JP2010041581A - Wireless communication system, communication method and base station - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wireless communication system for accommodating a plurality of kinds of terminals having different adaptive frequency bandwidths in a base station and effectively utilizing communication resources that the base station has. <P>SOLUTION: A radio frequency band of a base station is divided into a plurality of sub-bands each including a predetermined number of physical subcarriers, respectively. By applying a permutation pattern localized for each sub-band, the permutation of a modulation symbol is carried out between a logical subcarrier and a physical subcarrier. Thus, hop ports belonging to the same sub-band are mapped to physical subcarriers belonging to the same sub-band. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a radio communication system, and more particularly, to a cellular radio communication system adopting orthogonal frequency division multiple access (OFDMA), a communication method between a base station and a terminal, and a base station.

  As a user multiplexing method in a wireless communication system, there is orthogonal frequency division multiplexing (OFDMA). As shown in FIG. 1, an OFDMA cellular radio communication system includes a plurality of base stations (BS) 10 (10-1, 10-2,...) Connected to a base station controller (BSC) 20 by wired lines. .) And a plurality of terminals (AT: Access Terminal) 30 (30-1, 30-2,...) That communicate with each base station wirelessly. The base station control device 20 is connected to the network NW by a wired line. Each terminal 30 is wirelessly connected to the base station 10 located in the communication area, and communicates with other terminals, a server connected to the network NW, and other devices via the base station 10 and the base station control device 20. To do.

  In an OFDMA cellular radio communication system, it is necessary to assign a use subcarrier from a base station to a terminal prior to data transmission / reception between the terminal and the base station. The base station 10 enables simultaneous access by a plurality of terminals by allocating a group of subcarriers different from other terminals to each terminal from among a large number of subcarriers prepared in advance. Also, scalable bandwidth allocation is achieved by adjusting the number of allocated subcarriers for each terminal, and further, by selectively allocating subcarriers with good radio channel quality to each terminal, user diversity effects are achieved. It has gained.

  For example, in downlink data transmission from the base station 10 to the terminal 30, the base station 10 allocates a number of subcarriers corresponding to the amount of transmission data to each terminal. Control information (subcarrier allocation information) indicating the allocated subcarrier is notified to each terminal 30 via the control information channel in advance or in parallel with downlink data transmission. The base station 10 transmits downlink data using different subcarrier groups for each terminal. Each terminal 30 identifies a subcarrier group used for data transmission addressed to itself from the subcarrier allocation information received via the control information channel, and receives data addressed to itself by these subcarriers.

  On the other hand, in uplink data transmission from the terminal 30 to the base station 10, the terminal 30 transmits a data transmission request indicating a transmission data amount serving as requested bandwidth information to the base station 10 prior to data transmission. The base station 10 allocates a group of subcarriers to each terminal according to the transmission data amount indicated by the data transmission request, and notifies the subcarrier allocation information to the data transmission request source terminal through the control information channel.

  The terminal 30 specifies subcarrier groups to be used by the terminal from the subcarrier allocation information received from the base station 10, and transmits uplink data using these subcarriers. The base station 10 extracts uplink data of each terminal from subcarrier groups that differ for each terminal. As described above, in OFDMA, the base station and the terminal share the subcarrier allocation information, thereby realizing data transmission / reception.

  In the standardization organization 3GPP2, a wireless communication system using the above-described OFDMA is standardized as UMB (Ultra Mobile Broadband). The subcarrier allocation method in UMB is defined in Non-Patent Documents 1 to 7, for example.

  The IEEE 802.20 working group of the standardization organization IEEE has proposed a wireless communication system using the above-mentioned OFDMA as MBWA (Mobile Broadband Wireless Access). Non-patent documents 8 to 12 define the subcarrier allocation method in MBWA.

  In the standardization organization 3GPP, the above-described radio communication system using OFDMA is standardized as E-UTRA (Evolved Universal Terrestrial Radio Access) and E-UTRAN (Evolved Universal Terrestrial Radio Access Network). Non-patent documents 13 and 14 define the subcarrier allocation method in E-UTRA and E-UTRAN.

  In order to share the above-described subcarrier allocation information between the base station and each terminal, in UMB (Ultra Mobile Broadband), the base station notifies each terminal of downlink and uplink subcarrier allocation information. As the information blocks, FLAB (Forward Link Assignment Block) and RLAB (Reverse Link Assignment Block) are defined. FLAB and RLAB include scheduling information such as allocation subcarriers and allocation periods. In UMB, the concept of channel tree is used in order to efficiently notify the subcarrier allocation information from the base station to the terminal.

FIG. 2 shows a relationship between a channel tree 50 having a balanced binary tree structure and permutation executed between a logical subcarrier (hop port) and a physical subcarrier in the prior art.
Each node (node) of the channel tree 50 is assigned a serial number (“0” to “30” in FIG. 2) as a node ID in order from the root of the channel tree toward the leaves. Among the nodes included in the channel tree, the node corresponding to the leaf, that is, the node having the node ID = 15 to 30 in FIG. These base nodes are associated with a group of logical subcarriers (hop ports). Each base node is associated with a predetermined number of consecutive hop ports as indicated by block 51.

  The number Y of base nodes included in the channel tree is, as a general rule, a fast Fourier transform (FFT) size “N_FFT” used for OFDM modulation / demodulation, and the number of hop ports “N_BLOCK” per base node. And Y = “N_FFT” ÷ “N_BLOCK”. In UMB, “N_BLOCK” has a default value of 16, for example.

  The FFT size “N_FFT” is determined according to the frequency bandwidth of the wireless communication system. For example, N_FFT = 512 in a radio communication system with a base station frequency bandwidth of 5 MHz, and N_FFT = 1024 in a radio communication system with 10 MHz. In the following description, N_BLOCK consecutive hop ports are referred to as “hop port blocks”, and one hop port block is associated with one base node.

  The size of the channel tree 50 is uniquely determined by the number of base nodes. If the number of hop ports per base node (N_BLOCK) is set to a constant value, the size of the channel tree 50 is proportional to N_FFT or the frequency bandwidth of the base station. Information indicating the configuration of the channel tree is broadcast from the base station to all terminals through a broadcast channel called a preamble.

  The base station 10 assigns a subchannel corresponding to the requested bandwidth to each terminal by designating one or more base nodes for each terminal 30. Each terminal 30 transfers the modulation symbols on the hop port (logical subcarrier) block 51 corresponding to the base node designated by the base station 10 to the physical subcarrier 52 in a predetermined pattern. The mapping from the hop port (logical subcarrier) 51 to the physical subcarrier 52 and from the physical subcarrier 52 to the hop port is referred to as “permutation” 53.

  Typical permutation modes (frequency hopping modes) include BRCH (Block Resource Channel) and DRCH (Distributed Resource Channel). In the BRCH mode, consecutive N_BLOCK hop ports are mapped to consecutive N_BLOCK physical subcarriers, and m OFDM symbols and N_BLOCK physical subcarriers continuous on the time axis are defined as one block. Frequency hopping is performed.

  On the other hand, in the DRCH mode, consecutive N_BLOCK hop ports are mapped to N_BLOCK physical subcarriers dispersed at regular intervals throughout the frequency band, and frequency hopping is performed in units of k symbols. However, permutation combining the BRCH mode and the DRCH mode may be employed. Through permutation, each terminal can convert a group of hop ports designated by the base station with a base node ID into a group of physical subcarriers, and transmit and receive data (OFDM modulation symbols) on these physical subcarriers.

  If the base station and each terminal have the same channel tree configuration information and the same permutation pattern, the base station designates one node ID at a higher level than the base node on the channel tree. By simply doing this, it is possible to notify each terminal of the assigned subcarriers for a plurality of base nodes. In this case, each terminal determines that all base nodes subordinate to the designated node ID on the channel tree are assigned when the node ID is designated by the base station. The base station designates a lower-level node close to a leaf (base node) on the channel tree for a terminal with a small amount of transmission data, and an upper-level node close to the root for a terminal with a large amount of transmission data. By designating, it is possible to assign an amount of subcarriers corresponding to the requested bandwidth to each terminal.

  For example, when a base station notifies a terminal of node ID = 15, this terminal is assigned one hop port block corresponding to the base node having node ID = 15, that is, N_BLOCK subcarriers. It will be. When the base station notifies the terminal of node ID = 3, all base nodes subordinate to node ID = 3, that is, four base nodes of node ID = 15, 16, 17, 18 are assigned. Therefore, the terminal can use four hop port blocks (N_BLOCK × 4) corresponding to these base nodes.

3GPP2 C.S0084-002-0 Version 2.0 5.5.4.1.1 Procedures for the F-SCCH 3GPP2 C.S0084-002-0 Version 2.0 6.5.3 Forward Traffic Channel Addressing 3GPP2 C.S0084-002-0 Version 2.0 6.5.5 Active State 3GPP2 C.S0084-002-0 Version 2.0 6.5.6 Channel Trees 3GPP2 C.S0084-002-0 Version 2.0 8.5.3 Reverse Traffic Channel Addressing 3GPP2 C.S0084-002-0 Version 2.0 8.5.5 Active State 3GPP2 C.S0084-002-0 Version 2.0 8.5.9 Channel Trees IEEE802.20 C802.20-06-04 7.1.4.1 Channel trees IEEE802.20 C802.20-06-04 7.4.6.3.1 Access network requirements IEEE802.20 C802.20-06-04 7.4.6.3.2 Access terminal requirements IEEE802.20 C802.20-06-04 7.5.6.2 Forward traffic channel addressing IEEE802.20 C802.20-06-04 7.5.6.4 Active state 3GPP TS36.300 V8.3.0 4.2.1 Multiple Access 3GPP TS36.300 V8.3.0 5.1.3 Physical Downlink Control Channel

  In the subcarrier allocation method using the channel tree described above, the base station and all terminals need to share the same channel tree information and the same permutation pattern in advance. Since the size of the channel tree and the permutation pattern is determined by the frequency bandwidth used in the wireless communication system, each terminal assigns the assigned hop port to another terminal in response to the node ID notified from the base station. In order to permutate to different subcarriers, it is assumed that all terminals have the same adaptive frequency bandwidth as the base station.

