Ranging method through relay station in ieee802.16, program, and system

The present invention relates to a range method, a program and a system via a relay station in IEEE802.16.

IEEE802.16 is a standard for high-speed wireless access systems that can provide BWA (Broadband Wireless Access) services. Currently, at the IEEE802.16 standardization meeting, studies have begun on MMR (Mobile Multihop Relay) technology, which expands the coverage area by relaying data, to specify medium access control and the physical layer. ing. According to this MMR technology, the base station BS (Base Station) communicates with the fixed station SS (Subscriber Station) or the mobile station MS (Mobile Subscriber Station) within the base station BS, and also within the base station area BS. It is also possible to communicate with a fixed station SS or a mobile station MS outside the base station BS area via the relay station RS (Relay Station).

The IEEE802.16 high-speed wireless access system is basically a standard aimed at providing BWA services for fixed-station SS (see, for example, Non-Patent Document 1, IEEE802.16-2004). Two network topologies, PMP (Point-to-Multipoint) and Mesh, are specified here. PMP basically configures a network with "BS: SS = 1: many" like a general cellular system. On the other hand, Mesh configures a multi-hop network of mobile station MSs. As the modulation method, a single carrier method, an OFDM (Orthogonal Frequency Division Multiple) method, and an OFDMA (OFDM Access) method are adopted.

There is also a standard that defines the initial range sequence of the OFDMA method, which is a modified version of Non-Patent Document 1 (see, for example, Non-Patent Document 2). First, the mobile station MS generates a random initial range code and transmits it to the base station BS by CDMA (Code Division Multiple Access). On the other hand, the base station BS returns the ranging response RNG-RSP (Ranging Response) to the mobile station MS. This message exchange is repeated a plurality of times in order to adjust the transmission power and timing between the base station BS and the mobile station MS. When these adjustments are completed, the base station BS transmits a successful RNG-RSP to the mobile station MS. On the other hand, the mobile station MS transmits a rangeing request RNG-REQ (Ranging Request) to the base station BS. The base station BS assigns a connection identifier CID (Connection IDentifier) to the mobile station MS, and transmits RNG-RSP including the CID to the mobile station MS.

According to Non-Patent Documents 1 and 2, the relay function for the purpose of expanding the coverage area is not considered at all. When relaying power amplification, the relay station RS simply amplifies and transfers the desired Burst Profile determined by the communication status between the relay station RS and the fixed station SS. Therefore, the communication status between the base station BS and the relay station RS is not taken into consideration, and as a result, the matching between the base station BS, the relay station RS, and the fixed station SS cannot be obtained.

In addition, the coverage area can be expanded by using the Mesh topology of the IEEE802.16-2004 standard. However, Mesh is treated as an option and is not compatible with PMP in terms of frame configuration. Also, compared to PMP, there is more frame overhead, which affects throughput. Duplex schemes only support TDD (Time Division Duplex).

Furthermore, the frequency band used is assumed to be 2 GHz or higher. Due to its frequency characteristics, the reception status of the fixed station SS becomes unstable due to the influence of the terrain and surrounding buildings, and there is a high possibility that it will not be available indoors or underground outside the service area. In such a situation, PMP of the same standard has no choice but to install a new base station BS.

Furthermore, there is also a standard for high-speed wireless access systems modified from IEEE802.16-2004 for the purpose of providing BWA services for mobile station MS (see, for example, Non-Patent Document 3, IEEE802.16e). Here, only PMP is specified as the network topology.

FIG. 1 is a configuration diagram of a pseudo-random number bit string PRBS (Pseudo Random Binary Sequence) generator that generates an OFDMA-type range code.

