WO2009128438A1

WO2009128438A1 - Radio base station and mobile station

Info

Publication number: WO2009128438A1
Application number: PCT/JP2009/057487
Authority: WO
Inventors: 幹生岩村
Original assignee: 株式会社エヌ・ティ・ティ・ドコモ
Priority date: 2008-04-17
Filing date: 2009-04-14
Publication date: 2009-10-22
Also published as: JP2009260749A; JP5162311B2

Abstract

Provided is a radio base station eNB including a transmission timing decision unit (11) which shifts a start position of a transmission window of other system information SI-n by a predetermined interval Y when a plurality of other system information SI-n are mapped for one radio frame.

Description

Radio base station and mobile station

The present invention provides a radio base station configured to transmit one first system information and one or more other system information to the mobile station, and one first system information from the radio base station. The present invention relates to a mobile station configured to receive one system information and one or more other system information.

In the LTE (Long Term Evolution) mobile communication system, as shown in FIG. 1, the radio base station eNB transmits a MIB (Master Information Block) to the mobile station UE by BCH (Broadcast Channel). A plurality of system information (System Information) is transmitted by DL-SCH (Downlink Shared Channel).

Here, a plurality of SIBs (System Information Blocks) 1-8 are mapped to the system information SI.

SIB1 includes information necessary for determining whether or not the mobile station UE can wait, such as a PLMN-ID and a cell ID, and is always mapped to first system information SI (System Information) -1.

On the other hand, SIB2 to SIB8 are grouped and mapped to other system information after SI-2.

The SIB is a message including specific information elements, and the SI may be considered as a container for carrying the SIB.

Also, the SIB1 mapped to the first system information SI-1 is configured to broadcast scheduling information of other system information after SI-2, so that the transmission cycle T of each SI is broadcasted. It is configured. Further, SIB1 is configured to broadcast SIB-to-SI mapping information.

In addition, the transmission cycle of the first system information SI-1 is fixed at 80 ms. However, it is possible to repeatedly transmit the first system information SI-1 within 80 ms.

On the other hand, the transmission cycle of other system information after SI-2 can be changed, and is assumed to be, for example, about 80 ms to 1.28 s.

The radio base station eNB is configured to transmit each system information in a radio frame having a frame number SFN where “SFN mod (T) = 0” is established. Here, “T” is a transmission cycle of each system information, and for SI-1, T = 80 ms.

The radio base station eNB is configured to transmit the first system information SI-1 using DL-SCH in the fifth subframe in the radio frame satisfying “SFN mod T = 0”.

Also, the radio base station eNB, based on the scheduling information included in the first system information SI-1 (SIB1), transmits a radio frame for transmission of other system information after SI-2 (in the example of FIG. 3, SFN = 0). The transmission subframe is determined in the radio frame).

Note that the radio base station eNB may be configured to repeatedly transmit each of the system information SI within the transmission window.

Here, in the conventional LTE mobile communication system, all subframes in each radio frame cannot be used for downlink data transmission, and transmission windows of SI-n (n = 2, 3,. There is a constraint that cannot be stacked. In addition, there is a restriction that a plurality of SI cannot be transmitted in the same subframe.

This is because SI is transmitted using DL-SCH, so the presence of SI data using the PDCCH (Physical Downlink Control Channel, L1 / L2 control channel), the location of the resource block where SI data is transmitted, etc. This is because only one ID (SI-RNTI, SI Radio Network Temporary Identity) to be notified on the PDCCH is specified in the system.

However, in the conventional LTE mobile communication system, when a plurality of SI-n is mapped to one radio frame, it is defined which subframe should be used to transmit the plurality of SI-n. Therefore, there is a problem in that both the radio base station eNB and the mobile station UE cannot determine subframes used for transmission of a plurality of SI-n.

Since the mobile station cannot determine which SI is specifically transmitted at which timing, in order to receive the specific SI that it needs, in all subframes where SI may be transmitted, There was a need to try to receive.

In addition, in a conventional LTE mobile communication system, “Semi-persistent resource allocation” can be applied assuming traffic such as VoIP.

Normally, when transmitting data on DL-SCH, it is necessary to notify the mobile station ID (C-RNTI, Cell specific RNTI) in PDCCH, and also notify the resource block position and transport block size. This is called “Dynamic scheduling”.