  When multiplexing multiple types of terminals with different adaptable frequency bandwidths using OFDMA, the base station needs to construct or operate a channel tree according to the terminal with the narrowest adaptive frequency bandwidth among all terminals. There is. In this case, even if many terminals have the capability of adapting to a wide frequency band, the frequency band that can be operated in the base station is limited in accordance with the terminal having a narrow frequency bandwidth, resulting in a wide Waste is generated in the function of the terminal having the adaptive frequency bandwidth and the communication resource of the base station. In addition, the communication load may be concentrated on some physical subcarriers in the system frequency band.

  As one method for accommodating a plurality of types of terminals having different adaptive frequency bandwidths in the same base station, multi-carrier operation can be considered. In multi-carrier operation, the frequency band supported by the base station is divided into a plurality of carrier bands, and is operated separately for each carrier band. The carrier bandwidth is matched to the frequency bandwidth of the terminal having the narrowest adaptive frequency bandwidth among all terminals. In this case, in order to operate separately for each carrier band, it is necessary to configure separate channel trees for each carrier band. Therefore, it becomes difficult to distribute the load between the carrier bands, and there remains a problem that the load is concentrated on a part of the bands.

  It is an object of the present invention to accommodate a plurality of types of terminals having different adaptive frequency bandwidths in each base station, and to effectively use communication resources of the base station, communication between the base station and the terminal It is to provide a method and a base station.

  In order to achieve the above object, in the present invention, the radio frequency band of the base station is divided into a plurality of subbands each including a predetermined number of physical subcarriers, and a permutation pattern localized for each subband is obtained. Apply to perform modulation symbol permutation between logical and physical subcarriers. As a result, hop ports belonging to the same subband are mapped to physical subcarriers belonging to the same subband and are not distributed to physical subcarriers of different subbands.

  In the present invention, the base station applies a single channel tree composed of a plurality of local trees associated with the subbands described above and a global tree that integrates these local trees into a balanced binary tree structure. Subband allocation and subcarrier allocation to each terminal are performed.

A communication method between a base station and a terminal in an OFDMA cellular radio communication system according to the present invention is as follows:
The base station selecting one or a plurality of subbands applicable to the terminal from a plurality of subbands, and notifying the terminal as an assigned subband;
When the base station performs data communication with the terminal, and selects a group of subcarriers used for data communication within the range of the allocated subband, and notifies the terminal as the allocated subcarrier. ,
OFDMA data using the allocated subcarriers by the terminal and the base station performing modulation symbol transfer between logical subcarriers and physical subcarriers within the range of the allocated subbands. It is characterized by transmitting and receiving.

  The allocated subband is notified from the base station to the terminal, for example, in the downlink shared control channel of the OFDMA cellular radio communication system. The allocated subband may be notified to the terminal by a preamble transmitted through the broadcast information channel.

More specifically, the communication method according to the present invention includes:
The base station periodically broadcasting the radio frequency bandwidth of the base station and the number of subbands as broadcast information;
After the terminal receives the broadcast information, the terminal has a step of notifying the base station of the adaptive frequency bandwidth of the terminal,
The base station selects at least one subband to be allocated to the terminal according to the adaptive frequency bandwidth notified from the terminal, and notifies the terminal as the allocated subband.

  The broadcast information is broadcast from the base station by, for example, a preamble transmitted on a broadcast information channel of an OFDMA cellular radio communication system. In a preferred embodiment, the preamble is transmitted for each subband. The adaptive frequency bandwidth of the terminal is notified to the base station, for example, in the connection procedure to the base station executed by the terminal after receiving the broadcast information.

An OFDMA wireless communication system according to the present invention includes a base station that manages a wireless frequency band divided into a plurality of subbands each including a predetermined number of physical subcarriers, and at least one wirelessly connected to the base station. A device,
The base station
Subband management for selecting the number of subbands corresponding to the adaptive frequency bandwidth from the plurality of subbands and notifying the terminal as allocated subbands when notified of the adaptive frequency bandwidth from the terminal And
A link controller that selects a group of subcarriers to be used for data communication within the range of the allocated subbands and notifies the terminal as allocated subcarriers when performing data communication with the terminal;
Each of the above terminals
A first permutation unit that transfers modulation symbols on a plurality of physical subcarriers included in a signal received from the base station to a plurality of logical subcarriers; and a plurality of logics output from the first permutation unit A receiving unit including a demapping unit that converts modulation symbols on subcarriers into modulation symbols for each channel;
A mapping unit that maps modulation symbols of a plurality of channels to be transmitted to the base station to a plurality of logical subcarriers, and a modulation unit that transfers modulation symbols on the plurality of logical subcarriers output from the mapping unit to a plurality of physical carriers. A transmission unit including two permutation units;
A subband management unit for specifying a modulation symbol transfer range in the first permutation unit and the second permutation unit according to the assigned subband notified from the base station;
When data communication is performed with the base station, according to the assigned subcarrier notified from the base station, a logical subcarrier group from which the data modulation symbol is extracted in the demapping unit, and mapping of the data modulation symbol in the mapping unit A node designating unit that identifies a logical subcarrier group that is a destination is provided.

  Here, the 1st permutation part and the 2nd permutation part perform transfer of the modulation symbol for data between subcarriers according to the localized permutation pattern corresponding to the allocation subcarrier.

In addition, an OFDMA base station that communicates wirelessly with a plurality of terminals according to the present invention includes:
The radio frequency band is divided and managed into a plurality of subbands each including a predetermined number of physical subcarriers, and when the adaptive frequency bandwidth is notified from one of the plurality of terminals, the plurality of subbands A subband management unit that selects the number of subbands according to the adaptive frequency bandwidth from among them, and notifies the terminal as an assigned subband;
A link control unit for selecting a group of subcarriers used for data communication within the range of the allocated subbands and notifying the terminal as allocated subcarriers when performing data communication with the terminal;
A transmitter that maps a modulation symbol sequence generated from transmission data to the terminal to an assigned subcarrier selected by the link controller;
A receiving unit that extracts a modulation symbol sequence of a data channel received from the terminal from an assigned subcarrier selected by the link control unit;
The wireless transmission / reception circuit connected to the transmission unit and the reception unit is provided.

More specifically, the base station of the present invention is
A first permutation unit configured to transfer modulation symbols on a plurality of physical subcarriers included in a reception signal input from the radio transmission / reception circuit to a plurality of logical subcarriers; and the first permutation. A demapping unit for converting modulation symbols on a plurality of logical subcarriers output from the unit into modulation symbols for each channel,
The transmitter unit maps a plurality of channels of modulation symbols serving as transmission signals to a plurality of logical subcarriers, and transfers modulation symbols on the plurality of logical subcarriers output from the mapping unit to a plurality of physical carriers. Including a second permutation section to be replaced,
The modulation symbol transfer in the first permutation unit and the second permutation unit is performed according to a permutation pattern prepared for each subband.

  The mapping unit maps a modulation symbol serving as transmission data addressed to each terminal to a logical subcarrier according to the assigned subcarrier specified by the link control unit. The demapping unit extracts a modulation symbol serving as reception data addressed to each terminal from the logical subcarrier according to the assigned subcarrier specified by the link control unit.

  According to the present invention, even when there is a terminal having a narrow adaptive frequency bandwidth, it is not necessary to reduce the operation bandwidth at the base station, so that it is possible to operate the system with a wide frequency bandwidth. In addition, since the base station can distribute the load to a plurality of subbands, radio resources can be used effectively.

Hereinafter, a cellular radio communication system to which the present invention is applied will be described in detail with reference to the drawings.
FIG. 3 shows the relationship among the channel tree 50, the hop port 51, the physical subcarrier 52, and the permutation 53 applied to the OFDMA cellular radio communication system of the present invention.

  In the present invention, the channel tree 50 includes a plurality of local trees LT (LT0, LT1, LT2,...) And a global tree GT that bundles these local trees, and each base node in the channel tree 50 is As in the prior art described with reference to FIG. 2, each block is associated with one hop port block composed of N_BLOCK hop ports.

  Each local tree LT has the same size including a predetermined number (four in FIG. 3) of base nodes. When the number of local trees LT is M (M = 4 in FIG. 3), in the present invention, the hop port 51 is divided into M hop port subgroups 510, 511, 512,... Corresponding to the local tree LT. Divided. Here, each hop port subgroup includes four hop port blocks.

  In FIG. 3, in order to simplify the description, the number of ports (N_BLOCK) included in each hop port block is 8, and each hop port subgroup is configured by 32 (= 8 × 4) hop ports. The total number of physical subcarriers or hop ports included in the channel tree corresponds to the operating bandwidth of the base station, and here is 128 (= 32 × M).

  One feature of the present invention is that the physical subcarrier 52 band is divided into M subbands SB0, SB1, SB2,... As many as the hop port subgroup (510, 511, 512,...). , The permutation 53 is divided into M local permutations 530, 531, 532,... Corresponding to the local tree LT, and one subband and one local permutation for each hop port subgroup. Is associated with the station. The size of the subband may be adjusted to the frequency band of the terminal having the narrowest adaptive frequency band among a plurality of types of terminals accommodated in the base station 10.

  In the example shown in FIG. 3, the jth local permutation 53j (j = 0 to 3) hops all hop ports in the jth hop port subgroup 51j to physical carriers belonging to the jth subband SBj. Mapping is performed for each port block (in units of N_BLOCK). Hop ports belonging to the same hop port subgroup 51j are not distributed and mapped to different subbands.

  The local permutations 530, 531,... May have the same permutation pattern, but a combination of arrows displayed between the hop port 51 and the physical carrier 52 in FIG. As can be seen, each can have its own permutation pattern. Here, in order to simplify the control, the jth hop port subgroup 51j is associated with the jth subband SBj. For example, the hop port subgroup 510 is assigned to the subband SB1, and the hop port subgroup 511 is assigned to the jth hop port subgroup SBj. Permutation can also be executed by associating subband SB2,..., Hop port subgroup 513 with subband SB0.