The lower 7 bits (s0 to s6) of the 15 bits of the PRBS seed are assigned to UL_PermBase (UpLink Permutation Base) to generate the range code. UL_PermBase: Integer 0 to 69 (70 ways) Ranged code length: 144 bits Available code number: 256 ways

The base station BS uses a subgroup S (0 to 255) of a plurality of codes, and each code shown below exists in the range of S ~ ((S + O + N + M + L) mod 256). N code (initial range) 144 × (S mod 256) times ~ 144 × ((S + N) mod 256) -1 times M code (Periodic ranging) 144 × ((N + S) mod 256) times ~ 144 × ((N + M + S) mod 256) -1 times L code (bandwidth request) 144 × ((N + M + S) mod 256) times ~ 144 × ((N + M + L + S) ) mod 256) -1 times O code (handjob ranging) 144 × ((N + M + L + S) mod 256) times ~ 144 × ((N + M + L + O + S) mod 256) -1 times

According to the OFDMA method, since PermBase supports subcarrier allocation, the frequency band differs for each PermBase. Therefore, by using different PermBase, mutual interference is suppressed.

<nplcit num="1"><text>IEEE Std 802.16-2004, IEEE Standard for Local and metropolitan area networks, Part 16, "Air Interface for Fixed Broadband Wireless Access Systems"</text></nplcit><nplcit num="2"><text>IEEE P802.16-2004 / Cor1 / D5, Draft IEEE Standard for Local and metropolitan area networks, Corrigendum to IEEE Standard for Localand Metropolitan Area Networks --Part 16, "Air Interface for Fixed Broadband Wireless Access Systems"</text></nplcit><nplcit num="3"><text>IEEE P802.16e / D12, Draft IEEE Standard for Localand metropolitan area networks, Part 16, "Air Interface for Fixed and Mobile Broadband Wireless Access Systems, Amendment for Physical and Medium AccessControl Layers for Combined Fixed and Mobile Operation in Licensed Bands"</text></nplcit>

<p> When the base station BS in IEEE802.16 communicates with the mobile station MS via the relay station RS, the number of mobile station MSs communicating with the base station BS becomes enormous. At this time, the base station BS separately requires a sequence other than the standard in order to specify the relay station RS via which the mobile station MS passes. However, the sequence for identifying the network topology becomes a load on the entire network.</p><p> Therefore, according to the present invention, for a high-speed wireless access system to which IEEE802.16 is applied, it is possible to improve the efficiency of network resources by simply specifying the network topology in which the relay station RS is mediated. The purpose is to provide methods, programs and systems.</p>