On the other hand, when “Semi-persistent resource allocation” is applied, a specific resource block can be periodically allocated to a specific mobile station at a specific period. By doing in this way, the overhead of PDCCH can be reduced. Such an allocation method may be referred to as “Persistent scheduling”.

When applying “Persistent scheduling”, it is necessary to be able to secure a specific resource block periodically (for example, a cycle in which VoIP packets are generated).

However, when the system information SI is transmitted, the resource block is occupied by the SI, and there is a problem that the resource block cannot be periodically secured.

In particular, when system information SI is transmitted in a concentrated manner in a specific radio frame, there is a problem that the number of resource blocks to which “Persistent scheduling” can be applied is significantly limited.

Therefore, the present invention has been made in view of the above-described problems, and when a plurality of SI-n is mapped to one radio frame in an LTE mobile communication system, the radio base station eNB and the mobile It is an object of the present invention to provide a mobile station and a radio base station that can determine subframes used for transmission of a plurality of SI-n in both stations UE.

Also, an object of the present invention is to provide a mobile station and a radio base station that can secure as many resource blocks as possible to which “Persistent scheduling” can be applied.

A first feature of the present invention is a radio base station configured to transmit one first system information and one or more other system information to a mobile station, The present invention includes a transmission timing determination unit configured to shift the start position of the transmission window of the other system information by a predetermined interval Y when a plurality of other system information is mapped to the radio frame. .

In the first feature of the present invention, when the transmission interval of the other system information is T, the transmission timing determination unit performs the other for a radio frame with a frame number SFN that satisfies “SFN mod T = 0”. It may be configured to map system information.

The second feature of the present invention is to transmit one first system information SI-1 and one or more other system information SI-n (n = 2, 3,...) To the mobile station. If the transmission interval of the other system information is T and the predetermined interval is Y, the frame number SFN that satisfies “SFN mod T = (n−2) × Y” is established. The gist is to include a transmission timing determination unit configured to map the other system information to a radio frame.

In the first and second features of the present invention, the predetermined interval Y may be a fixed value or a value notified by the first system information.

In the first and second aspects of the present invention, the predetermined interval Y is a time interval corresponding to the number of subframes that is an integral multiple of the number of subframes included in one radio frame, and the size of the transmission window. May be equal to or greater than the time interval corresponding to the number of subframes that can be used for transmission of downlink data corresponding to.

In the first and second features of the present invention, the subframe that can be used for transmitting the downlink data may not include a subframe that transmits the first system information.

In the first and second features of the present invention, the subframe that can be used for transmitting downlink data may not include a subframe that is used for transmitting uplink data in the TDD scheme.

In the first and second aspects of the present invention, the subframes usable for downlink data transmission include a subframe used for uplink data transmission and a subframe used for downlink data transmission in the TDD scheme. It is not necessary to include the special subframe provided between the two.

In the first and second features of the present invention, the subframe that can be used for transmitting downlink data may not include a subframe used for transmitting MBMS data (MBSFN subframe).

A third feature of the present invention is a mobile station configured to receive one first system information and one or more other system information from a radio base station, wherein the first system A reception timing determination unit configured to determine a reception radio frame and a reception subframe for the other system information based on the information, the reception timing determination unit for one radio frame When a plurality of other system information is mapped, the gist is that the start position of the transmission window of the other system information is shifted by a predetermined interval Y.

In the third aspect of the present invention, when the transmission interval of the other system information is T, the reception timing determination unit is configured to perform the other system for a radio frame having a frame number SFN that satisfies “SFN mod T = 0”. It may be configured to determine that the information is mapped.

According to a fourth aspect of the present invention, one first system information SI-1 and one or more other system information SI-n (n = 2, 3,...) Are received from a radio base station. A mobile station configured comprising: a reception timing determination unit configured to determine a reception radio frame and a reception subframe for the other system information based on the first system information; Assuming that the transmission interval of the other system information is T and the predetermined interval is Y, the reception timing determination unit performs the processing for the radio frame of the frame number SFN that satisfies “SFN mod T = (n−2) × Y”. The gist is that it is configured to determine that the other system information is mapped.

In the third and fourth aspects of the present invention, the predetermined interval Y may be a fixed value or a value notified by the first system information.