  In the following description, for simplification, the permutation is limited to the BRCH (Block Resource Channel) mode, and 8 hop ports (hop port blocks) continuous in each hop port block correspond to the hop port block. Suppose that it is mapped to 8 consecutive physical subcarriers in the subband.

  In the present invention, as described above, the physical subcarrier 52 is divided into a plurality of subbands, and the hop port group is mapped from the hop port subgroup to the subband by local permutation. Therefore, it is necessary to notify each terminal of the definition information of the frequency bandwidth and the subband.

  The frequency bandwidth and subband definition information can be transmitted, for example, in a broadcast channel communication frame (preamble) received first when each terminal attempts to connect to the base station. Further, the base station transmits the preamble for each subband, so that a plurality of types of terminals having different adaptive frequency bandwidths can receive the frequency bandwidth and subband definition information.

  In the present invention, each terminal notifies the base station of an adaptable frequency bandwidth, and the base station determines one or a plurality of subbands to be used by the terminal according to the adaptive frequency bandwidth of the terminal. Decide and notify this to the terminal. Further, each time data is transmitted / received to / from the terminal, the base station selects a free subcarrier corresponding to the requested bandwidth within the range of the designated subband and notifies the terminal of it.

FIG. 4 shows an embodiment of a radio transmission / reception unit of the base station 10 of the present invention used in the OFDMA system cellular radio communication system shown in FIG.
The radio transmission / reception unit of the base station 10 includes a baseband transmission unit 11, a downlink control unit 12 for controlling data communication in the downlink, a baseband reception unit 13, and a data communication in the uplink. It comprises an uplink control unit 14, a subband management unit 15, a broadcast information generation unit 16, a radio transmission / reception circuit 17, and a transmission / reception antenna 19. The baseband transmission unit 11 and the baseband reception unit 13 are connected to the main control unit of the base station, which is omitted in the drawing, and the baseband transmission unit 11 converts the transmission data output from the main control unit into an OFDMA signal. The baseband reception unit 13 converts the OFDMA signal input from the radio transmission / reception circuit 17 into reception data and outputs the received data to the main control unit.

  The baseband transmission unit 11 performs a hybrid automatic repeat request (HARQ :) with respect to an encoding unit 112 (112-1 to 112-n) that performs error correction encoding of transmission data and an output signal from the encoding unit 112. A repetition unit 113 (113-1 to 113-n) that performs transmission codeword repetition processing (repetition) in Hybrid Automatic Repeat Request control, and a modulation unit 114 (114-1) for modulating the output signal of the repetition unit 113 114-n), a hop port mapping unit 115 for mapping the modulation symbols output from the modulation unit 114 (114-1 to 114-n) in parallel to the hop port, and the modulation symbol from the hop port. Permutation section 116 for transferring to carrier, and OFDM multicarrier for subcarrier signal Inverse Fast Fourier Transform (IFFT) unit 117 that performs modulation, and CP addition that adds CP (Cyclic Prefix) to the output of IFFT unit 117 in order to increase resistance to delayed arrival waves in the radio propagation path Part 118. As described with reference to FIG. 3, the permutation unit 116 stores a plurality of local permutation patterns corresponding to each subband, and the modulation of each hop port subgroup is performed according to these local permutation patterns. The symbol is transferred to the subband corresponding to the hop port subgroup.

  The baseband transmission unit 11 further includes a control information coding / modulation unit 119 that performs error correction coding and subcarrier modulation on the control information supplied from the downlink control unit 12 and the uplink control unit 14, and will be described later. A preamble encoding / modulating unit 110 that performs error correction encoding and subcarrier modulation on a preamble including broadcast information to be transmitted. The control channel modulation symbol sequence output from the control information encoding / modulation unit 119 and the broadcast channel modulation symbol sequence output from the preamble encoding / modulation unit 110 are input to the hop port mapping unit 115, and the modulation unit The data channel modulation symbol sequence output from 114 is mapped to the hop port.

  The downlink control unit 12 includes a retransmission control unit 121 that performs HARQ retransmission control in the downlink, a PF determination unit 122 that determines a packet format (PF) to be used in the downlink, and a FLAB that includes scheduling information in the downlink ( A FLAB generation unit 123 that generates a Forward Link Assignment Block) and a node assignment unit 124 that allocates a hop port to be used for each terminal are included.

  The baseband receiving unit 13 deletes a CP from a reception signal input from the radio transmission / reception circuit 17 and a fast Fourier transform (FFT) for demodulating an OFDM multicarrier from the output signal of the CP deleting unit 131. Transform) unit 132, permutation unit 133 that transfers the modulation symbol of the subcarrier output from FFT unit 132 to the hop port, and the modulation symbol is extracted from the hop port, and demodulation unit 135 (135-1 to 135- n) and a hop port demapping unit 134 that outputs to the control information demodulation / decoding unit 139. Permutation section 133 stores a plurality of local permutation patterns corresponding to each subband, and transfers the modulation symbols of each subband (physical carrier) to the hop port subgroup corresponding to the subband. .

  Demodulation section 135 (135-1 to 135-n) demodulates the modulation symbol output from hop port demapping section 134, and outputs the demodulated symbol to de repetition section 136 (136-1 to 136-n). The de-repetition unit 136 performs received codeword power addition processing (de-repetition) in HARQ retransmission control. The output of the de-repetition unit 136 is subjected to error correction decoding by a decoding unit 137 (137-1 to 137-n) and then subjected to error detection by a CRC (Cyclic Redundancy Check) check unit 138 (138-1 to 138-n). The received data is input to the main control unit. The control information demodulation / decoding unit 139 performs demodulation and error correction decoding of the modulation symbol for control information output from the hop port demapping unit 134.

  The uplink control unit 14 determines the decoding result of the CRC check unit 138 and generates an ACK / NAK generation unit 141 that generates ACK or NAK, a retransmission control unit 142 that performs HARQ retransmission control in the uplink, and an uplink. A PF determining unit 143 that determines a packet format (PF) to be used, an RLAB generating unit 144 that generates an RLAB (Reverse Link Assignment Block) including scheduling information in the uplink, and a node assigning unit that allocates a hop port to each terminal 145.

  The subband management unit 15 has a memory 18 for storing information such as the configuration information, subband definition information, permutation pattern, corresponding frequency band for each terminal and assigned subband of the channel tree 50 described in FIG. A sub-band and a hop port (node ID) are assigned to each terminal by program control.

  The broadcast information generation unit 16 generates a preamble including broadcast information such as control information and time synchronization information generated by the subband management unit 15 and outputs the preamble to the preamble encoding / modulation unit 110 of the baseband transmission unit 11. The radio transmission / reception circuit 17 converts the baseband OFDMA transmission signal output from the baseband transmission unit 11 into an RF (Radio Frequency) signal, amplifies the power, outputs the signal to the transmission / reception antenna 19, and receives it by the transmission / reception antenna 19. The converted RF signal is converted into a baseband OFDMA signal and output to the baseband receiver 13.

FIG. 5 shows an embodiment of a terminal 30 applied to the OFDMA wireless communication system shown in FIG.
The terminal 30 includes a baseband transmission unit 31, an uplink control unit 32 that controls data communication in the uplink, a baseband reception unit 33, a downlink control unit 34 that controls data communication in the downlink, and a subband. It comprises a management unit 35, a broadcast information acquisition unit 36, a radio transmission / reception circuit 37, a propagation path estimation unit 38, and a transmission / reception antenna 39.

The baseband transmission unit 31 and the baseband reception unit 33 are connected to a main control unit of a terminal not shown in the drawing, and the baseband transmission unit 31 converts transmission data output from the main control unit into an OFDMA signal The baseband reception unit 33 converts the OFDMA signal input from the wireless transmission / reception circuit 37 into reception data and outputs the received data to the main control unit.
The baseband transmission unit 31 includes an encoding unit 312 that performs error correction encoding of transmission data, a repetition unit 313 that performs repetition processing in HARQ retransmission control on an output signal from the encoding unit 312, and a repetition unit 313. A modulation unit 314 for modulating the output signal, a hop port mapping unit 315 for mapping the modulation symbol output from the modulation unit 314 to the hop port, and a permutation unit for transferring the modulation symbol from the hop port to the subcarrier 316, an IFFT unit 317 that performs OFDM multicarrier modulation on the subcarrier signal, and a CP adding unit 318 that adds a CP to the output signal of the IFFT unit 317 in order to increase resistance to delayed arrival waves in the radio propagation path, And a control information encoding / modulating unit 319.

  The control information encoding / modulating unit 319 performs error correction encoding and modulation on various control information input from the uplink control unit 32, the downlink control unit 34, and the subband management unit 35. The output signal of control information encoding / modulation section 319 is output to hop port mapping section 315 and mapped to the hop port together with the modulation symbol of the transmission data output from modulation section 314.

  The uplink control unit 32 controls uplink HARQ retransmission performed by the repetition unit 313 of the baseband transmission unit 31 according to the ACK / NAK signal output from the control information demodulation / decoding unit 339 of the baseband reception unit 33. Based on the PF signal output from the RLAB acquisition unit 321, the RLAB acquisition unit 322 that acquires RLAB that is scheduling information in the uplink from the control information demodulation / decoding unit 339 of the baseband reception unit 33, and the RLAB acquisition unit 322. A packet format (PF) to be used in the uplink, a PF determination unit 323 that controls the encoding unit 312 and the modulation unit 314 of the baseband transmission unit 31, and a node ID output from the RLAB acquisition unit 322 According to the signal, the assigned hop port is specified, and the baseband transmission unit 31 A node designation unit 324 that designates a hop port to be used in the uplink to the port mapping unit 315, and a power that can be output for uplink data transmission based on an output signal of the propagation path estimation unit 38; The control information encoding / modulating unit 319 of the baseband transmitting unit 31 includes a Delta determining unit 325 that outputs Delta indicating output power.

