request message at this time, for example, as in FIG. 11.
[0218] HNB-T 3 terminates the HNBAP: Relocation Request message at
HNBAP function unit 36B. If RFCI information was contained in this
HNBAP: Relocation Request message, HNB-T 3 initializes the RFCI
information of HNB-T 3 and resets it to the RFCI information that
is contained in the HNBAP: Relocation Request message.
[0219] In this way, upon subsequently receiving uplink voice data
from UE 1 and downlink voice data from CN 6, HNB-T 3 is able to
correctly recognize by means of the RFCI values appended to the
voice data not only the structure of the data frames of the voice
data but also the rate.
[0220] Still further, in the present exemplary embodiment, in the
state transition chart (see FIG. 8) of Iu-UP protocol of 3GPP TS
25.415 (Non-Patent Document 2) relating to the state transitions of
HNB-T 3, a condition is added that an HNBAP: Relocation Request
message that contains RFCI information (shown as "Intra-HNB-GW
Relocation-Req" in FIG. 8) be received as a condition for
transitioning directly from the "NULL" state to the "Support Mode
Data Transfer Ready" state.
[0221] In this way, HNB-T 3 takes the reception of an HNBAP:
Relocation Request message as a trigger to cause the state of Iu-UP
frame transfer unit 33B to transition from the "NULL" state to the
"Support Mode Data Transfer Ready" state and thus enter a state
that allows transfer of Iu-UP frame data without executing an Iu-UP
Initialization procedure.
[0222] The processing of succeeding Steps S403-S411 is similar to
the processing of Steps S203.about.211 of FIG. 5.
[0223] In the present exemplary embodiment as described
hereinabove, HNB-S 2 reports the RFCI information of HNB-S 2 to
HNB-GW 4 by means of an HNBAP: Relocation Required message, and
HNB-GW 4 reports the RFCI information of HNB-S 2 to HNB-T 3 by
means of an HNBAP: Relocation Request message, whereby HNB-T 3 is
able to take over the RFCI information from HNB-S 2 without
executing an Iu-UP Initialization procedure.
[0224] In addition, HNB-T 3 takes the reception of an HNBAP:
Relocation Request message from HNB-GW 4 as a trigger for
transitioning to a state that allows transfer of voice data,
whereby voice data can be transmitted without executing an Iu-UP
Initialization procedure.
[0225] Accordingly, HNB-T 3 is able to take over the RFCI
information from HNB-S 2 and transmit voice data without executing
an Iu-UP Initialization procedure, and voice communication can
therefore be carried out while maintaining transcoder-free
operation (TrFO) unchanged even in the event of an intra-HNB-GW
relocation between HNB-S 2 and HNB-T 3.
[0226] In addition, the elimination of the need to execute an Iu-UP
Initialization procedure in the present exemplary embodiment
further eliminates the need to modify the first provision that does
not permit reactivation of Iu-UP Initialization from the same SRNS
(HNB-GW 4) in 3GPP.
[0227] Still further, the elimination of the need to terminate an
Iu-UP Initialization message in an HNB-GW in the present exemplary
embodiment eliminates the need to modify the second provision that
does not permit the termination of an Iu-UP protocol message in an
HNB-GW in 3GPP.
Fifth Exemplary Embodiment
[0228] The present exemplary embodiment is an example in which the
first exemplary embodiment is made more specific with higher-order
apparatus 9 as HNB-GW 4. In addition, the configuration of the
present exemplary embodiment is similar to the configuration of the
second exemplary embodiment shown in FIG. 4.
[0229] IN the present exemplary embodiment, HNB-GW 4 reports the
RFCI information of HNB-S 2 to HNB-T 3 by means of an Iu-UP Init
message at the time of processing Relocation of UE 1 from HNB-S 2
to HNB-T 3. The Iu-UP Init message is a message that is transmitted
and received between an HNB and HNB-GW when an HNB attempts to
establish communication with the HNB that has the terminal of the
communication partner of the UE under its control at times of, for
example, the occurrence of Relocation.