In the third and fourth aspects of the present invention, the predetermined interval Y is a time interval corresponding to the number of subframes that is an integral multiple of the number of subframes included in one radio frame, and the size of the transmission window. May be equal to or greater than the time interval corresponding to the number of subframes that can be used for transmission of downlink data corresponding to.

In the third and fourth aspects of the present invention, the subframe that can be used for transmitting the downlink data may not include a subframe for transmitting the first system information.

In the third and fourth aspects of the present invention, the subframe that can be used for transmitting downlink data may not include a subframe that is used for transmitting uplink data in the TDD scheme.

In the third and fourth aspects of the present invention, the subframes usable for downlink data transmission are subframes used for uplink data transmission in the TDD scheme and special subframes used for downlink data transmission. It is not necessary to include a special subframe provided between and.

In the third and fourth aspects of the present invention, the subframe that can be used for downlink data transmission may not include a subframe (MBSFN subframe) that is used for MBMS data transmission.

FIG. 1 is an overall configuration diagram of a mobile communication system according to a first embodiment of the present invention. FIG. 2 is a functional block diagram of the radio base station according to the first embodiment of the present invention. FIG. 3 is a diagram for explaining the System Information transmitted by the radio base station according to the first embodiment of the present invention. FIG. 4 is a diagram for explaining the System Information transmitted by the radio base station according to the first embodiment of the present invention. FIG. 5 is a functional block diagram of the mobile station according to the first embodiment of the present invention. FIG. 6 is a diagram for explaining System Information transmitted by the radio base station according to the second embodiment of the present invention. FIG. 7 is a diagram for explaining the System Information transmitted by the radio base station according to the third embodiment of the present invention. FIG. 8 is a diagram for explaining System Information transmitted by the radio base station according to the fourth embodiment of the present invention. FIG. 9 is a diagram for explaining System Information transmitted by the radio base station according to the fifth embodiment of the present invention. FIG. 10 is a diagram for explaining the System Information transmitted by the radio base station according to the sixth embodiment of the present invention. FIG. 11 is a diagram for explaining the System Information transmitted by the radio base station according to the seventh embodiment of the present invention. FIG. 12 is a diagram for explaining System Information transmitted by the radio base station according to the eighth embodiment of the present invention. FIG. 13 is a diagram for explaining System Information transmitted by the radio base station according to the ninth embodiment of the present invention. FIG. 14 is a diagram for explaining System Information transmitted by the radio base station according to the tenth embodiment of the present invention.

(Configuration of mobile communication system according to the first embodiment of the present invention)
The configuration of the mobile communication system according to the first embodiment of the present invention will be described with reference to FIGS. In the mobile communication system according to the present embodiment, it is assumed that the FDD scheme is applied (see FIGS. 3 and 4).

The mobile communication system according to the first embodiment of the present invention is an LTE mobile communication system. As shown in FIG. 1, the radio base station eNB transmits an MIB to the mobile station UE by BCH. However, it is configured to transmit a plurality of system information by DL-SCH.

Specifically, the radio base station eNB according to the present embodiment provides one first system information SI-1 (SIB1) and one or more other system information SI-2 to the mobile station UE. It is configured to transmit SI-5 (SIB2 to SIB8).

Here, four types of other system information SI-2 to SI-5 are assumed, but how many pieces of system information SI after SI-2 are used is an operational matter.

Also, how to map SIB2 to SIB8 to other system information after SI-2 is also an operational matter.

Furthermore, the SIB2 to SIB8 to be notified of which SIB is an operational matter, and it is not always necessary to notify all the SIBs. The operator may select the necessary number of SIBs and other system information according to the system operation mode.

As illustrated in FIG. 1, the radio base station eNB according to the present embodiment includes a transmission timing determination unit 11 and an SI transmission unit 12.

The transmission timing determination unit 11 determines a radio frame for transmission for the other system information SI-2 to SI-5 based on the transmission timing of the first system information SI-1, and is included in the first system information SI-1 Based on the scheduling information, it is configured to determine a transmission subframe in the determined transmission radio frame.

The transmission timing determination unit 11 sets the other system information for the radio frame having the frame number SFN where “SFN mod T = 0” is established, where T is the transmission interval of the other system information SI-2 to SI-5. It is configured to map SI-2 to SI-5.