<p> According to the present invention, which is a ranging method in the OFDMA system of IEEE802.16, a mobile station in which seed information for generating each code of initial ranging, Periodic ranging, Bandwidth request, and Handover ranging exists in the base station range. It is characterized in that it is divided in advance into a basic domain assigned to the base station and a relay domain assigned to a relay station existing in the base station area and a mobile station existing in the relay station area.</p><p> According to another embodiment in the range method of the present invention, the relay domain is assigned to the mobile station and the second relay station existing in the first relay station for each seed information assigned to the first relay station. It is also preferable that the assigned domain is divided in advance.</p><p> According to another embodiment in the range method of the present invention, it is also preferable that the seed information is UL_PermBase, which is a part of the bit information input to the pseudo-random number bit string generator.</p><p> According to another embodiment of the range method of the present invention, the first step in which the base station transmits the preamble to the relay station and the preamble generated by the relay station based on the seed information for the relay station assigned to the relay station are transmitted to the mobile station. In the second step of transmission, the mobile station determines the seed information to be assigned to the mobile station from the relay domain, generates an initial range code using the seed information, and returns the initial range code to the relay station. In the third step, the relay station transfers the initial range code received from the mobile station to the base station, and the base station uses the initial range code, and the mobile station moves through the relay station. It is also preferable to have a fifth step of recognizing that they are communicating.</p><p> According to the present invention, it is a program that executes a range processing by a computer mounted on a communication device in the OFDMA method of IEEE802.16, and generates each code of initial range, Periodic ranging, Bandwidth request, and Handover ranging. Seed information is divided in advance into a basic domain assigned to a mobile station existing in the base station area, a relay station existing in the base station area, and a relay domain assigned to a mobile station existing in the relay station area. It is characterized by running a computer in such a way.</p><p> According to the present invention, it is a relay station in the OFDMA system of IEEE802.16, and the seed information for generating each code of initial ranging, Periodic ranging, Bandwidth request, and Handover ranging exists in the base station range. It is divided into a basic domain assigned to the base station and a relay domain assigned to a relay station existing in the base station area and a mobile station existing in the relay station area, and the relay domain is assigned to the first relay station. For each seed information, the mobile stations existing in the first relay station area and the domains assigned to the second relay station are classified in advance, and the seed information determination for determining the seed information for the relay station from the relay domains is performed. It is characterized by having a means, a preamble transmission means for transmitting a preamble generated by seed information for a relay station to a mobile station, and a range code transmission means for transferring an initial range code received from the mobile station to a base station. ..</p><p> According to another embodiment in the relay station of the present invention, it is also preferable that the seed information is UL_PermBase, which is a part of the bit information input to the pseudo-random number bit string generator.</p><p> According to the present invention, it is a base station in the OFDMA system of IEEE802.16, and the seed information for generating each code of initial ranging, Periodic ranging, Bandwidth request, and Handover ranging exists in the base station range. It is divided into a basic domain assigned to the base station and a relay domain assigned to a relay station existing in the base station area and a mobile station existing in the relay station area, and the relay domain is assigned to the first relay station. For each seed information, the mobile stations existing within the first relay station and the domains assigned to the second relay station are classified in advance, and the seed information of the received initial range code is the basic domain or the relay domain. Ranged code determination means for determining whether or not, and when the seed information is a relay domain, a relay route determination means for identifying the relay station through which the mobile station passes and determining the relay route, and a route for holding the relay route in the route table. It is characterized by having a table holding means and a map scheduling means for scheduling transmission / reception timing according to a route table.</p><p> According to another embodiment in the base station of the present invention, it is also preferable that the seed information is UL_PermBase, which is a part of the bit information input to the pseudo-random number bit string generator.</p><p> According to the present invention, it is a mobile station in the OFDMA system of IEEE802.16, and the seed information for generating each code of initial ranging, Periodic ranging, Bandwidth request, and Handover ranging exists in the base station range. It is divided in advance into a basic domain assigned to the base station and a relay domain assigned to a relay station existing in the base station area and a mobile station existing in the relay station area, and the relay domain is assigned to the first relay station. The mobile stations existing in the first relay station range and the domains assigned to the second relay station are divided in advance for each seed information, and the seed information that generated the received preamble is the basic domain or the relay domain. Using the preamble determination means for determining whether or not, and when the seed information is a relay domain, the seed information determination means for determining the seed information for the mobile station from the domains based on the seed information that generated the received preamble, and the seed information. Initial ranging, Periodic ranging, Bandwidth request, Handover It is characterized by having a ranging code generation means for generating each code of ranging and a range processing means for performing a range processing using an initial range code.</p><p> According to another embodiment in the mobile station of the present invention, the seed information is UL_PermBase, which is a part of bit information input to the pseudo-random number bit string generator.</p>

<p> According to the ranging method and the like of the present invention, the network topology in which the relay station RS is interposed can be easily specified for the IEEE802.16 high-speed wireless access system.</p><p> According to the present invention, the range code used in the OFDMA method range processing is extended for a relay station. Such a range code assignment can be associated with a network topology that includes a relay station. The base station can identify the relay station through which the mobile station is passing, grasp the route of the entire network, and allocate the band based on the route information.</p>

Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the drawings.

The UL_PermBase that can be assigned by the PRBS generator is 7 bits (128 ways), while the UL_PermBase specified by the conventional standard is 0 to 69 (70 ways). UL_PermBase = 0 to 69 is the basic domain assigned to the mobile station MS existing in the base station BS area. On the other hand, in the present invention, 70 to 128 (58 ways) of UL_PermBase, which are not defined by the conventional standard, are assigned according to the network topology. 70 to 128 of this UL_PermBase are relay domains assigned to the relay station RS and the mobile station MS that communicates with the base station BS via the relay station RS.