[0230] In Iu-UP Ver2 of 3GPP TS 25.415 (Non-Patent Document 2), the
transmission of an Iu-UP Init message from a CN to an RNC is
prescribed. However, this prescription assumes a mobile
communication system that is made up of existing 3GPP
Node-B/RNC/CN.
[0231] As a result, the transmission of an Tu-UP Init message from
CN to HNB-GW must be made possible even in a mobile communication
system that is made up of HNB/HNB-GW/CN, but 3GPP TS 25.467
(Non-Patent Document 4) stipulates that a message of Iu-UP protocol
not be terminated at an HNB-GW.
[0232] The present exemplary embodiment therefore modifies the
provisions of 3GPP and permits the termination of an Iu-UP message
at an HNB-GW.
[0233] The operations of the present exemplary embodiment are next
described in conjunction with the sequence chart of FIG. 14.
[0234] In FIG. 14, HNB-GW 4 is assumed to have obtained the RFCI
information of HNB-S 2 in advance. In other words, HNB-S 2 has
transmitted an Iu-UP Init message that contains the RFCI
information of HNB-S 2 to HNB-GW 4 at the time that communication
is established between HNB-S 2 and HNB-X 8, whereby HNB-GW 4 has
obtained the RFCI information of HNB-S 2. This procedure is
implemented before Step S501 of FIG. 14 and is not described in
FIG. 14.
[0235] First, the processing of Steps S501 and S502 that is similar
to the processing of Steps S201 and S202 of FIG. 5 is carried
out.
[0236] In Step S503, HNB-T 3 next transmits an Iu-UP Init message
that contains the RFCI information of HNB-T 3 to HNB-GW 4. HNB-GW 4
terminates the Iu-UP Init message in Iu-UP frame control unit 44B
and compares the RFCI information of HNB-T 3 that is contained in
the Iu-UP Init message with the RFCI information of HNB-S 2 that
was obtained beforehand.
[0237] In Step S504, HNB-GW 4 next responds to the Iu-UP Init
message by transmitting an Iu-UP Init ACK message to HNB-T 3.
[0238] If the RFCI information of HNB-S 2 and the RFCI information
of HNB-T 3 do not match in Step S503, HNB-GW 4 transmits an Iu-UP
Init message that contains the RFCI information of HNB-S 2 to HNB-T
3 in Step S505 to cause the RFCI information of HNB-T 3 to match
the RFCI information of HNB-S 2.
[0239] In Step S506, HNB-T 3 next responds to the Iu-UP Init
message by transmitting an Iu-UP Init ACK message to HNB-GW 4. In
addition, HNB-T 3 initializes the RFCI information of HNB-T 3 and
resets it to the RFCI information of HNB-S 2 that is contained in
the Iu-UP Init message.
[0240] The processing of succeeding Steps S507-S515 is similar to
the processing of Steps S203-S211 of FIG. 5.
[0241] In the present exemplary embodiment as described
hereinabove, HNB-GW 4 reports the RFCI information of HNB-S 2 to
HNB-T 3 by means of an Iu-UP Init message, whereby HNB-T 3 is able
to take over the RFCI information from HNB-S 2.
[0242] Accordingly, voice communication can be carried out while
maintaining transcoder-free operation (TrFO) unchanged even in the
event of an intra-HNB-GW relocation between HNB-S 2 and HNB-T
3.
[0243] The description in 7.2 of 3GPP TS 25.467 (Non-Patent
Document 4) that is modified by the present exemplary embodiment is
as shown below.
[0244] Iu-UP is terminated only at CN, HNB, and HNB-GW.
[0245] The description of Iu-UP Ver2 in 6.5.2 of 3GPP TS 25.415
(Non-Patent Document 2) that is modified by the present exemplary
embodiment is as shown below.
[0246] The initialization procedure can be controlled at two Iu
access points, i.e., both CN and UTRAN.
[0247] An Initialization procedure is activated when indicated by
the control function of Iu-UP procedures, i.e., at the time of
relocation of SRNS or when RAB is established on Iu, or when a CN
or HNB-GW attempts to resolve nonmatching of RFCI in the state of
carrying out TrFO. The Initialization procedure cannot be restarted
by an SRNC for RAB without requesting RAB Modification by means of
an RANAP.