Specifically, as shown in FIG. 3, when the transmission timing determination unit 11 maps a plurality of other system information SI-2 to SI-5 to one radio frame (SFN = 0), a predetermined interval is set. The start position of the transmission window of the other system information SI-2 to SI-5 is shifted by Y.

Here, the size of the transmission window of the other system information SI-2 to SI-5 may be a value notified by the first system information SI-1 (SIB1).

That is, as shown in FIG. 3, the transmission timing determination unit 11 sets “SFN mod T = (n−2)” where T is the transmission interval of the other system information SI-2 to SI-5 and Y is the predetermined interval. The other system information SI-2 to SI-5 is mapped to the radio frame having the frame number SFN in which “× Y” is established.

For example, in the example of FIG. 3, the transmission cycle T1 of the first system information SI-1 is “80 ms”, the transmission cycle T2 of the second system information SI-2 is “160 ms”, and the third system information SI− 3 is “320 ms”, the transmission cycle T4 of the fourth system information SI-4 is “640 ms”, and the transmission cycle T5 of the fifth system information SI-5 is “1280 ms”.

Here, the predetermined interval Y may be a fixed value or a value notified by the first system information SI-1 (SIB1).

Also, as shown in FIG. 4, the predetermined interval Y (Window start frame interval) is a time interval corresponding to the number of subframes that is an integral multiple of the number of subframes included in one radio frame.

For example, as shown in FIG. 4, when “predetermined interval Y (Window start frame interval) = 0”, the transmission timing determination unit 11 makes the transmission windows of the other system information SI-2 to SI-4 adjacent to each other. It is configured as follows.

Also, as shown in FIG. 4, when “predetermined interval Y (Window start frame interval) = 1”, the transmission timing determination unit 11 performs other system information SI-2 to SI-4 for one radio frame. The start position of the transmission window is shifted.

Furthermore, as shown in FIG. 4, when “predetermined interval Y (Window start frame interval) = 2”, the transmission timing determination unit 11 performs other system information SI-2 to SI-4 for two radio frames. The start position of the transmission window is shifted.

The SI transmission unit 12 is configured to transmit the other system information SI-2 to SI-5 in the transmission subframe determined by the transmission timing determination unit 11.

Also, the mobile station UE according to the present embodiment receives one first system information SI-1 and one or more other system information SI-2 to SI-5 from the radio base station eNB. It is configured.

As shown in FIG. 5, the mobile station UE according to the present embodiment includes a reception timing determination unit 21 and an SI reception unit 22.

The reception timing determination unit 21 is configured to determine a reception radio frame and a reception subframe for the other system information SI-2 to SI-5 based on the first system information SI-1.

Here, the reception timing determination unit 21 sets the other system information for the radio frame having the frame number SFN where “SFN mod T = 0” is satisfied, where T is the transmission interval of the other system information SI-2 to SI-5. It is configured to determine that SI-2 to SI-5 are mapped.

Specifically, as shown in FIG. 3, the reception timing determination unit 21 is predetermined when a plurality of other system information SI-2 to SI-5 is mapped to one radio frame (SFN = 0). The start position of the transmission window of the other system information SI-2 to SI-5 is shifted by an interval Y.

That is, as shown in FIG. 3, the reception timing determination unit 21 sets “SFN mod T = (n−2)” where T is the transmission interval of the other system information SI-2 to SI-5 and Y is the predetermined interval. It is configured to determine that the other system information SI-2 to SI-5 is mapped to the radio frame of the frame number SFN where “× Y” is established.

The SI receiving unit 22 is configured to receive the other system information SI-2 to SI-5 in the reception subframe determined by the reception timing determining unit 21.

Here, the predetermined interval Y can be set to a period for assigning resource blocks (for example, a 20 ms period in which a VoIP packet arrives) in “Persistent scheduling”. By doing in this way, it is possible to secure more resource blocks to which “Persistent scheduling” can be applied.

When performing “Persistent scheduling”, the cycle in which resource blocks are to be allocated may differ depending on the traffic.

For example, in the case of typical VoIP traffic, since a packet arrives once every 20 ms, it is efficient to allocate resource blocks periodically every 20 ms. In this case, the predetermined period Y may be 20 ms or an integer multiple of 20 ms.

