JP4453486B2 - Radio channel relay method, radio communication system, and radio relay apparatus - Google Patents

Description

The present invention relates to a radio channel relay method , a radio communication system, and a radio relay apparatus used for a radio communication system such as a PHS (Personal Handy phone System).

  2. Description of the Related Art Conventionally, some wireless communication systems S such as PHS use a wireless relay device 3 having a relay function as shown in FIG. The wireless relay device 3 is installed when a wireless signal (for example, a control signal) from the base station 1 connected to a network (not shown) does not reach the mobile station 2 sufficiently. For example, a radio signal transmitted from the base station 1 installed outside the building 5 reaches the window 50a of the building 5 but reaches the mobile station 2 located at a location 51 away from the indoor window 50 of the building 5. If the radio relay apparatus 3 does not reach the target, the radio relay apparatus 3 is installed at the window 50a of the building 5 and relays the radio signal transmitted from the base station 1 to the mobile station 2 and is transmitted from the mobile station 2. The received radio signal is relayed and transmitted to the base station 1. As a result, communication can be performed between the base station 1 and the mobile station 2.

  At this time, the radio relay apparatus 3 establishes a communication channel with the mobile station 2 after establishing a communication channel with the base station 1. At that time, a communication channel with the mobile station 2 may be assigned to a reception time slot (hereinafter referred to as “reception slot”) 41a (see FIG. 6) to which the control channel with the mobile station 2 has been assigned. . For example, when the wireless relay device 3 has a function of providing relay processing to two mobile stations 2 (only one is shown in FIG. 2) at the same time, a communication channel with one mobile station 2 is relaying In this state, when the relay process with the other mobile station 2 is started, the communication channel with the other mobile station 2 must be assigned to the reception slot 41a to which the control channel has been assigned.

  In order to perform the above operation, the recent radio relay apparatus 3 communicates with the control channel with the mobile station 2 in the reception slot 41a to which the control channel with the mobile station 2 has been assigned, as shown in FIG. Means for switching and allocating channels are provided. The slot configuration of the mobile station 2 is shown in FIG.

  For example, in the reception slot 41a, the radio relay device 3 (see FIG. 2) sets the reception timing of the mobile station 2 (see FIG. 2) one time out of the total 20 reception timings. In the case of operating in accordance with a rule in which the remaining 19 times are set to a timing for receiving and receiving a communication channel with the mobile station 2, a process for receiving and receiving a control channel with the mobile station 2, and a communication channel with the mobile station 2 It is operated while switching between the process of waiting for and receiving.

  After receiving from the mobile station 2 a request signal (request message) for establishing a communication channel with the mobile station 2 (see FIG. 2), the control unit of the wireless relay device 3 (see FIG. 2) 1 (see FIG. 2) is established (see t1 to t4 in FIG. 4). After that, as shown in FIG. 7, an allocation signal for establishing a communication channel with the mobile station 2 is transmitted to the mobile station 2 (t1 in FIG. 7). After assigning the control channel with the mobile station 2 to the reception slot 41a (see FIG. 6) (t2), the control channel is switched to the communication channel with the mobile station 2 and assigned (t3). A process of receiving and receiving a signal of a communication channel such as a synchronous burst signal is performed (t4), and when a control channel with the mobile station 2 is assigned again to the receiving slot 41a (t6), a communication channel with the mobile station 2 A process of waiting for and receiving a control channel signal such as a re-request signal (re-request message) for establishing (t7).

  Next, in the wireless relay device 3 (see FIG. 2), after establishing a communication channel with the base station 1 (see FIG. 2), an operation for establishing a communication channel with the mobile station 2 (see FIG. 2) Will be described with reference to FIG. First, a case where a synchronization burst signal is received from the mobile station 2 within a predetermined time will be described. First, a request signal transmitted from the mobile station 2 for establishing a communication channel with the mobile station 2 is received in a reception slot 41a (see FIG. 6) to which a control channel with the mobile station 2 is assigned. After that, a communication channel with the base station 1 is established. Next, an allocation signal for establishing a communication channel with the mobile station 2 is transmitted to the mobile station 2 (S1 in FIG. 8). After transmitting the allocation signal, a timer (not shown) is started, and the time after transmitting the allocation signal, that is, the waiting time of the synchronous burst signal from the mobile station 2 is measured (S2). It is within a predetermined time set by the timer (S3), and when it is time to receive a signal of a communication channel with the mobile station 2 (S4), the reception channel to which the control channel with the mobile station 2 is assigned The slot 41a is switched so as to allocate a communication channel with the mobile station 2, and a processing state for receiving a signal of the communication channel is set (S5). Here, it repeatedly tries to receive the synchronous burst signal from the mobile station 2 in the receiving slot 41a (S6). After receiving the synchronization burst signal, the synchronization burst signal is transmitted to the mobile station 2, the TCH burst signal is transmitted to the mobile station 2, and the TCH burst signal is received from the mobile station 2 (S7). As a result, the wireless relay device 3 establishes a communication channel with the mobile station 2.