[0248] Although the transmission of an Iu-UP Init message from an
RNC to a CN is prescribed in Iu-UP Ver1 of 3GPP TS 25.415
(Non-Patent Document 2), the transmission of an Iu-UP Init message
from a CN to an RNC is not prescribed. The prescription for Iu-UP
Ver1 may be amended similarly to Iu-UP Ver2.
[0249] In this case, the description of Iu-UP Ver1 in 6.5.2 of 3GPP
TS 25.415 (Non-Patent Document 2) that is modified by the present
exemplary embodiment is as shown below.
[0250] The Initialization procedure can be controlled at two Iu
access points, i.e., both CN and UTRAN.
[0251] The Initialization procedure is activated at the time
indicated by the control function of the Iu-UP procedure, i.e., at
the time of relocation of an SRNS or when establishing RAB on Iu,
or when a CN or an HNB-GW attempts to resolve nonmatching of RFCI
in a state of carrying out TrFO. The Initialization procedure
cannot be restarted by SRNC for RAB without requesting RAB
Modification by means of an RANAP.
Sixth Exemplary Embodiment
[0252] The present exemplary embodiment is an example in which the
first exemplary embodiment has been made more specific with
higher-order apparatus 9 as CN node 5.
[0253] In the present exemplary embodiment, CN node 5 reports the
RFCI information of HNB-S 2 to HNB-T 3 by means of an Iu-UP Init
message at the time of processing Relocation of UE 1 from HNB-S 2
to HNB-T 3.
[0254] In other words, in the present exemplary embodiment, CN node
5 carries out operations that were carried out by HNB-GW 4 in the
third exemplary embodiment, and HNB-GW 4 carries out only transfer
without terminating RANAP messages and Iu-UP Init messages that are
exchanged between HNB-S 2/HNB-T 3 and CN node 5.
[0255] However, the current 3GPP TS 25.415 (Non-Patent Document 2)
stipulates that the restarting of Iu-UP Initialization at the time
of occurrence of an intra-HNB-GW relocation is not permitted.
[0256] In response, the provisions of 3GPP are modified in the
present exemplary embodiment, and the reactivation of Iu-UP
Initialization is permitted even in the event of an intra-HNB-GW
relocation.
[0257] Referring to FIG. 15, CN node 5 of the present exemplary
embodiment includes: opposite HNB-GW transceiver 51C for HNB-GW 4,
RANAP function unit 52C, opposite HNB-GW transceiver 53C for HNB-GW
7, Iu-UP frame control unit 54C, Iu-UP frame transfer unit 55C, and
RFCI hold unit 56C. In FIG. 15, moreover, opposite HNB-GW
transceiver 51C makes up transceiver unit 91A of FIG. 2, and the
other function blocks make up control unit 92A of FIG. 2.
[0258] In addition, the configurations of HNB-S 2 and HNB-T 3 of
the present exemplary embodiment are similar to the configurations
of HNB-S 2 and HNB-T 3 of the second exemplary embodiment shown in
FIG. 4.
[0259] Opposite HNB-GW transceiver 51C has an interface for
connecting with HNB-GW 4 and transmits and receives voice data with
HNB-GW 4.
[0260] Opposite HNB-GW transceiver 53C has an interface for
connecting with HNB-GW 7 and transmits and receives voice data with
HNB-GW 7.
[0261] The remaining RANAP function unit 52C, Iu-UP frame control
unit 54C, Iu-UP frame transfer unit 55C, and RFCI hold unit 56C
perform operations similar to RANAP function unit 42B, Iu-UP frame
control unit 44B, Iu-UP frame transfer unit 45B, and RFCI hold unit
46B, respectively, shown in FIG. 4.
[0262] The operations of the present exemplary embodiment are next
described in conjunction with the sequence chart shown in FIG.
16.
[0263] In FIG. 16, it is assumed that CN node 5 has obtained the
RFCI information of HNB-S 2 in advance. In other words, at the time
that communication is established between HNB-S 2 and HNB-X 8,
HNB-S 2 transmits an Iu-UP Init message that contains the RFCI
information of HNB-S 2 to CN node 5 by way of HNB-GW 4, whereby CN
node 5 obtains the RFCI information of HNB-S 2. This procedure is
implemented before Step S601 of FIG. 16 and is not shown in FIG.