  The baseband receiving unit 33 includes a CP deleting unit 331 that deletes a CP from the received signal input from the wireless transmission / reception circuit 37, an FFT unit 332 that demodulates an OFDM multicarrier from the output signal of the CP deleting unit 331, and an FFT unit 332 Permutation unit 333 for transferring modulation symbols output from subcarriers to hop ports, hop port demapping unit 334 for extracting modulation symbols from hop ports, and data channel output from hop port demapping unit 334 A demodulating unit 335 that demodulates the modulation symbol, a de repetition unit 336 that performs de-duplication in HARQ retransmission control on the output signal of the demodulating unit 335, and a decoding unit 337 that performs error correction decoding on the output signal of the de-repetition unit 336, , Decoding result of decoding unit 337 And a CRC check unit 338 for detecting the Luo error. The reception data output from the CRC check unit 338 is input to the main control unit of the terminal.

  The baseband receiving unit 33 further includes a control information demodulation / decoding unit 339 that performs demodulation and error correction decoding on the modulation symbol of the control information channel output from the hop port demapping unit 334, and a hop port demapping unit 334. The preamble demodulating / decoding unit 330 performs demodulation and error correction decoding on the modulation symbols of the preamble output from the.

  The downlink control unit 34 generates an ACK signal or a NAK signal according to the decoding result in the CRC check unit 338 of the baseband receiving unit 33, and outputs the ACK signal to the control information encoding / modulating unit 319 of the baseband transmitting unit 31. / NAK generation unit 341, retransmission control unit 342 that performs HARQ retransmission control in the downlink according to the ACK / NAK signal generated by ACK / NAK generation unit 341, and the control information demodulation / decoding unit 339 of baseband reception unit 33 Baseband reception by determining a packet format (PF) to be used in the downlink based on the PF signal output from the FLAB acquisition unit 343 that acquires FLAB including downlink scheduling information from PF determining unit for controlling demodulating unit 335 and decoding unit 337 of unit 33 44 and a node designation unit 345 that specifies an assigned hop port from the node ID signal output from the FLAB acquisition unit 343 and designates the hop port used in the downlink to the hop port demapping unit 334 of the baseband reception unit 33. CQI (Channel Quality Indicator) indicating the radio channel quality to the control information encoding / modulating unit 319 of the baseband transmitter 31 based on the output signal of the channel estimator 38. ) To output a CQI determination unit 346.

  The subband management unit 35 is configured by a processor including a memory 380 for storing channel tree configuration information, permutation patterns, subband definition information, frequency bands to which the terminal can adapt, allocated subband information, and the like. .

  In this embodiment, the permutation unit 316 of the baseband transmission unit 31 stores a plurality of local permutation patterns corresponding to each subband, and the subband ID is used from the subband management unit 35 as a subband ID. When a carrier band is designated, local permutation of modulation symbols is executed between the subband specified by the subband ID and the hop port subgroup. When the adaptive frequency band of the terminal 30 is wide, a plurality of subbands are designated as used subcarrier bands.

  Similar to the permutation unit 316, the permutation unit 333 of the baseband receiving unit 33 also stores a plurality of local permutation patterns corresponding to each subband. When the subcarrier band to be used is specified by the ID, local permutation of the modulation symbol is executed between the subband specified by the subband ID and the hop port subgroup.

  The broadcast information acquisition unit 36 acquires broadcast information such as system information, subband definition information, and time synchronization information from the preamble signal output by the preamble demodulation / decoding unit 330 of the baseband reception unit 33, and the subband management unit 35. Output to.

  The radio transmission / reception circuit 37 converts the baseband OFDMA transmission signal output from the baseband transmission unit 31 into an RF (Radio Frequency) signal, amplifies the power, outputs the amplified signal to the transmission / reception antenna 39, and receives it by the transmission / reception antenna 39. The converted RF signal is converted into a baseband OFDMA signal and output to the baseband receiver 33.

FIG. 6 shows the contents of the memory 18 referred to by the subband management unit 15 of the base station 10.
In the memory 18, a channel tree configuration information table 180, a subband management table 190, a terminal management table 200, and other tables are formed.

  For example, as schematically shown in FIG. 7, the channel tree configuration information table 180 includes a node ID 181, a status 182, a logical subcarrier (hop port block ID) 183, a subband ID 184, and the number of terminals 185. The correspondence is shown.

  The node ID 181 includes a node ID portion 181A of the global tree and a node ID portion 181B of the local tree. In the node ID portions 181A and 181B, as indicated by L0 to L4, node ID values are stored hierarchically in order of node level. The status 182 indicates whether or not the base node having the lowest level node ID (“15” to “30” in FIG. 7) in the channel tree is idle in each of the uplink and the downlink.

  The logical subcarrier 183 indicates a hop port block ID (identification number) corresponding to the base node, and the subband ID 184 indicates an ID of a subband corresponding to the hop port block ID, for example, a subband number. The number of terminals 185 indicates the number of terminals to which a subband having a subband ID 184 has been assigned as subcarriers corresponding to the adaptable frequency band of the terminal.

  The channel tree configuration information table 180 illustrated here corresponds to the channel tree 50, hop port 51, and physical subcarrier 52 shown in FIG. 3, and one subband block ID corresponds to four base nodes. is doing. The subband management unit 15 of the base station 10 refers to the number of terminals 185 when assigning the used subband to each terminal 30, and corresponds to the adaptable frequency band of the terminal so that the number of terminals 185 is as uniform as possible. Search for a number of subbands. A plurality of subbands having consecutive subband IDs are allocated to a terminal having an adaptable frequency band for a plurality of subbands. The number of terminals 185 increases due to terminal connection (subband allocation) to the base station, and decreases due to terminal disconnection (subband release).

  In a preferred embodiment of the present invention, the hop port mapping unit 115 and the hop port demapping unit 134 of the base station, and the hop port mapping unit 315 and the hop port demapping unit 334 of each terminal 30 are included in the channel tree configuration information table 180. The relationship between the node ID 181 and the logical subcarrier (hop port block ID) 183 is stored as channel tree information. According to this configuration, the hop port mapping unit and the hop port demapping unit convert the upper node ID to a plurality of base node IDs by themselves when the upper node ID is specified by the node assigning unit or the node specifying unit. Thus, it is possible to specify a hop port group from which a modulation symbol is to be output or a hop port group from which a modulation symbol is to be extracted.

FIG. 8 shows a configuration example of the subband management table 190.
The subband management table 190 is a plurality of tables showing the correspondence between the subband ID 191, the physical subcarrier 192 included in the subband having the subband ID 191, and the local permutation pattern 193 to be used in each subband. Consists of entries. However, the entity of the local permutation pattern 193 may be stored in another area of the memory 18, and the local permutation ID corresponding to the subband ID 191 may be stored in the subband management table 190.

FIG. 9 shows a configuration example of the terminal management table 200.
The terminal management table 200 includes a plurality of table entries having a terminal ID 201. Each table entry indicates the adaptive frequency bandwidth 202, the assigned subband 203, and the assigned node ID 204 of the terminal having the terminal ID 201. In the adaptive frequency band 202, the number of subbands corresponding to the adaptive frequency bandwidth of each terminal is stored. The assigned subband 203 and assigned node ID 204 store the subband ID and node ID assigned to each terminal by the subband management unit 15 of the base station 30. In the following embodiment, the subband number (0, 1, 2, 3,...) Is used as the subband ID 203, but the node ID of the channel tree may be used to reduce the amount of information. .

  As will be described later, the subband management unit 15 of the base station 10 selects one or more subbands corresponding to the adaptive frequency bandwidth notified from the terminal 30 when connecting the new terminal 30 to the base station. The assigned subband ID is notified to the terminal 30 and stored in the terminal management table 200 as the assigned subband 203.

  Each time data communication is performed with the terminal 30 thereafter, the subband management unit 15 sets the status 182 from the channel tree information table 180 to a free state in the node ID group corresponding to the assigned subband 203. A certain node ID is searched. When a frequency band required for data communication (hereinafter referred to as a request band) is sufficient in one hop port block, the subband management unit 15 performs a level L4 node ID (base node ID) corresponding to an empty base node. By designating, it is possible to assign a subcarrier for data communication to a terminal.

  When the requested bandwidth corresponds to a plurality of hop port blocks, the subband management unit 15 designates a higher-level node ID that becomes the apex of a plurality of continuous empty base nodes. For example, when the requested bandwidth corresponds to two hop port blocks, a node ID of level L3 is designated, and when it corresponds to four hop port blocks, a node ID of level L2 is designated. The status 182 of the base node that has been assigned to the terminal is rewritten from a free state to a used state, and is rewritten to a free state at the end of data transmission / reception.

FIG. 10 shows the contents of the memory 380 managed by the subband management unit 35 of each terminal 30.
In the memory 380, for example, the adaptive frequency bandwidth 381 of the terminal, channel tree configuration information 382, permutation pattern table 383, allocation subband ID (uplink / downlink) 384, allocation node ID (uplink / downlink) 385 , Subband size 386 and other information 387 are stored. The contents of the memory 380 are also referred to by the node designation unit 324 of the uplink control unit 32 and the node designation unit 345 of the downlink control unit 34.

FIG. 11 shows a communication sequence of subband information executed between the base station 10 and the terminal 30 prior to data communication in the OFDMA wireless communication system of the present invention.
The subband management unit 15 of the base station 10 divides the radio frequency band (band of the physical subcarrier 52) into a plurality of subbands (SB0, SB1, SB2,...) When the operation of the base station 10 is started. The size (bandwidth) of the subband is the bandwidth of the terminal with the narrowest adaptive frequency band among a plurality of types of terminals supported by the system. However, the size of the subband may be a fixed value set in advance in each base station according to the operation policy of the radio communication system, or may vary depending on the situation of the terminal accommodated in the base station during operation of the radio communication system. Anyway. In the latter case, the subband size is optimized according to the adaptable frequency bandwidth of the terminal that each terminal notifies to the base station when connecting to the base station.