Table 1 shows the UL_PermBase allocation in the present invention.<tables num="1"><img file="JP2007201848A_D0001.tif" /></tables>

According to Table 1, the mobile station MS existing in the base station BS range uses an integer of UL_PermBase = 0 to 69. The relay station RShop1 existing in the base station BS uses an integer of UL_PermBase = 70, 80, .... The mobile station MS existing in the relay station RShop1 of UL_PermBase = 70 uses an integer of UL_PermBase = 71 to 74. The relay station RShop2 existing in the relay station RShop1 of UL_PermBase = 70 uses UL_PermBase = 75. The mobile station MS existing in the relay station RShop2 of UL_PermBase = 75 uses an integer of UL_PermBase = 76 to 79. As described above, the present invention relates to initial rangeing, periodicranging, bandwidth request, and handover. UL_PermBase for generating each code of ranging is assigned to the mobile station MS existing in the base station BS area, the relay station RS existing in the base station BS area, and the mobile station existing in the relay station RS area. It is pre-divided into a relay domain assigned to the MS. The assigned UL_PermBase will represent the network topology.

FIG. 2 is a network system configuration diagram according to the present invention.

Figure 2 shows the network topology in which the relay station RS exists for the PMP of the IEEE802.16 high-speed wireless access system. Within the base station BS area, there are mobile stations MS1 and MS2 and relay stations RS1 and RS2. Within the relay station RS1, mobile stations MS3 and MS4 and relay station RS11 exist. In addition, mobile stations MS7 and MS8 exist within the relay station RS11. The mobile stations MS7 and MS8 communicate with the base station BS via the relay station RS11 and the relay station RS1. On the other hand, mobile stations MS5 and MS6 exist within the relay station RS2.

Next, UL_PermBase assigned by the relay station RS and the mobile station MS will be described.

Mobile stations MS1 and MS2 within the base station BS select an integer of UL_PermBase = 0 to 69 according to the prior art and use it as a part of the PRBS seed.

For the relay stations RS1 and RS2 within the base station BS, select the integer specified for the relay station from UL_PermBase = 70 to 127 (58 ways). According to FIG. 2, relay station RS1 assigns UL_PermBase = 70, and relay station RS2 assigns UL_PermBase = 80. Here, the relay station RS shares the UL_PermBase for the assigned base station BS with the DL_PermBase (DownlinkPermutation Base) for the mobile station MS. Therefore, the relay station RS uses its DL_PermBase for the Permutation of the preamble to be transmitted within the relay station RS range. As a result, the mobile station MS or the relay station RS that has received the preamble can recognize that the relay station is intervening.

The relay station RS1 transmits the preamble generated by DL_PermBase = 70 to the mobile stations MS3 and MS4 within the area. The mobile stations MS3 and MS4 and the relay station RS11 that have received this preamble recognize that they are within the range of the relay station RS1. Then, the mobile stations MS3 and MS4 select an integer of UL_PermBase = 71 to 74, and use that integer as a part of the PRBS seed. According to FIG. 2, the mobile station MS3 selects UL_PermBase = 71, and the mobile station MS4 selects UL_PermBase = 72.

The relay station RS2 transmits the preamble generated by DL_PermBase = 80 to the mobile stations MS5 and MS6 in the area. The mobile stations MS5 and MS6 that have received this preamble recognize that they are within the range of the relay station RS2. Then, the mobile stations MS5 and MS6 select an integer of UL_PermBase = 81 to 84, and use that integer as a part of the PRBS seed. According to FIG. 2, the mobile station MS5 selects UL_PermBase = 81, and the mobile station MS6 selects UL_PermBase = 82.

The UL_PermBase domain assigned to the higher relay station RS is assigned to the relay station RS (second hop from the base station BS) that exists within the range of the relay station RS (upper relay station RS on the first hop when viewed from the base station BS). Of these, a unique UL_PermBase is assigned in advance. According to Fig. 2 and Table 1, UL_PermBase = 75 is assigned to the relay station RS11.