16.
[0264] First, processing that is similar to the processing carried
out by HNB-S 2, HNB-T 3, and HNB-GW 4 in Steps S201 and S202 of
FIG. 5 is carried out by HNB-S 2, HNB-T 3, and CN node 5 in Steps
S601 and S602.
[0265] HNB-T 3 next transmits an Iu-UP Init message that contains
the RFCI information of HNB-T 3 to CN node 5 by way of HNB-GW 4 in
Step S603. CN node 5 terminates the Iu-UP Init message at Iu-UP
frame control unit 54C and compares the RFCI information of HNB-T 3
that is contained in the Iu-UP Init message with the RFCI
information of HNB-S 2 that was obtained in advance.
[0266] In Step S604, CN node 5 next responds to the Iu-UP Init
message by transmitting an Iu-UP Init ACK message to HNB-T 3 by way
of HNB-GW 4.
[0267] If the RFCI information of HNB-S 2 and the RFCI information
of HNB-T 3 do not match in Step S603, CN node 5 transmits an Iu-UP
Init message that contains the RFCI information of HNB-S 2 to HNB-T
3 by way of HNB-G W 4 in Step S605 to cause the RFCI information of
HNB-T 3 to match the RFCI information of HNB-S 2.
[0268] In Step S606, HNB-T 3 next responds to the Iu-UP Init
message by transmitting an Iu-UP Init ACK message to CN node 5 by
way of HNB-GW 4. In addition, HNB-T 3 initializes the RFCI
information of HNB-T 3 and resets it to the RFCI information of
HNB-S 2 that is contained in the Iu-UP Init message.
[0269] The processing that is carried out by UE 1, HNB-S 2, HNB-T
3, and CN node 5 in the subsequent Steps S607.about.S615 is similar
to the processing that was carried out by UE 1, HNB-S 2, HNB-T 3,
and HNB-GW 4 in Steps S203-S211 of FIG. 5.
[0270] In the present exemplary embodiment as described
hereinabove, CN node 5 reports the RFCI information of HNB-S 2 to
HNB-T 3 by means of an Iu-UP Init message, whereby HNB-T 3 is able
to take over the RFCI information from HNB-S 2.
[0271] Accordingly, voice communication can be carried out while
maintaining transcoder-free operation (TrFO) unchanged even in the
event of an intra-HNB-GW relocation between HNB-S 2 and HNB-T
3.
[0272] In addition, the description of Iu-UP Ver1 in 6.5.2 of 3GPP
TS 25.415 (Non-Patent Document 2) that is modified by the present
exemplary embodiment is as follows:
[0273] The Initialization procedure cannot be reactivated for RAB
without requesting RAB Modification by means of an RANAP or without
the occurrence of intra-HNB-GW relocation.
[0274] In addition, the description of Iu-UP Ver2 at 6.5.2 of 3GPP
TS 25.415 (Non-Patent Document 2) that is modified by the present
exemplary embodiment is as follows:
[0275] The Initialization procedure cannot be reactivated for RAB
without requesting RAB Modification by means of an RANAP or without
the occurrence of intra-HNB-GW relocation.
Seventh Exemplary Embodiment
[0276] The mobile communication system of the present exemplary
embodiment is characterized by HNB-S 2, HNB-T 3, and HNB-GW 4.
[0277] In the present exemplary embodiment, each of HNB-S 2 and
HNB-T 3 reports RFCI information to HNB-GW 4, and when the RFCI
information of HNB-S 2 and the RFCI information of HNB-T 3 do not
match, HNB-GW 4 converts the RFCI values that are appended to voice
data received from HNB-T 3 to RFCI values that indicate data frames
that have the same structure in the RFCI information of HNB-S
2.
[0278] Referring to FIG. 17, HNB-S 2 of the present exemplary
embodiment includes: control unit 21D that includes the RFCI
information of HNB-S 2 in a first message, and transceiver unit 22D
that transmits this first message to HNB-GW 4.