  The base station 10 transmits the frequency bandwidth (N_FFT) used by the base station and the subband definition information to the terminal 30 using the preamble for transmitting the broadcast information to the terminal 30 (SQ01). The preamble is a signal of a common channel periodically transmitted from the base station in order to notify the terminal of setting information of the wireless communication system and each base station, and is received by all terminals located within the communication range of the base station 10 Is done. The format of the preamble will be described in detail later with reference to FIG.

  In this embodiment, it is assumed that the preamble is transmitted for each subband (SB0, SB1, SB2,...) Described in FIG. Further, the number M of subbands formed within the frequency bandwidth (N_FFT) is used as the subband definition information. In this case, each terminal can calculate the subband size from the frequency bandwidth (N_FFT) and the number N of subbands.

  The terminal 30 stores the frequency bandwidth notified from the base station and the calculated subband size in the memory 380, and stores the memory in advance in the initial parameter exchange (Configuration) executed at the start of data communication with the base station. The adaptive frequency bandwidth of the terminal stored in 380 is notified to the base station (SQ02). However, the notification of the adaptive frequency bandwidth from each terminal to the base station may be performed by another dedicated uplink control channel independent of the initial parameter exchange. In this embodiment, the adaptive frequency bandwidth notified from the terminal 30 to the base station 10 is represented by the number of subbands that can be permutated.

  The base station 10 stores the adaptive frequency bandwidth notified from the terminal in the terminal management table as the adaptive frequency bandwidth 202, and determines the subband 203 to be used by each terminal according to the adaptive frequency bandwidth. Then, this is notified to the terminal (SQ03). The subband to be used in the terminal is designated by the subband number, and is notified to each terminal 30 through, for example, a downlink control channel F-SCCH (Forward Link Shared Control Channel). When the terminal 30 has an adaptive frequency bandwidth corresponding to a plurality of subbands, the subband to be used in this terminal is designated by a plurality of consecutive subband numbers. The subband to be used in the terminal can be specified by a node ID on the channel tree instead of the subband number.

Hereinafter, the operations of the base station 10 and the terminal 30 in the sequences SQ01 to SQ03 will be specifically described with reference to FIGS.
In sequence SQ01, the subband management unit 15 of the base station 10 transmits the radio frequency bandwidth and the subband definition information in the base station to the broadcast information generation unit 16 illustrated in FIG. These pieces of information are passed to the preamble encoding / modulating unit 110 of the baseband transmitting unit 11 by the broadcast information generating unit 16. Preamble coding / modulation section 110 performs error correction coding and modulation processing on the preamble signal including the frequency bandwidth and subband definition information, and then outputs it to hop port mapping section 115 as a preamble modulation symbol sequence for each subband. To do.

  The modulation symbol sequence of the preamble is mapped to each hop port subgroup by the hop port mapping section 115 and then transferred to each subband by the permutation section 116. Subband preamble modulation symbols are subjected to inverse fast Fourier transform by IFFT section 117 and then input to CP adding section 118. The preamble signal to which the CP is added by the CP adding unit 118 is transmitted from the antenna 19 after undergoing conversion (up-conversion) and power amplification into an RF signal by the radio transmission / reception circuit 17.

  The preamble signal is received by the antenna 39 of the terminal 30, down-converted to a baseband signal by the radio transmission / reception circuit 37, then the CP symbol is deleted by the CP deletion unit 331, Fourier transformed by the FFT unit 382, and subjected to permutation. The data is input to the station 333. Permutation section 333 moves the preamble modulation symbol included in the subcarrier to the hop port and outputs it to hop port demapping section 334. In the case of a terminal having the narrowest adaptive frequency band, permutation section 333 transfers a receivable preamble of one subband to one hop port subgroup. In the case of a terminal having a wide adaptive frequency band, permutation section 333 moves the preamble to the corresponding hop port subgroup in a plurality of receivable subbands.

  The hop port demapping unit 334 outputs the preamble modulation symbol received in the specific hop port subgroup to the preamble demodulation / decoding unit 330. Preamble demodulation / decoding section 330 demodulates the preamble modulation symbol, performs error correction decoding, and outputs broadcast information extracted from the preamble to broadcast information acquisition section 36. The broadcast information acquisition unit 36 extracts the frequency bandwidth of the base station and the subband definition information (number of subbands) from the received broadcast information and passes the extracted information to the subband management unit 35.

FIG. 12 shows an example of a format of a preamble transmitted from the base station 10 to each terminal 30.
The length of the preamble is 8 OFDM symbols. Here, the period of symbol number 0 is F-PBCCH (Forward Link Primary Broadcast Channel) 41, the period of symbol numbers 1 to 4 is F-SBCCH (Forward Link Secondary Broadcast Channel) 42, and the period of symbol number 5 is TDM (Time (Division Multiplexing) 1 channel 43, the period of symbol number 6 is TDM2 channel 44, and the period of symbol number 7 is TDM3 channel 45.

  In the TDM1 channel 43, a parameter such as an N_FFT size indicating a frequency bandwidth and a parameter such as a CP length related to OFDM are transmitted. In the TDM2 channel 44, the base station ID is transmitted, and in the TDM3 channel 45, information regarding synchronization between base stations and information regarding the preamble transmission band are transmitted. In F-PBCCH 41, an information block (SystemInfo block) including parameters common to base stations is transmitted, and in F-SBCCH 42, an information block including parameters specific to each base station is transmitted. The subband definition information is transmitted as part of the SystemInfo block by F-PBCCH41.

  FIG. 13 shows an example of the format of the SystemInfo block 410 transmitted on the F-PBCCH 41 of the preamble. The SystemInfo block 410 includes fields 4101 to 4111.

IPSI (Initial Protocol Set Identifier) fields 4101 to 4104 are used to set a virtual route between the base station radio protocol and the terminal radio protocol. The SystemTimeLSB field 4105 indicates time information held by the base station, the TotalNumSubcarriers field 4106 indicates the total number of subcarriers, and the NumGuardSubcarriers field 4107 indicates the number of guard subcarriers. A NumShortChannelID field 4108 indicates related information of a beacon transmitted based on a frequency operation policy.
The FLReservedInterlaces field 4109 represents a time slot reserved for broadcast / multicast service, and the NumFLReservedSubzones field 4110 represents a frequency slot reserved for broadcast / multicast service. A NumSubbandPartitions field 4111 represents subband definition information (in this embodiment, the number of subbands).

The base station notifies each terminal of subband definition information, for example, the number of subbands, in a NumSubbandPartitions field 4111 included in the F-PBCCH of the preamble.
The broadcast information acquisition unit 36 of the terminal 30 passes to the subband management unit 35 the N_FFT received by the TDM1 channel 43 and the number of subbands received by the F-PBCCH 41 among the broadcast information received by the preamble. The subband management unit 35 calculates the size of the subband (number of subcarriers) by dividing N_FFT by the number of subbands, and stores it in the memory 380 as the subband size 386.

  The subband management unit 35 of the terminal 30 controls the adaptive frequency bandwidth 381 read from the memory 380 in the initial parameter exchange procedure (sequence SQ02) performed at the start of communication with the base station 10 as a control information encoding / modulating unit. To 319. The adaptive frequency bandwidth is subjected to error correction encoding and modulation processing by the control information encoding / modulating section 319, mapped to a predetermined hop port by the hop port mapping section 315, and converted to a subcarrier by the permutation section 316. It is transferred. The adaptive frequency bandwidth information on the subcarrier is subjected to OFDM multicarrier modulation by the IFFT unit 317, added with a CP by the CP adding unit 318, and then output to the radio transmission / reception circuit 37 as an OFDM signal. Sent.

  A transmission signal from the terminal 30 is received by the antenna 19 of the base station 10, converted into a baseband OFDM signal by the radio transmission / reception circuit 17, and then input to the CP deletion unit 139 of the baseband reception unit 13. The received modulation symbol is deleted by the CP deletion section 139, fast Fourier transformed by the FFT section 132, transferred from the physical subcarrier to the hop port by the permutation section 133, and then transferred to the hop port demapping section 134. Entered. The hop port demapping 134 outputs the modulation symbols for control information to the control information demodulation / decoding section 139 and the modulation symbols for user data to the demodulation sections 135 (135-1 to 135-n) among the received modulation symbols. .

  The control information demodulating / decoding unit 139 demodulates and error-correction-decodes the modulation symbol input from the hop port demapping 134, then analyzes the reception control information, and in accordance with the control information, as shown in FIG. The retransmission control unit 121, the PF determination unit 122 of the link control unit 12, the PF determination unit 143 of the uplink control unit 14, and the node assignment unit 145 are controlled. The adaptive frequency bandwidth received from the terminal 30 is passed from the control information demodulation / decoding unit 139 to the subband management unit 15 together with the terminal ID.

  Upon receiving the terminal ID and the adaptive frequency bandwidth of the terminal 30, the subband management unit 15 adds a new table entry indicating the new terminal ID 201 and the adaptive frequency bandwidth 202 to the terminal management table 200 of the memory 18. Then, referring to the number of terminals 185 in the channel tree configuration information table 180, the subband ID (subband number) corresponding to the adaptive frequency bandwidth of the terminal 30 is selected, and the corresponding number of terminals 185 is updated.

  The subband ID selected by the subband management unit 15 is, for example, notified to the terminal 30 as the subband information shown in the sequence SQ03 of FIG. 11 in the downlink shared control channel F-SCCH (Forward Link Shared Control Channel). The

  More specifically, the subband ID (subband number) selected by the subband management unit 15 is input to the control information encoding / modulating unit 119 of the baseband transmission unit 11. The control information encoding / modulating unit 119 includes a FLAB (Forward Link Assignment Block) generated by the FLAB generating unit 123 of the downlink control unit 12 and an RLAB (Reverse Link) generated by the RLAB generating unit 144 of the uplink control unit 14. Assignment Block), F-SCCH for transmitting the ACK / NAK signal generated by the ACK / NAK generation unit 141 is generated.