The relay station RS11 transmits the preamble generated by DL_PermBase = 75 to the mobile stations MS7 and MS8 in the area. The mobile stations MS7 and MS8 that have received this preamble recognize that they are within the range of the relay station RS11. Then, the mobile stations MS7 and MS8 select an integer of UL_PermBase = 76 to 79 and use that integer as a part of the PRBS seed. According to FIG. 2, the mobile station MS7 selects UL_PermBase = 76, and the mobile station MS8 selects UL_PermBase = 77.

FIG. 3 shows a ranging sequence of the present invention between the base station BS and the mobile station MS existing outside the service area via the relay station RS.

(S301) The base station BS transmits the preamble generated by the pre-assigned DL_PermBase (any of 0 to 31, for example, 1) to the relay station RS (and mobile station MS) within the range. (S302) The relay station RS confirms that its DL_PermBase (1) is the basic domain (0 to 31), and assigns the seed information for the relay station (for example, 70) from the relay domains (70 to 127). The relay station RS transmits the preamble generated by DL_PermBase for RS (70), which is equivalent to the seed information for the relay station (70), to the mobile station MS within the range. (S303) Further, the base station BS transmits UL-MAP to the relay station RS. (S304) The relay station RS transfers the UL-MAP to the mobile station MS.

(S305) The mobile station MS selects one of the integers (eg 71) in the domain (71-74) based on the DL_PermBase for RS (70) that generated the received preamble and uses that integer as part of the PRBS seed. To do. The mobile station MS uses the PRBS seed to determine the initial range code by the output of the PRBS generator. The initial range code is transmitted to the relay station RS. (S306) The relay station RS transfers the received initial range code to the base station BS. The base station BS that has received the initial range code recognizes the following. -Recognize that the request is not from the mobile station MS within the base station BS because UL_PermBase is an integer other than 0 to 69. -Since UL_PermBase is divided into relay domains in advance (relay station 70: domains 71 to 74), specify the relay station RS in which the mobile station MS exists.

(S307) The base station BS secures a band for transmitting RNG-RSP to the mobile station MS within the relay station RS. (S308) The relay station RS transmits the RNG-RSP to the mobile station MS using the band allocated from the base station BS.

(S309) The sequence of S301 to S308 is repeated until the range processing is successful.

(S310) It is assumed that the range processing is successful. (S311) The base station BS again transmits the preamble generated by DL_PermBase (for example, 1) of the basic domain (0 to 31) to the relay station RS. (S312) The relay station RS transmits the preamble generated by DL_PermBase for RS (70), which is equivalent to the seed information for the relay station (70), to the mobile station MS within the range. (S313) Further, the base station BS transmits UL-MAP to the relay station RS. (S314) The relay station RS that has received the UL-MAP transfers the UL-MAP to the mobile station MS.

(S315) The mobile station MS transmits RNG-REQ with the desired burst profile (information such as modulation method and error correction FEC (Forward Error Correction)) between the relay station RS and the relay station MS to the relay station RS. To do. (S316) The relay station RS transfers the received RNG-REQ to the base station BS. (S317) The base station BS returns the RNG-RSP to the relay station RS. (S318) The relay station RS transfers the RNG-RSP to the mobile station MS.

FIG. 4 shows a ranging sequence of the present invention between the base station BS and the mobile station MS existing in the area via the relay station RS.

(S401) The base station BS transmits the preamble generated by the pre-assigned DL_PermBase (any of 0 to 31, for example, 1) to the mobile station MS (and relay station RS) within the range. (S402) Further, the base station BS transmits UL-MAP to the mobile station MS. (S403) The mobile station MS assigns an integer (for example, 1) of any of the base domains (0 to 69) to UL_PermBase, and makes that integer a part of the PRBS seed. The mobile station MS uses the PRBS seed to determine the initial range code by the output of the PRBS generator. The initial range code is transmitted to the base station BS. (S404) The base station BS returns the RNG-RSP to the mobile station MS.