[0279] In addition, HNB-T 3 of the present exemplary embodiment
includes: control unit 31D that includes the RFCI information of
HNB-T 3 in a second message, and transceiver unit 32D that
transmits this second message to HNB-GW 4.
[0280] HNB-GW 4 of the present exemplary embodiment includes: first
transceiver unit 41D that both receives a first message from HNB-S
2 and receives a second message from HNB-T 3; storage unit 42D that
stores RFCI information of HNB-S 2 that is contained in the first
message and RFCI information of HNB-T 3 that is contained in the
second message; control unit 43D that, when the RFCI information of
HNB-S 2 and the RFCI information of HNB-T 3 do not match, upon
subsequent reception of voice data from HNB-T 3, converts the RFCI
values that are appended to the voice data to RFCI values that
indicate data frames having the same construction as the voice data
in the RFCI information of HNB-S 2; and second transceiver unit 44D
that transmits to CN 6 the voice data to which have been appended
the RFCI values that underwent RFCI-conversion in control unit
43D.
[0281] The operations of the mobile communication system of the
present exemplary embodiment are next described in conjunction with
the sequence chart shown in FIG. 18.
[0282] In Step S701, HNB-S 2 transmits a first message that
contains the RFCI information of HNB-S 2 to HNB-GW 4.
[0283] In Step $702, HNB-T 3 transmits a second message that
contains the RFCI information of HNB-T 3 to HNB-GW 4.
[0284] HNB-GW 4 stores the RFCI information of HNB-S 2 that is
contained in the first message and the RFCI information of HNB-T 3
that is contained in the second message in storage unit 42D. In
addition, HNB-GW 4 further compares the RFCI information of HNB-S 2
and HNB-T 3.
[0285] UE 1 subsequently carries out transmission and reception of
voice data (user data) with HNB-GW 4 by way of HNB-T 3 in Step
S703.
[0286] When the RFCI information of HNB-S 2 and the RFCI
information of HNB-T 3 do not match at this time, HNB-GW 4 upon
reception of voice data from HNB-T 3 carries out the
RFCI-conversion of the RFCI values that are appended to the voice
data to RFCI values that indicate data frames that have the same
construction as the voice data in the RFCI information of HNB-S
2.
[0287] HNB-GW 4 then transmits the voice data to which the
converted RFCI values have been appended to CN 6.
[0288] When the RFCI information of HNB-S 2 and HNB-T 3 match,
HNB-GW 4 transmits the voice data that were received from HNB-T 3
and the RFCI values that were appended to the voice data to CN 6
without alteration.
[0289] When the RFCI information of HNB-S 2 and the RFCI
information of HNB-T 3 do not match in the present exemplary
embodiment as described hereinabove, HNB-GW 4 subsequently converts
RFCI values that are appended to voice data that are received from
HNB-T 3 to the RFCI values that indicate data frames that have the
same construction in the RFCI information of HNB-S 2.
[0290] As a result, even when RFCI information is not handed over
between HNB-S 2 and HNB-T 3, voice communication can be carried out
while maintaining transcoder-free operation (TrFO) without change
in the event of intra-HNB-GW relocation between HNB.
Eighth Exemplary Embodiment
[0291] The present exemplary embodiment is an example in which the
seventh exemplary embodiment has been made more specific.
[0292] In the present exemplary embodiment, each of HNB-S 2 and
HNB-T 3 reports RFCI information to HNB-GW 4 by means of Iu-UP Init
messages, and when the RFCI information of HNB-S 2 and the RFCI
information of HNB-T 3 do not match, HNB-GW 4 converts the RFCI
values that are appended to voice data that are received from HNB-T
3 to the RFCI values that indicate data frames that have the same
construction in the RFCI information of HNB-S 2.
[0293] However, UTRAN architecture for 3G Home Node B of 3GPP TS
25.467 (Non-Patent Document 4) prescribes that a message of Iu-UP
protocol not be terminated in an HNB-GW.
[0294] The 3GPP prescription is therefore modified in the present
exemplary embodiment and the termination of an Iu-UP message in an
HNB-GW is permitted.