Also, depending on the VoIP traffic, packets arrive at a 30 ms period or a 40 ms period. For example, when packet bundling is applied. In this case, the predetermined cycle Y may be 40 ms or an integer multiple of 40 ms.

On the other hand, when the predetermined period Y is set to “0”, the SI transmission windows are adjacent to each other. Since the transmission windows are adjacent, the mobile station can receive SIs in a shorter period of time when receiving all SIs. This is desirable for battery saving. When the amount of VoIP traffic is small, the predetermined period Y can be set to “0” to give priority to battery saving.

Thus, by making it possible to set the predetermined period Y, it is possible to balance the efficiency of “Persistent scheduling” and the battery saving. In the LTE system, the value of the predetermined cycle Y can be reported using SI-1 (SIB1).

(Operations and effects of the mobile communication system according to the first embodiment of the present invention)
According to the mobile communication system of the first embodiment of the present invention, even when a plurality of SI-n is mapped to one radio frame, all subframes in each radio frame are transmitted as downlink data. In consideration of the restriction that the transmission windows of each SI-n (n = 2, 3,...) Cannot be overlapped with each other in both the radio base station eNB and the mobile station UE. A subframe used for transmission of a plurality of SI-n's can be determined.

Further, more resource blocks to which “Persistent scheduling” can be applied can be secured, and the efficiency of “Persistent scheduling” and the battery saving can be balanced.

(Mobile communication system according to the second embodiment of the present invention)
With reference to FIG. 6, the mobile communication system according to the second embodiment of the present invention will be described by focusing on the differences from the mobile communication system according to the first embodiment described above.

As shown in FIG. 6, in the mobile communication system according to this embodiment, the predetermined interval Y (Window start frame interval) is a time interval corresponding to the number of subframes that is an integral multiple of the number of subframes included in one radio frame. And a time interval corresponding to the number of subframes that can be used for transmission of downlink data corresponding to the transmission window size of each of the other system information SI-2 to SI-4.

In the mobile communication system according to the present embodiment, the size of the transmission window of each other system information SI-2 to SI-4 is “5”. In such a case, it is assumed that the transmission window of each of the other system information SI-2 to SI-4 includes five subframes that can be used for downlink data transmission.

Here, in the LTE mobile communication system, there is a restriction that only one system information SI-1 to SI-5 can be transmitted in each subframe. Therefore, as shown in FIG. Subframe # 5 in which information SI-1 is transmitted is excluded from subframes that can be used for transmission of such downlink data.

In addition, the subframe that can be used for transmitting the downlink data may not include a subframe (MBSFN subframe) that is used for transmitting the MBMS data.

The MBSFN subframe is a subframe for applying the MBSFN transmission method that increases the reception power by transmitting the same data while synchronizing in a plurality of cells. This is because it cannot be transmitted.

For example, as illustrated in FIG. 6, in the case of “predetermined interval Y (Window start frame interval) = 0”, the transmission timing determination unit 11 determines the radio frame (SFN = 0) in accordance with the SI transmission window length. The first five subframes are reserved as a transmission window for other system information SI-2.

Further, since subframe # 5 in the radio frame (SFN = 0) is excluded from the subframes usable for transmission of the downlink data, the transmission window of other system information SI-3 is equivalent to 5 subframes + 1 subframe. The start position is shifted.

Further, as shown in FIG. 6, when “predetermined interval Y (Window start frame interval) = 2”, the transmission timing determination unit 11 performs other system information SI-2 to SI-4 for two radio frames. The start position of the transmission window is shifted.

Further, as shown in FIG. 6, when “predetermined interval Y (Window start frame interval) = 3”, the transmission timing determination unit 11 performs other system information SI-2 to SI-4 for three radio frames. The start position of the transmission window is shifted.

(Mobile communication system according to the third embodiment of the present invention)
With reference to FIG. 7, the mobile communication system according to the third embodiment of the present invention will be described while focusing on the differences from the mobile communication system according to the first embodiment described above.

As shown in FIG. 7, the mobile communication system according to the present embodiment is the same as the mobile communication system according to the first embodiment described above except that the TDD scheme is applied.

(Mobile communication system according to the fourth embodiment of the present invention)
With reference to FIG. 8, a mobile communication system according to a fourth embodiment of the present invention will be described focusing on differences from the mobile communication system according to the second embodiment described above.