(S405) The mobile station MS broadcasts a common code using a specific predetermined UL_PermBase (for example, 127) in order to search for a relay station RS existing in the vicinity. This common code is received not only by the relay station RS but also by the base station BS. (S406) The relay station RS that has received the common code broadcasts the preamble generated by the pre-assigned DL_PermBase for RS (any of 70 to 126, for example, 70) for a certain period of time. (S407) Upon receiving the preamble, the mobile station MS assigns an integer (eg 71) of any of the domains (71 to 74) based on DL_PermBase for RS (70) to UL_PermBase and makes that integer part of the PRBS seed. .. The mobile station MS uses the PRBS seed to determine the initial range code by the output of the PRBS generator. The initial range code is transmitted not only to the relay station RS but also to the base station BS. (S408) The base station BS that has received the initial range code recognizes the following. -Recognize that the request is not from the mobile station MS within the base station BS because UL_PermBase is an integer other than 0 to 69. -Since UL_PermBase is divided into domains in advance, specify the relay station RS in which the mobile station MS exists. Then, the base station BS secures a band for transmitting RNG-RSP to the mobile station MS under the relay station RS. The relay station RS transmits the RNG-RSP to the mobile station MS using the band allocated from the base station BS.

(S409) The base station BS transmits the preamble generated by the pre-assigned DL_PermBase (any of 0 to 31, for example, 1) to the mobile station MS within the range. (S410) The relay station RS also transmits the preamble generated by the pre-assigned DL_PermBase (any of 70 to 126, for example, 70) to the mobile station MS within the range. (S411) Further, the base station BS transmits UL-MAP to the mobile station MS. (S412) The mobile station MS determines a desired connection destination (base station BS or relay station RS) based on the reception status from the base station BS and the relay station RS. Then, the initial range code of the desired connection destination is broadcast. Since this initial range code is received by both the base station BS and the relay station RS, both stations can recognize which station is selected.

(S413) When the relay station RS is selected, the base station BS secures a band for transmitting RNG-RSP to the mobile station MS within the relay station RS. The relay station RS transmits the RNG-RSP to the mobile station MS using the band allocated from the base station BS.

(S414) The base station BS transmits UL-MAP to the mobile station MS. (S415) The mobile station MS transmits RNG-REQ to the base station BS. (S416) The base station BS returns the RNG-RSP to the mobile station MS.

FIG. 5 is a functional configuration diagram of the relay station in the present invention.

According to FIG. 5, the relay station 1 includes a wireless communication interface unit 101, a UL-MAP transfer unit 102, a range processing unit 103, a preamble determination unit 111, a seed information determination unit 112, and a range code transmission unit 113. And a preamble transmission unit 121 and a ranging code determination unit 122. These functional units can also be realized by a program that executes a computer mounted on the relay station 1.

The preamble determination unit 111 receives the preamble from the base station BS (or relay station RS), and the DL_PermBase that generated the preamble is the basic domain (0 to 31) or the relay domain (70, 80, ... ). The preamble determination unit 111 notifies the seed information determination unit 112 of the determination result.

When DL_PermBase is a basic domain (0 to 31), the seed information determination unit 112 determines seed information (for example, 70) that can be assigned as a relay station from the relay domain (70 to 127). On the other hand, when DL_PermBase is a relay domain (70, 80, ...), the seed information (for example, 75) that can be assigned is determined based on the seed information (70) for the relay station. The determined seed information is notified to the preamble transmission unit 121.

The preamble transmission unit 121 transmits the preamble generated by the seed information for the relay station. For example, send the preamble generated by DL_PermBase = 70 or 75.

The rangeing code determination unit 122 determines whether the initial range code received from the mobile station MS is a common code (for example, 127) or other than that. If it is a common code, the preamble transmitter 121 is notified to that effect. The preamble transmission unit 121 broadcasts the preamble generated by the seed information for the relay station (for example, 70). If the initial range code is other than the common code, the range code transmitter 113 is notified of the range code. The ranging code transmission unit 113 transfers the ranging code to the base station BS.

The UL-MAP transfer unit 102 receives the UL-MAP from the base station BS and transfers the UL-MAP to the mobile station MS.

The range processing unit 103 performs range processing, and transfers RNG-REQ / RNG-RSP between the base station BS and the mobile station MS.

FIG. 6 is a functional configuration diagram of the base station in the present invention.