[0295] Referring to FIG. 19, HNB-GW 4 of the present exemplary
embodiment includes: opposite HNB transceiver 41E, RANAP function
unit 42E, opposite CN transceiver 43E, Iu-UP frame control unit
44E, Iu-UP frame transfer unit 45E, RFCI hold unit 46E, and RFCI
conversion unit 47E. In FIG. 19, opposite HNB transceiver 41E
constitutes first transceiver unit 41D of FIG. 17, opposite CN
transceiver 43E constitutes second transceiver unit 44D of FIG. 17,
RFCI hold unit 46E constitutes storage unit 42D of FIG. 17, and the
other function blocks make up control unit 43B of FIG. 17.
[0296] In addition, HNB-S 2 of the present exemplary embodiment
includes: opposite HNB-GW transceiver 21E, RANAP function unit 22E,
Iu-UP frame control unit 23E, and Iu-UP frame transfer unit 24E. In
FIG. 19, opposite HNB-GW transceiver 21E constitutes transceiver
unit 22D of FIG. 17, and the other function blocks make up control
unit 21D of FIG. 17.
[0297] In addition, HNB-T 3 of the present exemplary embodiment
includes opposite HNB-GW transceiver 31E, RANAP function unit 32E,
Iu-UP frame control unit 33E, and Iu-UP frame transfer unit 34E. In
FIG. 19, opposite HNB-GW transceiver 31E constitutes transceiver
unit 32D of FIG. 17, and the other function blocks make up control
unit 31D of FIG. 17.
[0298] RFCI conversion unit 47E has the function of carrying out an
RFCI conversion of converting the RFCI values that are appended to
voice data that are received from HNB-T 3 to RFCI values that
indicate data frames that have the same construction in the RFCI
information of HNB-S 2.
[0299] In HNB-GW 4, the other opposite HNB transceiver 41E, RANAP
function unit 42E, opposite CN transceiver 43E, Iu-UP frame control
unit 44E, Iu-UP frame transfer unit 45E, and RFCI hold unit 46E
each carry out the same operations as opposite HNB transceiver 41B,
RANAP function unit 42B, opposite CN transceiver 43B, Iu-UP frame
control unit 44B, Iu-UP frame transfer unit 45B, and RFCI hold unit
46B, respectively, shown in FIG. 4.
[0300] In HNB-S 2, opposite HNB-GW transceiver 21E, RANAP function
unit 22E, Iu-UP frame control unit 23E, and Iu-UP frame transfer
unit 24E, each carry out operations similar to opposite HNB-GW
transceiver 21B, RANAP function unit 22B, Iu-UP frame control unit
23B, and Iu-UP frame transfer unit 24B, respectively, shown in FIG.
4.
[0301] In HNB-T 3, opposite HNB-GW transceiver 31E, RANAP function
unit 32E, Iu-UP frame control unit 33E, and Iu-UP frame transfer
unit 34E each carry out operations similar to opposite HNB-GW
transceiver 31B, RANAP function unit 32B, Iu-UP frame control unit
33B, and Iu-UP frame transfer unit 34B, respectively, shown in FIG.
4.
[0302] The operations of the present exemplary embodiment are next
described in conjunction with the sequence chart shown in FIG.
20.
[0303] In FIG. 20, HNB-GW 4 is assumed to obtain the RFCI
information of HNB-S 2 in advance. In other words, HNB-S 2
transmits to HNB-GW 4 an Iu-UP Init message that contains the RFCI
information of HNB-S 2 at the time communication is established
between HNB-S 2 and HNB-X 8, whereby HNB-GW 4 acquires the RFCI
information of HNB-S 2. This procedure is implemented before Step
S801 of FIG. 20 and is not described in FIG. 20.
[0304] The processing of Steps S801 and S802 that is similar to the
processing of Steps S201 and S202 of FIG. 5 is first carried
out.
[0305] In Step S803, HNB-T 3 next transmits to HNB-GW 4 an Iu-UP
Init message that contains the RFCI information of HNB-T 3. HNB-GW
4 terminates the Iu-UP Init message at Iu-UP frame control unit 44E
and compares the RFCI information of HNB-T 3 that is contained in
the Iu-UP Init message with the RFCI information of HNB-S 2 that
was acquired beforehand.