In addition, as shown in FIG. 8, the TDD scheme is applied in the mobile communication system according to the present embodiment.

As shown in FIG. 8, in the mobile communication system according to the present embodiment, the predetermined interval Y (Window start frame interval) is a time interval corresponding to the number of subframes that is an integral multiple of the number of subframes included in one radio frame. And a time interval corresponding to the number of subframes that can be used for transmission of downlink data corresponding to the transmission window size of each of the other system information SI-2 to SI-4.

Here, the subframes that can be used for transmission of downlink data do not include the subframes that are used for transmission of uplink data (subframes # 2 to # 4 and # 7 to # 9 in the example of FIG. 8). May be.

In addition, a subframe that can be used for transmission of downlink data is a special subframe (see FIG. 5) provided between a subframe that is used for transmission of uplink data and a subframe that is used for transmission of downlink data in the TDD scheme. In the example of FIG. 8, subframes # 1 and # 6) may not be included.

The special subframe is a subframe provided with uplink and downlink guard intervals in the TDD scheme, and although it is for downlink transmission, the number of usable symbols is remarkably limited, and the number of symbols is too small to transmit SI. This is because there are cases.

In addition, the subframe that can be used for transmitting the downlink data may not include the subframe in which the first system information SI-1 is transmitted (subframe # 5 in the example of FIG. 8).

Furthermore, the subframe that can be used for transmitting the downlink data may not include a subframe (MBSFN subframe) that is used for transmitting the MBMS data.

(Mobile communication system according to the fifth embodiment of the present invention)
With reference to FIG. 9, a mobile communication system according to a fifth embodiment of the present invention will be described focusing on differences from the above-described mobile communication system according to the first embodiment.

In addition, as shown in FIG. 9, the FDD scheme is applied in the mobile communication system according to the present embodiment.

In the mobile communication system according to the present embodiment, as shown in FIG. 9, the transmission timing determination unit 11 maps a plurality of other system information SI-2 to SI-5 to one radio frame (SFN = 0). In this case, the transmission window start position of the other system information SI-2 to SI-5 is shifted by 5 subframes according to the SI transmission window length.

That is, the mobile communication system according to the present embodiment is configured such that the transmission windows of the other system information SI-2 to SI-5 are adjacent to each other.

(Mobile communication system according to the sixth embodiment of the present invention)
With reference to FIG. 10, a mobile communication system according to a sixth embodiment of the present invention will be described focusing on differences from the above-described mobile communication system according to the first embodiment.

As shown in FIG. 10, the FDD scheme is applied in the mobile communication system according to the present embodiment.

For example, as illustrated in FIG. 10, when “predetermined interval Y (Window start frame interval) = 0”, the transmission timing determination unit 11 determines whether the radio frame (SFN = 0) corresponds to the SI transmission window length. The first five subframes are reserved as a transmission window for other system information SI-2.

Also, since subframe # 5 in radio frame SFN = 0 is excluded from the subframes that can be used for transmission of the downlink data, the start of the transmission window of other system information SI-3 by 5 subframes + 1 subframe It is configured to shift the position.

That is, in the mobile communication system according to the present embodiment, as shown in FIG. 10, the predetermined interval Y (Window start frame interval) is a downlink corresponding to the size of the transmission window of each other system information SI-2 to SI-4. This is a time interval corresponding to the number of subframes that can be used for data transmission.

In the mobile communication system according to the present embodiment, as shown in FIG. 10, the predetermined interval Y (Window start frame interval) corresponds to the number of subframes that is an integral multiple of the number of subframes included in one radio frame. It may not be a time interval.

In the mobile communication system according to the present embodiment, the number corresponding to the size of the transmission window of each other system information SI-2 to SI-4 is included in the transmission window of each other system information SI-2 to SI-4. A subframe that can be used for transmission of downlink data may not be included.

(Mobile communication system according to the seventh embodiment of the present invention)
With reference to FIG. 11, the mobile communication system according to the sixth embodiment of the present invention will be described focusing on the differences from the mobile communication system according to the first embodiment described above.

As shown in FIG. 11, the FDD scheme is applied in the mobile communication system according to the present embodiment.

For example, as illustrated in FIG. 11, when “predetermined interval Y (Window start frame interval) = 0”, the transmission timing determination unit 11 determines whether the radio frame (SFN = 0) is in accordance with the SI transmission window length. The first five subframes are reserved as a transmission window for other system information SI-2.