  The subband ID selected by the subband management unit 15 is subjected to error correction coding and modulation processing as part of control information transmitted on the F-SCCH in the control information coding / modulation unit 119, and the downlink common control signal Is input to the hop port mapping unit 115 as a modulation symbol. The modulation symbol of F-SCCH is mapped to a predetermined hop port by hop port mapping section 115 and transferred to a subcarrier by permutation section 116, and then converted into an OFDM signal format by IFFT section 117 and CP adding section 118. The converted signal is converted into an RF signal by the wireless transmission / reception circuit 17 and transmitted from the antenna 19 to the terminal 30.

  A control signal transmitted from the base station on the F-SCCH is received by the antenna 37 of the terminal 30 and is input from the wireless transmission / reception circuit 37 to the baseband reception unit 33. The control signal is input to the hop port demapping unit 334 via the CP deleting unit 331, the FFT unit 332, and the permutation unit 333 of the baseband receiving unit 33. The hop port demapping unit 334 outputs the modulation symbol for the control signal received on the F-SCCH to the control information demodulation / decoding unit 339.

  The control information demodulating / decoding unit 339 demodulates and error-correction-decodes the modulation symbol received from the hop port demapping unit 334, analyzes the received control information, and the RLAB is sent to the RLAB acquisition unit 322 of the uplink control unit 32. The ACK / NAK signal is output to the retransmission control unit 321 of the uplink control unit 32, the FLAB is output to the FLAB acquisition unit 343 of the downlink control unit 34, and the subband information is output to the subband management unit 35. The subband management unit 35 assigns the subband ID (subband number) received as subband information from the base station 10 to the memory 380 and stores it as the subband ID 384 and notifies the permutation units 316 and 333 of this. .

  Here, the base station 10 notifies the terminal 30 of the subband ID using the downlink control channel F-SCCH, but the subband ID uses the F-PBCCH 41 of the preamble as in the notification of the subband definition information. May be sent. Further, when the subband ID is notified to each terminal using the preamble, the F-SBCCH 42 may be used instead of the F-PBCCH 41. When the subband ID is notified using the preamble, a new field may be added to the SystemInfo block of FIG. 13 or the SubbandIndication field 4216 of the QuickChannelInfo block of FIG. 14 may be used. However, since the preamble is for reporting the same information to all terminals, when the subband ID is notified by the preamble, for example, the subband ID is uniquely set according to the adaptive frequency bandwidth of the terminal 30. Use a method such as specifying.

  FIG. 14 shows the format of a QuickChannelInfo block 420 transmitted on the F-SBCCH 42. The QuickChannelInfo block 420 includes a plurality of fields 4201 to 4216.

  In the CPICHHoppingMode field 4201 and the CommonPilotSpacing field 4214, information on the reference signal (pilot) transmission method is transmitted. In the NumEffectiveAntennas field 4202 and the FLNumSDMADimensions field 4212, information related to a communication speed improvement function using spatial processing such as MIMO (Multiple-Input Multiple-Output) and SDMA (Space Division Multiple Access) is transmitted.

In the FLSubzoneSize field 4203, the ResourceChannelMuxMode field 4204, the NumDRCHSubzones field 4205, and the BRCHSubzoneCyclingEnabled field 4206, information related to the hop port mapping method and the subcarrier permutation method is transmitted. In the UseDRCHforFLCS field 4207, the NumCommonSegmentHopPortBlock field 4208, the NumLABSegments field 4209, the MinSCCHResourceIndex field 4210, and the ModSymbolsPerQPSKLAB field 4213, information on the downlink control channel F-SCCH is transmitted. In the SinglePAForMultipleChannelBand field 4211, information related to transmission of a beacon signal is transmitted, and in the EnableExpandedQPCH field 4215, information related to terminal calling (paging) is transmitted.
The subband ID can be transmitted in the SubbandIndication field 4216.

Here, the initial connection operation with the base station performed by the terminal 30 will be briefly described.
The terminal 30 searches for the preamble transmitted by each base station 10 in order to select the base station 10 to be connected. If the preamble search is successful, the terminal 30 secures synchronization with the preamble and acquires system information. Note that the terminal 30 may start communication with the base station using a single subband corresponding to the first detected preamble.

  The terminal 30 connected to the base station receives the assigned subband ID from the base station through the F-SCCH and the preamble described above, and transmits / receives data to / from the base station in the number of subbands corresponding to the adaptable frequency bandwidth. . The subband used by the terminal 30 may be fixed until the connection with the base station is disconnected. For example, the subband may be switched each time an inter-carrier handoff occurs. In this case, the base station notifies the terminal 30 of a new subband ID by F-SCCH or preamble every time the subband is switched.

FIG. 15 shows an example of subband ID assignment results for three types of terminals (AT1, AT2, AT3) having different adaptable frequency bands.
Here, the physical subcarrier 52 is divided into four subbands SB0 to SB3, the terminal AT1 has one subband SB0 (subband ID = 0), and the terminal AT2 has two subbands SB0 to SB3. The subbands SB2 and SB3 (subband ID = 2, 3) and the terminal AT3 are in a state where four subbands SB0 to SB3 (subband ID = 0, 1, 2, 3) are assigned. .

In the cellular radio communication system of the present invention, each terminal 30 transmits / receives data to / from the base station 10 thereafter within the subband range designated by the base station 10 using the subband ID. For actual data transmission / reception, a subcarrier group corresponding to the hop port block group designated by the base station 10 using the node ID is used within the range of the subband designated by the subband ID.
In the uplink and the downlink, the used subband and the assigned node ID can be selected independently.

In the cellular radio communication system of the present invention, after the base station 10 notifies the terminal 30 of the above-described subband information, data communication is executed in the following procedure.
FIG. 16 is a sequence diagram illustrating an example of data communication in the downlink from the base station 10 to the terminal 30.

  The base station 10 selects one or a plurality of hop port blocks (logical subcarriers) in an idle state according to the bandwidth (downlink request bandwidth) required for data transmission in the downlink, A FLAB (Forward Link Assignment Block) indicating a node ID corresponding to the hop port block is transmitted to the terminal 30 (SQ101). When the downlink request band corresponds to a plurality of hop port blocks, the ID of the upper node located at the apex of the plurality of hop port blocks on the channel tree is set in FLAB.

  Selection of the node ID to be notified to the terminal 30 is performed by the node assignment unit 124 of the downlink control unit 12. The node assign unit 124 is notified of the terminal ID and the requested downlink bandwidth from the main control unit every time data is transmitted to the terminal 30. The node assignment unit 124 searches the terminal management table 200 of the memory 18 for the assigned subband 203 corresponding to the terminal ID, and the logical subcarrier (hop port) corresponding to the assigned subband 203 indicated by the channel tree configuration information table 180. A free logical subcarrier corresponding to the requested bandwidth in the downlink is selected from among the block IDs), a node ID to be notified to the terminal is determined, and the FLAB generation unit 123 is notified. Thereafter, the node assignment unit 124 rewrites the downlink status 182 of the selected logical subcarrier in the channel tree configuration information table 180 to the use state, and notifies the hop port mapping unit 115 of the node ID.

  The FLAB generation unit 123 generates a FLAB including the node ID determined by the node assignment unit 124 and outputs the FLAB to the control information encoding / modulation unit 119. The control information encoding / modulating unit 119 encodes the FLAB and outputs the encoded FLAB to the hop port mapping unit 115 as a transmission signal of F-SCCH (Forward Link Shared Control Channel). As a result, the FLAB including the node ID is transmitted to the terminal 30 via F-SCCH (Forward Link Shared Control Channel). Thereafter, downlink data addressed to the terminal 30 is input from the modulation unit 114 to the hop port mapping unit 115. Downlink data addressed to the terminal 30 is mapped to a subcarrier corresponding to the node ID notified from the node assign unit 124 and transmitted through a downlink data channel F-DCH (Forward Link Data Channel).

  Here, the hop port mapping unit 115 holds channel tree information, and when notified of a node ID from the node assign unit 124, converts the notified node ID into a plurality of base node IDs according to the channel tree information. It is assumed that a function is provided. If the hop port mapping unit 115 does not hold channel tree information, the node assigning unit 124 specifies a base node ID subordinate to the upper node ID in the channel tree configuration information table 180 of the memory 18, These base node IDs may be notified to the hop port mapping unit 115.

  The FLAB transmitted from the base station 10 using the F-SCCH and the downlink data transmitted using the F-DCH are received by the terminal 30 and input from the wireless transmission / reception circuit 37 to the baseband receiving unit 33. The FLAB transmitted on the F-SCCH is transferred from the hop port demapping unit 334 of the baseband receiving unit 33 to the control information demodulation / decoding unit 339, and from the control information demodulation / decoding unit 339 to the FLAB of the downlink control unit 34. The data is input to the acquisition unit 343.

  The FLAB acquisition unit 343 extracts the node ID from the received FLAB, and notifies the node designation unit 345 of the node ID. The node designation unit 345 notifies the hop port demapping unit 334 of the node ID. Here, the hop port demapping unit 334 holds channel tree information, and when notified of a node ID from the node specifying unit 345, converts the notified node ID into a plurality of base node IDs according to the channel tree information. It is assumed that the data received in the hop port block corresponding to these base node IDs is output to the demodulator 335. If the hop port demapping unit 334 does not hold the channel tree information, the node designation unit 345 converts the node ID extracted from the FLAB into the base node ID according to the channel tree configuration information held in the memory 380. The base node ID may be notified to the hop port demapping unit 334.

  Retransmission control by HARQ (Hybrid Automatic Repeat Request) is applied to the terminal 30 shown in FIG. If there is an error in the received data as a result of CRC determination of the received data processed by the demodulating unit 335, the depreciation unit 336, and the decoding unit 337, the ACK / NAK generating unit 341 generates a NAK (Negative Acknowledgement), and the received data is If it is correct, the ACK / NAK generation unit 341 generates an ACK (Acknowledgement). The ACK / NAK signal generated by the ACK / NAK generation unit 341 is input to the control information encoding / modulation unit 319 and transmitted to the base station 10 through an R-ACKCH (Reverse Link Acknowledgment Channel).