[0306] In Step S804, HNB-GW 4 next responds to the Iu-UP Init
message by transmitting to HNB-T 3 an Iu-UP Init ACK message.
The processing of Steps S805.about.S812 that are similar to Steps
S203.about.S211 of FIG. 5 is then carried out, following which UE 1
transmits and receives voice data (user data) with HNB-GW 4 by way
of HNB-T 3 in Step S813.
[0307] Here, if the RFCI information of HNB-S 2 and the RFCI
information of HNB-T 3 do not match in Step S803, the RFCI
information of HNB-T 3 and HNB-X 8 also do not match. In such
cases, RFCI values that are the same in the two sets of RFCI
information of HNB-T 3 and HNB-X 8 may nevertheless indicate data
frames having different structures, and RFCI conversion is
therefore necessary for voice data that are transmitted in from UE
1 by way of HNB-T 3.
[0308] As a result, HNB-GW 4 transfers voice data that have been
transmitted in from UE 1 by way of HNB-T 3 to RFCI conversion unit
47E from Iu-UP frame transfer unit 45E; and at RFCI conversion unit
47E, RFCI-conversion is implemented to convert the RFCI values that
are appended to these voice data to RFCI values that indicate data
frames that have the same construction as the voice data in the
RFCI information of HNB-S 2. Voice data to which RFCI values, that
have undergone RFCI conversion, are then transferred to Iu-UP frame
transfer unit 45E and transmitted to CN 6 by way of opposite CN
transceiver 43E.
[0309] When the RFCI information of HNB-S 2 and the RFCI
information of HNB-T 3 do not match in the present exemplary
embodiment as described hereinabove, HNB-GW 4 subsequently converts
the RFCI values that are appended to the voice data that were
received from HNB-T 3 to RFCI values that indicate data frames that
have the same construction in the RFCI information of HNB-S 2.
[0310] As a result, voice communication can be carried out while
maintaining transcoder-free operation (TrFO) without alteration in
the event of intra-HNB-GW relocation between HNB even when RFCI
information is not handed over between HNB-S 2 and HNB-T 3.
[0311] The description at 7.2 of 3GPP TS 25.467 (Non-Patent
Document 4) that is modified by the present exemplary embodiment is
as shown below.
[0312] Iu-UP is terminated only at CN, HNB, and HNB-GW.
[0313] Although the present invention has been described with
reference to exemplary embodiments, the present invention is not
limited to the above-described exemplary embodiments. The
constitution and details of the present invention are open to
various modifications within the scope of the present invention
that will be clear to one of ordinary skill in the art.
[0314] For example, in the first to fourth exemplary embodiments,
the control information that was handed over from HNB-S 2 to HNB-T
3 was described only as RFCI information, but the present invention
is not limited to this form, and IPTI (Inter PDU Transmission
Interval) information may be handed over as an addition.
[0315] IPTI information is information that prescribes the data
transmission spacing (period) of subflows, and by means of IPTI
information, voice data can be uniquely calculated from the total
data size of subflow and the AMR codec rate even when the transfer
of voice data is not carried out.
[0316] Although explanation has been presented that the present
invention can be applied to intra-HNB-GW relocation between HNB in
the first to sixth exemplary embodiments, the present invention may
also be applied to inter-HNB-GW relocation (relocation in which
HNB-S 2 and HNB-T 3 are not connected to the same HNB-GW).
[0317] In the fifth and sixth exemplary embodiments, HNB-T 3
included the RFCI information of HNB-T 3 in an Iu-UP Init message
and transmitted the message, but if the RFCI information of HNB-S 2
has been received at the time that the Iu-UP Init message is to be
transmitted, the transmission of the Iu-UP Init message by HNB-T 3
may be prohibited.
[0318] The method that is carried out in HNB-S, HNB-T, HNB-GW, and
CN node of the present invention may also be applied to a program
for causing execution by a computer. In addition, this program can
be stored on a recording medium and can be provided to the outside
by way of a network.
[0319] This application claims the benefits of priority based on
Japanese Patent Application No. 2009-187320 for which application
was submitted on Aug. 12, 2009 and incorporates by way of citation
all of the disclosures of that application.
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