That is, in the mobile communication system according to the present embodiment, as shown in FIG. 11, the predetermined interval Y (Window start frame interval) is a downlink corresponding to the size of the transmission window of each other system information SI-2 to SI-4. This is a time interval corresponding to the number of subframes that can be used for data transmission.

In the mobile communication system according to the present embodiment, as shown in FIG. 11, the predetermined interval Y (Window start frame interval) corresponds to the number of subframes that is an integral multiple of the number of subframes included in one radio frame. It may not be a time interval.

In the mobile communication system according to the present embodiment, the number corresponding to the size of the transmission window of each other system information SI-2 to SI-4 is included in the transmission window of each other system information SI-2 to SI-4. A subframe that can be used for transmission of downlink data is included.

(Mobile communication system according to the eighth embodiment of the present invention)
With reference to FIG. 12, a mobile communication system according to an eighth embodiment of the present invention will be described focusing on differences from the mobile communication system according to the fifth embodiment described above.

As shown in FIG. 12, the mobile communication system according to the present embodiment is the same as the mobile communication system according to the fifth embodiment described above except that the TDD scheme is applied.

(Mobile communication system according to the ninth embodiment of the present invention)
With reference to FIG. 13, the mobile communication system according to the ninth embodiment of the present invention will be described focusing on the differences from the mobile communication system according to the sixth embodiment described above.

As shown in FIG. 13, the mobile communication system according to the present embodiment is the same as the mobile communication system according to the sixth embodiment described above except that the TDD scheme is applied.

In the example of FIG. 13, in a radio frame with SFN = 0, subframe # 5 is used for transmission of SI-1, and cannot be used for transmission of other system information SI. Therefore, subframe # 5 is skipped and the SI-3 transmission window is started from subframe # 6.

In this way, at least one subframe always includes a subframe in which downlink data transmission is possible in the SI transmission window.

(Mobile communication system according to the tenth embodiment of the present invention)
With reference to FIG. 14, the mobile communication system according to the tenth embodiment of the present invention will be described focusing on the differences from the mobile communication system according to the seventh embodiment.

As shown in FIG. 14, the mobile communication system according to the present embodiment is the same as the mobile communication system according to the seventh embodiment described above except that the TDD scheme is applied.

In the example of FIG. 14, the SI transmission window always includes a predetermined number (5 in the example of FIG. 14) of subframes capable of transmitting downlink data. It is defined that an uplink transmission subframe, a special subframe, and a subframe in which SI-1 is transmitted are not included in a subframe in which downlink data can be transmitted.

In this way, a predetermined number of subframes can always be used for SI transmission, and retransmission of the same SI can be performed as many times as necessary within the SI transmission window.

(Example of change)
Note that the operations of the mobile station UE and the radio base station eNB described above may be implemented by hardware, may be implemented by a software module executed by a processor, or may be implemented by a combination of both. .

The software modules include RAM (Random Access Memory), flash memory, ROM (Read Only Memory), EPROM (Erasable Programmable ROM), EEPROM (Electronically Erasable and Programmable, Removable ROM, Hard Disk, and Removable ROM). Alternatively, it may be provided in a storage medium of an arbitrary format such as a CD-ROM.

Such a storage medium is connected to the processor so that the processor can read and write information from and to the storage medium. Further, such a storage medium may be integrated in the processor. Further, such a storage medium and a processor may be provided in the ASIC. Such an ASIC may be provided in the mobile station UE or the radio base station eNB. Further, the storage medium and the processor may be provided as a discrete component in the mobile station UE or the radio base station eNB.

As described above, the present invention has been described in detail using the above-described embodiments. However, it is obvious for those skilled in the art that the present invention is not limited to the embodiments described in the present specification. The present invention can be implemented as modified and changed modes without departing from the spirit and scope of the present invention defined by the description of the scope of claims. Therefore, the description of the present specification is for illustrative purposes and does not have any limiting meaning to the present invention.

Note that the entire content of Japanese Patent Application No. 2008-108390 (filed on April 17, 2008) is incorporated herein by reference.