According to FIG. 6, the base station 2 includes a wireless communication interface unit 201, a ranging code determination unit 202, a range processing unit 203, a relay route determination unit 204, a route table holding unit 205, and a bandwidth calculation unit 206. And a MAP scheduling unit 207 and a preamble transmission unit 208. These functional units can also be realized by a program that executes a computer mounted on the base station 2.

The rangeing code determination unit 202 determines whether the seed information that generated the received initial range code is the basic domain (0 to 69) or the relay domain (70 to 127). If it is a basic domain, that fact is notified to the range processing unit 203. If it is a relay domain, the relay route determination unit 204 is notified to that effect.

The relay route determination unit 204 identifies the relay station RS via which the mobile station MS passes, and determines the relay route. The route table holding unit 205 is referred to for determining the relay route. The route table holding unit 205 manages the topology of the entire network. The bandwidth calculation unit 206 allocates the bandwidth based on the relay route information. The MAP scheduling unit 207 updates the UL-MAP based on the bandwidth and transmits the UL-MAP.

The preamble transmission unit 208 transmits the preamble generated by DL_PermBase = 0 to 31.

FIG. 7 is a functional configuration diagram of the mobile station in the present invention.

According to FIG. 7, the mobile station 3 includes a wireless communication interface unit 301, a preamble determination unit 302, a range processing unit 303, a seed information determination unit 304, a range code generation unit 305, and a route table holding unit 306. Has. These functional units can also be realized by a program that executes a computer mounted on the mobile station 3.

The preamble determination unit 302 determines whether the seed information that generated the received preamble is the basic domain (0 to 31) or the relay domain (70 to 127). If it is a basic domain, the range processing unit 303 performs range processing on a normal base station BS.

When the seed information that generated the received preamble is a relay domain, the seed information determination unit 304 determines the seed information for the mobile station from the relay domain.

The rangeing code generation unit 305 generates an initial range code from the output of the PRBS generator using the determined seed information for the mobile station. The range processing unit 303 performs a range processing using this initial range code. Further, the generated range code is stored in the route table holding unit 306 in order to represent the route information. As a result, the network topology up to the base station BS is recognized.

According to the present invention, the range code used in the OFDMA method range processing is extended for a relay station. Such a range code assignment can be associated with a network topology that includes a relay station. The base station can identify the relay station through which the mobile station is passing, grasp the route of the entire network, and allocate the band based on the route information.

According to the various embodiments of the present invention described above, those skilled in the art can easily make various changes, modifications and omissions within the scope of the technical idea and viewpoint of the present invention. The above explanation is just an example and does not attempt to restrict anything. The present invention is limited only to the scope of claims and their equivalents.

<figref num="1">It is a block diagram of a PRBS generator which generates an OFDMA type range code.</figref><figref num="2">It is a network system block diagram in this invention.</figref><figref num="3">About the present invention, it is a ranging sequence via a relay station RS between a base station BS and a mobile station MS existing outside the service area.</figref><figref num="4">About the present invention, it is a ranging sequence via a relay station RS between a base station BS and a mobile station MS existing in the area thereof.</figref><figref num="5">It is a functional block diagram of the relay station in this invention.</figref><figref num="6">It is a functional block diagram of the base station in this invention.</figref><figref num="7">It is a functional block diagram of the mobile station in this invention.</figref>

Code description

1 Relay station 101 Wireless communication interface unit 102 UL-MAP transfer unit 103 Ranged processing unit 111 Preamble judgment unit 112 Seed information determination unit 113 Ranged code transmission unit 121 Preamble transmission unit 122 Ranged code determination unit 2 Base station 201 Wireless communication interface unit 202 Ranged code judgment unit 203 Rangeing processing unit 204 Relay route judgment unit 205 Route table holding unit 206 Bandwidth calculation unit 207 MAP scheduling unit 208 Preamble transmission unit 3 Mobile station 301 Wireless communication interface unit 302 Preamble processing unit 303 Rangeing processing unit 304 Seed information Determining part 305 Ranged code generation part 306 Route table holding part