  In the sequence diagram of FIG. 16, since the terminal 30 failed to decode the data received in SQ101, it transmits a NAK (Negative Acknowledgement) to the base station 10 (SQ102). The NAK is input to the control information demodulation / decoding unit 139 from the hop port demapping unit 134 in the baseband receiving unit 13 of the base station 10, and the retransmission control unit of the downlink control unit 12 from the control information demodulation / decoding unit 139. 121.

  HARQ retransmission control is performed by the retransmission control unit 121 and the repetition unit 113, and retransmission data is transmitted from the base station 10 to the terminal 30 via the downlink data channel F-DCH (SQ103), and the terminal 30 receives the retransmission data. If successful, the ACK (Acknowledgement) generated by the ACK / NAK generation unit 341 is transmitted to the base station 10 using the R-ACKCH (SQ104). When the base station 10 receives an ACK response from the terminal 30, data transmission from the base station 10 to the terminal 30 is temporarily terminated, and a completion signal is transmitted from the control information demodulation / decoding unit 139 to the subband management unit 15. At this time, the subband management unit 15 returns the downlink status of the assigned node ID of the terminal 30 indicated by the terminal management table 200 to the empty state in the channel tree configuration information table 180.

FIG. 17 is a sequence diagram illustrating an example of uplink data communication from the terminal 30 toward the base station 10.
When transmission data is generated, the terminal 30 transmits a subcarrier allocation request to the base station 10 through an uplink request channel (R-REQCH: Reverse Link Request Channel) (SQ201). The subcarrier allocation request is generated by the control information encoding / modulating unit 319 in response to a request from the main control unit. The subcarrier allocation request transmitted from the terminal 30 is received by the base station 10 and is input from the hop port demapping unit 134 to the control information demodulating / decoding unit 139 in the baseband receiving unit 13, and the control information demodulating / decoding unit 139 to the node assign unit 145.

  The node assignment unit 145 searches the terminal management table 200 of the memory 18 for an allocation subband 203 corresponding to the terminal ID of the subcarrier allocation request source, refers to the channel tree configuration information table 180, and refers to the allocation subband 203. And select a free logical subcarrier (base node ID) corresponding to the requested bandwidth indicated by the subcarrier allocation request in the uplink, and determine an upper node ID to be notified to the terminal. Then, the RLAB generation unit 144 is notified. Thereafter, the node assigning unit 124 rewrites the uplink status 182 of the selected base node ID to the use state in the channel tree configuration information table 180, assigns the upper node ID to the terminal management table 200, and assigns the node ID 204 Remember as.

  The RLAB generating unit 144 generates an RLAB including the node ID determined by the node assigning unit 145 and outputs the RLAB to the control information encoding / modulating unit 119. The control information encoder / modulator 119 encodes the RLAB and outputs the encoded RLAB to the hop port mapping unit 115 as a F-SCCH (Forward Link Shared Control Channel) transmission signal. As a result, the RLAB including the node ID is transmitted to the terminal 30 via the F-SCCH (Forward Link Shared Control Channel) (SQ202).

  The RLAB is received by the terminal 30, passed from the hop port demapping unit 334 of the baseband receiving unit 33 to the control information demodulation / decoding unit 339, and from the control information demodulation / decoding unit 339 to the RLAB of the uplink control unit 32. Input to the acquisition unit 322. The RLAB acquisition unit 322 extracts the node ID from the received RLAB, notifies the node designation unit 324 of the node ID, and permits the main control unit to transmit data. The node designation unit 324 notifies the hop port mapping unit 315 of the node ID.

  Here, the hop port mapping unit 315 holds channel tree information, and when the node ID is notified from the node specifying unit 324, the notified node ID is converted into a plurality of base node IDs according to the channel tree information. Suppose that transmission data is mapped to hop port blocks corresponding to these base node IDs. If the hop port mapping unit 315 does not hold the channel tree information, the node designation unit 324 converts the node ID into the base node ID according to the channel tree configuration information held in the memory 380, and the base node ID May be notified to the hop port mapping unit 315.

  As a result, transmission data output from the main control unit is input to the hop port mapping unit 315 via the encoding unit 312, the repetition unit 313, and the modulation unit 314, and the hop port mapping unit 315 transmits the transmission data to the base station. It will be mapped to the specified hop port.

  The transmission data is mapped by the permutation unit 316 to subcarriers in the subband designated in advance by the subband ID, and transmitted as uplink OFDM data channel (R-ODCH: Reverse Link OFDM Data Channel). Is transmitted to the base station 10 (SQ203).

  The base station 10 receives the data transmitted by the terminal 30 on the R-ODCH on a subcarrier designated in advance by a node ID. In the base station 10, the node assignment unit 145 of the uplink control unit 14 notifies the hop port demapping unit 134 of the allocated node ID 204 of the terminal 30 indicated by the memory 18 at the R-ODCH data reception timing. As a result, the hop port demapping unit 134 extracts the transmission data from the terminal 30 from the hop port specified by the node ID 204, and outputs it to one of the demodulation units 135-1 to 135-n.

  Similar to the terminal 30, retransmission control by HARQ is applied to the baseband receiving unit 13 of the base station 10. In the sequence of FIG. 17, as a result of the CRC determination performed on the received data of SQ 203, a NAK is transmitted from the base station 10 to the terminal 30 through an uplink ACK channel (F-ACKCH: Forward Link Acknowledgment Channel) (SQ 204). 30 shows a case where the data is retransmitted on the R-ODCH (SQ205), and the base station 10 transmits an ACK to the terminal 30 on the F-ACKCH for the data received on the SQ205 (SQ206).

  The operation of the base station 10 in SQ204 and SQ206 is similar to the operation of the terminal in SQ102 and SQ104 described in FIG. 16, and the operation of the terminal 30 in SQ205 is similar to the operation of the base station in SQ103 described in FIG. Therefore, detailed description with reference to FIGS. 4 and 5 is omitted.

FIG. 18 shows an example of the FLAB and RLAB formats transmitted from the base station 10 to the terminal 30 to notify the node ID.
FLAB and RLAB are PFs including a Persistent field 701 indicating a subcarrier allocation period, a NodeID field 702 in which a node ID for specifying an allocated subcarrier is set, and packet format information indicating a modulation order and an error correction coding rate. (Packet Format) field 703, TD (Transmit Diversity) field 704 indicating information on use such as transmission diversity and spatial multiplexing function, and HARQ field 305 indicating a retransmission period in HARQ retransmission control. FLAB and RLAB further include, as option fields, an Extended Tx field 706 indicating whether or not to use the Extended Transmission mode and a Supplemental field 707 indicating whether or not to use the Supplemental Transmission mode.

  In the cellular radio communication system of the present invention, as described with reference to FIG. 11, the base station 10 assigns one or more subbands to be used for data transmission / reception in advance according to the adaptive frequency band of the terminal 30. 16 and FIG. 17, each time data is transmitted / received, the base station 10 assigns a hop port group corresponding to the requested bandwidth to the terminal within the range of the designated subband, and assigns it. The node ID indicating the hop port group is notified to the terminal 30.

  In the example illustrated in FIG. 15, the terminal AT1 uses the subband SB0 as an adaptive frequency band, and has four base nodes (node ID = 15 to 18) whose nodes are nodes having a node ID “3” on the channel tree. ) Can be assigned. Therefore, for example, when the base station 10 notifies the terminal AT1 of the node ID “7”, the subband SB0 includes two hop port blocks corresponding to the base nodes having the node IDs “15” and “16”. The permutation allows data transmission / reception using 16 (= 8 × 2) physical subcarriers as indicated by blocks B1 and B3. If the node ID “3” is assigned, the terminal AT1 can perform data transmission / reception using 32 (= 8 × 4) physical subcarriers which are the entire band of the subband SB0.

  Since the terminal AT2 uses the subbands SB2 and SB3 as adaptive frequency bands, eight base nodes (node ID = 23 to 30) having a node ID “2” as a vertex can be assigned. Therefore, for example, when the base station 10 notifies the terminal AT2 of the node ID “6”, the subband SB3 corresponds to the base node of the node ID = “27”, “28”, “29”, “30”. The four hop port blocks are permutated, and data transmission / reception using 32 (= 8 × 4) physical subcarriers becomes possible as indicated by blocks B12 to B15.

  Since the selection of the node ID depends on the free state of the logical carrier (hop port) in the channel tree configuration information table, the base station is configured for the required bandwidth of 32 physical subcarriers necessary for communication with the terminal AT2. 10 may allocate, for example, four base nodes of node ID = “25” to “28”. In this case, the terminal AT2 uses 32 (= 8 × 4) physical subcarriers included in the two blocks B9 and B10 in the subband SB2 and the two blocks B13 and B15 in the subband SB3. .

  Since the terminal AT3 is adapted to the subbands SB0 to SB3, which are all frequency bands of the base station 10, the base station 10 can designate any free base node. In the example of FIG. 15, when the requested bandwidth of the terminal AT3 is 32 (= 8 × 4) physical subcarriers, node ID = 4 is assigned, and base node ID = “19”, “20”, “21”, “22” The four hop port blocks corresponding to "" are permutated to the blocks B4 to B7 in the subband SB1. When the requested bandwidth of the terminal AT3 is, for example, 16 (= 8 × 2) physical subcarriers, the base station 10 has idle node IDs = “8”, “9”, “10”, “11”, “ 12 ”can be assigned to the terminal AT3.

  As is clear from the above embodiments, according to the present invention, even when a plurality of types of terminals having different adaptive frequency bandwidths are accommodated simultaneously, the base station can efficiently allocate subcarriers to each terminal. It becomes. Also, by dividing the frequency band that can be used in the base station into a plurality of subbands, and considering the load for each subband, assigning the used subbands to each terminal and assigning hop ports, It becomes possible to distribute the traffic load in the frequency band.