As described above, according to the present invention, when a plurality of SI-n is mapped to one radio frame in the LTE mobile communication system, both the radio base station eNB and the mobile station UE It is possible to provide a mobile station and a radio base station that can determine a subframe used for transmission of such a plurality of SI-n.

Also, according to the present invention, it is possible to provide a mobile station and a radio base station that can secure as many resource blocks as possible to which “Persistent scheduling” can be applied.

Claims

A radio base station configured to transmit one first system information and one or more other system information to a mobile station,
A transmission timing determination unit configured to shift the start position of the transmission window of the other system information by a predetermined interval Y when a plurality of other system information is mapped to one radio frame; A wireless base station.
When the transmission interval of the other system information is T, the transmission timing determination unit is configured to map the other system information to a radio frame having a frame number SFN where “SFN mod T = 0” is established. The radio base station according to claim 1, wherein:
A radio base station configured to transmit one first system information SI-1 and one or more other system information SI-n (n = 2, 3,...) To the mobile station. There,
When the transmission interval of the other system information is T and the predetermined interval is Y, the other system information is mapped to the radio frame of the frame number SFN that satisfies “SFN mod T = (n−2) × Y”. A radio base station comprising a transmission timing determination unit configured to do
The radio base station according to any one of claims 1 to 3, wherein the predetermined interval Y is a fixed value or a value notified by the first system information.
The predetermined interval Y is a time interval corresponding to the number of subframes that is an integral multiple of the number of subframes included in one radio frame, and is a subspace that can be used for transmission of downlink data corresponding to the size of the transmission window. The radio base station according to any one of claims 1 to 3, wherein the radio base station is at least a time interval corresponding to the number of frames.
The radio base station according to claim 5, wherein a subframe that can be used for transmitting the downlink data does not include a subframe that transmits the first system information.
The radio base station according to claim 5, wherein the subframe usable for transmission of the downlink data does not include a subframe used for transmission of the uplink data in the TDD scheme.
The subframe usable for the downlink data transmission does not include a special subframe provided between the subframe used for uplink data transmission and the subframe used for downlink data transmission in the TDD scheme. The radio base station according to claim 5.
The radio base station according to claim 5, wherein the subframe that can be used for transmitting downlink data does not include a subframe (MBSFN subframe) that is used for transmitting MBMS data.
A mobile station configured to receive one first system information and one or more other system information from a radio base station,
A reception timing determination unit configured to determine a reception radio frame and a reception subframe for the other system information based on the first system information;
The reception timing determination unit is configured to shift the start position of the transmission window of the other system information by a predetermined interval Y when a plurality of other system information is mapped to one radio frame. A featured mobile station.
When the transmission interval of the other system information is T, the reception timing determination unit determines that the other system information is mapped to the radio frame having the frame number SFN in which “SFN mod T = 0” is established. The mobile station according to claim 10, configured as described above.
A mobile station configured to receive one first system information SI-1 and one or more other system information SI-n (n = 2, 3,...) From a radio base station. ,
A reception timing determination unit configured to determine a reception radio frame and a reception subframe for the other system information based on the first system information;
Assuming that the transmission interval of the other system information is T and the predetermined interval is Y, the reception timing determination unit determines that the radio frame with the frame number SFN that satisfies “SFN mod T = (n−2) × Y” is satisfied. A mobile station configured to determine that the other system information is mapped.
The mobile station according to any one of claims 10 to 12, wherein the predetermined interval Y is a fixed value or a value notified by the first system information.
The predetermined interval Y is a time interval corresponding to the number of subframes that is an integral multiple of the number of subframes included in one radio frame, and is a subspace that can be used for transmission of downlink data corresponding to the size of the transmission window. The mobile station according to any one of claims 10 to 12, wherein the mobile station has a time interval corresponding to the number of frames.
The mobile station according to claim 14, wherein a subframe that can be used for transmission of the downlink data does not include a subframe for transmitting the first system information.
The mobile station according to claim 14, wherein the subframe usable for downlink data transmission does not include a subframe used for uplink data transmission in the TDD scheme.
The subframe usable for the downlink data transmission does not include a special subframe provided between the subframe used for uplink data transmission and the subframe used for downlink data transmission in the TDD scheme. The mobile station according to claim 14.
The mobile station according to claim 14, wherein the subframe that can be used for transmitting downlink data does not include a subframe (MBSFN subframe) that is used for transmitting MBMS data.