The figure which shows schematic structure of the OFDMA cellular radio | wireless communications system with which this invention is applied. The figure for demonstrating the permutation from the channel tree applied to the conventional OFDMA cellular radio | wireless communications system, and a hop port to a physical subcarrier. The figure for demonstrating the permutation from the channel tree applied to the OFDMA cellular radio | wireless communications system of this invention, and a hop port to a physical subcarrier. The figure which shows one Example of the radio | wireless transmission / reception part of the base station 10 used for the OFDMA cellular radio | wireless communications system of this invention. The figure which shows one Example of the terminal 30 applied to the OFDMA radio | wireless communications system of this invention. The figure which shows the content of the memory 18 which the subband management part 15 of the base station 10 refers. The figure which showed typically an example of the channel tree structure information table 180 formed in the memory 18. FIG. The figure which shows an example of the subband management table 190 formed in the memory 18. The figure which shows one example of the terminal management table 200 formed in the memory 18. FIG. The figure which shows the content of the memory 380 which the subband management part 35 of the terminal 30 manages. The figure which shows the communication sequence of the subband information performed between the base station 10 and the terminal 30 prior to data communication in the OFDMA radio | wireless communications system of this invention. The figure which shows an example of the format of the preamble transmitted to each terminal 30 from the base station 10. FIG. The figure which shows an example of the format of the SystemInfo block 410 transmitted by F-PBCCH41 of a preamble. The figure which shows an example of the format of the QuickChannelInfo block 420 transmitted by F-SBCCH42 of a preamble. The figure which shows an example of the allocation result of subband ID with respect to three types of terminals from which an adaptable frequency band differs. The sequence diagram which shows an example of the data communication in the downlink which goes to the terminal 30 from the base station 10 in the OFDMA radio | wireless communications system of this invention. The sequence diagram which shows an example of the data communication in the uplink which goes to the base station 10 from the terminal 30 in the OFDMA radio | wireless communications system of this invention. The figure which shows an example of the format of FLAB and RLAB transmitted to the terminal 30 from the base station 10 in order to notify node ID.

Explanation of symbols

10: base station, 20: base station controller, 30: terminal,
50: Channel tree, 51: Hop port, 52: Physical subcarrier, 53: Permutation, SB: Subband, GT: Global tree, LT: Local tree,
11, 31: Baseband transmission unit, 12, 34: Downlink control unit, 13, 33: Baseband reception unit, 14, 32: Uplink control unit, 15, 35: Subband management unit, 16: Broadcast information generation unit , 17, 37: wireless transmission / reception circuit, 19, 39: antenna.

Claims (20)

A communication method between a base station and a terminal in an OFDMA cellular radio communication system, wherein a radio frequency band used in the base station is divided into a plurality of subbands each including a predetermined number of physical subcarriers,
The base station selecting one or a plurality of subbands applicable to the terminal from the plurality of subbands, and notifying the terminal as an assigned subband;
When the base station performs data communication with the terminal, and selects a group of subcarriers used for data communication within the range of the allocated subband, and notifies the terminal as the allocated subcarrier. ,
OFDMA data using the allocated subcarriers by the terminal and the base station performing modulation symbol transfer between logical subcarriers and physical subcarriers within the range of the allocated subbands. A communication method characterized by performing transmission and reception.   The base station and the terminal perform modulation symbol transfer between the subcarriers according to a localized permutation pattern prepared in advance corresponding to each subband. The communication method according to 1.   3. The communication method according to claim 1, wherein the base station notifies the terminal of the assigned subband on a downlink shared control channel of an OFDMA cellular radio communication system.   The communication method according to claim 1 or 2, wherein the base station notifies the terminal of the allocated subband by a preamble transmitted through a broadcast information channel of an OFDMA cellular radio communication system. . The bandwidth of the logical subcarrier is divided into a plurality of hop port subgroups corresponding to the subband, and each hop port subgroup includes a plurality of hop port blocks each including a predetermined number of logical subcarriers,
The base station and the terminal manage the logical subcarrier and the physical carrier by a channel tree including a plurality of hierarchized nodes, and the channel tree includes a plurality of hops included in a band of the logical subcarrier. A plurality of base nodes associated with a port block, and a plurality of upper nodes that hierarchize the base node in a binary tree configuration, wherein the base station is an identifier assigned to each node in the channel tree. The communication method according to any one of claims 1 to 4, wherein the allocation subcarrier is notified to the terminal by designating one of the following. The base station periodically broadcasts the bandwidth of the radio frequency band and the number of subbands as broadcast information;
After the terminal receives the broadcast information, the terminal has a step of notifying the base station of the adaptive frequency bandwidth of the terminal,
The base station selects at least one subband to be allocated to the terminal according to the adaptive frequency bandwidth notified from the terminal, and notifies the terminal as the allocated subband. The communication method according to any one of claims 1 to 5.   The communication method according to claim 6, wherein the base station broadcasts the broadcast information using a preamble transmitted through a broadcast information channel of an OFDMA cellular radio communication system.   The communication method according to claim 7, wherein the base station transmits the preamble for each subband.   The said terminal notifies the said adaptive frequency bandwidth to the said base station in the connection procedure to the said base station performed after receiving the said alerting | reporting information, The said base station is characterized by the above-mentioned. The communication method described in 1.   The communication method according to claim 9, wherein the terminal notifies the base station of the number of subbands as information indicating the adaptive frequency bandwidth. In an OFDMA wireless communication system comprising a base station that divides and manages a radio frequency band into a plurality of subbands each including a predetermined number of physical subcarriers and at least one terminal that is wirelessly connected to the base station There,
The base station
Subband management for selecting the number of subbands corresponding to the adaptive frequency bandwidth from the plurality of subbands and notifying the terminal as allocated subbands when notified of the adaptive frequency bandwidth from the terminal And
A link controller that selects a group of subcarriers to be used for data communication within the range of the allocated subbands and notifies the terminal as allocated subcarriers when performing data communication with the terminal;
Each of the above terminals
A first permutation unit that transfers modulation symbols on a plurality of physical subcarriers included in a signal received from the base station to a plurality of logical subcarriers; and a plurality of logics output from the first permutation unit A receiving unit including a demapping unit that converts modulation symbols on subcarriers into modulation symbols for each channel;
A mapping unit that maps modulation symbols of a plurality of channels to be transmitted to the base station to a plurality of logical subcarriers, and a modulation unit that transfers modulation symbols on the plurality of logical subcarriers output from the mapping unit to a plurality of physical carriers. A transmission unit including two permutation units;
A subband management unit for specifying a modulation symbol transfer range in the first permutation unit and the second permutation unit according to the assigned subband notified from the base station;
When data communication is performed with the base station, according to the assigned subcarrier notified from the base station, a logical subcarrier group from which the data modulation symbol is extracted in the demapping unit, and mapping of the data modulation symbol in the mapping unit A wireless communication system comprising a node designating unit that identifies a logical subcarrier group as a destination.   The first permutation unit and the second first permutation unit of the terminal are configured to transmit modulation symbols for data between the subcarriers according to a localized permutation pattern corresponding to the allocated subcarrier. The wireless communication system according to claim 11, wherein transfer is performed. The base station has a broadcast information generator that periodically broadcasts the bandwidth of the radio frequency band and the number of subbands as broadcast information,
After the subband management unit of the terminal receives the broadcast information, it notifies the base station of the adaptive frequency bandwidth of the terminal,
The subband management unit of the base station selects at least one subband to be allocated to the terminal according to the adaptive frequency bandwidth notified from the terminal, and notifies the terminal as the allocated subband. The wireless communication system according to claim 11, wherein   The base station includes a preamble encoding / modulating unit for generating a preamble including broadcast information generated by the broadcast information generating unit and periodically broadcasting the broadcast information on a broadcast information channel. 13. The wireless communication system according to 13.   The radio communication system according to claim 14, wherein the preamble encoding / modulating unit generates the preamble for each subband. An OFDMA base station that communicates wirelessly with a plurality of terminals,
The radio frequency band is divided and managed into a plurality of subbands each including a predetermined number of physical subcarriers, and when the adaptive frequency bandwidth is notified from one of the plurality of terminals, the plurality of subbands A subband management unit that selects the number of subbands according to the adaptive frequency bandwidth from among them, and notifies the terminal as an assigned subband;
A link control unit for selecting a group of subcarriers used for data communication within the range of the allocated subbands and notifying the terminal as allocated subcarriers when performing data communication with the terminal;
A transmitter that maps a modulation symbol sequence generated from transmission data to the terminal to an assigned subcarrier selected by the link controller;
A receiving unit that extracts a modulation symbol sequence of a data channel received from the terminal from an assigned subcarrier selected by the link control unit;
A base station comprising the transmitter and a radio transceiver circuit connected to the receiver. A first permutation unit configured to transfer modulation symbols on a plurality of physical subcarriers included in a reception signal input from the radio transmission / reception circuit to a plurality of logical subcarriers; and the first permutation. A demapping unit for converting modulation symbols on a plurality of logical subcarriers output from the unit into modulation symbols for each channel,
The transmission unit maps a modulation symbol of a plurality of channels serving as a transmission signal to a plurality of logical subcarriers, and moves modulation symbols on the plurality of logical subcarriers output from the mapping unit to a plurality of physical carriers. A second permutation section to be replaced,
The modulation symbol transfer in the first permutation unit and the second permutation unit is performed according to a permutation pattern prepared for each subband. base station. The mapping unit maps a modulation symbol serving as transmission data addressed to each terminal to a logical subcarrier according to an assigned subcarrier specified by the link control unit,
The base station according to claim 16, wherein the demapping unit extracts a modulation symbol serving as reception data from each terminal from a logical subcarrier according to an assigned subcarrier specified by the link control unit. Control information encoding / modulating unit for converting the control information generated by the link control unit and the control information indicating the assigned subband selected by the subband generating unit into a modulation symbol string of a control channel And a preamble encoding / modulating unit that converts the bandwidth of the radio frequency band and the number of subbands into a modulation symbol string of a broadcast information channel,
The mapping unit maps a modulation symbol sequence of a data channel indicating transmission data addressed to the terminal, a modulation symbol sequence of the control channel, and a modulation symbol sequence of the broadcast information channel to the logical subcarrier. The base station according to claim 17.   The base station according to claim 19, wherein the preamble encoding / modulating unit generates a modulation symbol string of the broadcast information channel for each subband.

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