  On the other hand, the case where a synchronous burst signal is not received from the mobile station 2 (see FIG. 2) within a predetermined time will be described. First, the operations (S1) to (S6) are performed. If the synchronization burst signal from the mobile station 2 is not received in the reception slot 41a (see FIG. 6), the operation from (S3) is performed again. When it is time to receive a control channel signal with the mobile station 2 (S4), the process switches to a processing state for receiving the control channel signal (S8), and a re-request signal for establishing a communication channel with the mobile station 2 is received. It is received from the mobile station 2 (S9), and it is determined whether or not the number of reassignments is less than or equal to a specified value (S10). If it is below the specified value, a reassignment signal for establishing a communication channel with the mobile station 2 is transmitted to the mobile station 2 (S11), and the operation from the above (S2) is performed again. If the specified value is exceeded, the process for establishing a communication channel with the mobile station 2 is stopped (S12). Further, when the synchronization burst signal is not received from the mobile station 2 within a predetermined time after the start of the measurement by the timer (S3), the operation from the above (S10) is performed.

In Patent Document 1, the first communication channel assigned between the radio base station and the radio relay device is selected, and transmitted from the assigned first communication channel and the radio base station. By determining the communication channel assigned to the wireless terminal from the control channel, the second communication channel assigned from the wireless base station is prevented from being equal to the first communication channel assigned to the wireless terminal, and the call loss rate is reduced. A wireless communication system, a wireless channel assignment method, and a wireless relay device are disclosed.
JP 2001-53673 A (pages 4 to 7 and FIGS. 1 and 2)

  However, the above-described conventional wireless relay device and the like require both a process for receiving and receiving a control channel signal with a mobile station and a process for receiving and receiving a communication channel signal with a mobile station. There is a problem that the processing becomes complicated, and it takes time to implement the reception processing and verify the operation.

The present invention has been made in view of the above points, and the object of the present invention is to realize simplification of reception processing and increase efficiency of implementation of reception processing and operation verification. A wireless channel relay method , a wireless communication system, and a wireless relay device are provided.

The radio channel relay method according to claim 1 divides a plurality of slots obtained by time-dividing one frame having a predetermined time length into a reception slot and a transmission slot, and a control channel or a communication channel is assigned to the slot. Assigning a radio signal transmitted from one of the base station or mobile station using a radio relay device provided in a radio communication system that performs radio communication between a base station and a mobile station connected to the network the continuously linear channel repeater how to relay to the other, the mobile station transmits a request signal for requesting the establishment of a communication channel between the mobile station radio relay apparatus to the radio relay device The radio relay apparatus establishes the communication channel after receiving the request signal in a state where the control channel is allocated to the reception slot for the mobile station. An allocation signal is transmitted to the mobile station, and the mobile station transmits the synchronization burst signal from the mobile station to the radio relay apparatus until receiving the synchronization burst signal from the radio relay apparatus after receiving the allocation signal. If a synchronization burst signal is not received from the radio relay apparatus even after a preset period has elapsed, a re-request signal for re-requesting establishment of the communication channel is transmitted to the radio relay apparatus, and the radio relay device, wherein after transmitting an assignment signal, to assign to fix the communications channel to the reception slots of the control channel the mobile station for which has been assigned, the the reception slot of the mobile station's the synchronization burst signal from the mobile station repeatedly attempt to receive the or the mobile station in the predetermined time in a state in which a communication channel has always assigned If the did not receive a synchronization burst signal, transmitting continuously the allocation of the communication channel to the reception slots of the mobile station for a reallocation signal to establish said communication channel to said mobile station It is characterized by.

  In this configuration, it is not necessary to sequentially switch the process for receiving the control channel and the process for receiving the communication channel in accordance with the operation of the mobile station in the reception slot for the mobile station, thereby simplifying the reception process. It is possible to improve the efficiency of implementation of reception processing and operation verification.

The wireless communication system according to claim 2 divides a plurality of slots obtained by time-dividing one frame having a predetermined time length into reception slots and transmission slots, and assigns a control channel or a communication channel to the slots. A wireless communication system for performing wireless communication between a base station and a mobile station connected to a network via a wireless relay device that relays a wireless signal transmitted from one of the base station or the mobile station to the other The mobile station has received a function for transmitting a request signal for requesting establishment of a communication channel between the mobile station and the radio relay apparatus to the radio relay apparatus, and the allocation signal. After that, a function of transmitting the synchronization burst signal from the mobile station to the radio relay apparatus until a synchronization burst signal from the radio relay apparatus is received, and a preset period have elapsed. A function of transmitting a re-request signal for re-requesting establishment of the communication channel to the wireless relay device when the synchronization burst signal from the wireless relay device is not received, Receiving means for receiving the request signal in a state where the control channel is assigned to a receiving slot for a station, and an assignment signal for establishing the communication channel after the request signal is received by the receiving means. transmission means for transmitting to the mobile station, after transmitting the assignment signal, and an allocation means for allocating secure the communication channel to the reception slots of the mobile station for which the control channel is assigned, the reception means receives a synchronization burst signal from the mobile station to the communication channel to the reception slots of the mobile station for always assigned state DOO repeatedly attempted, the allocation unit, when the not received a synchronization burst signal from the mobile station within a predetermined time, the allocation of the communication channel to the receiving slot of the mobile station's continuously, and the transmission unit, when the not received a synchronization burst signal from the mobile station within a predetermined time, and transmits the re-assignment signal for establishing said communication channel to said mobile station It is characterized by that.

In this configuration, it is not necessary to sequentially switch the process for receiving the control channel and the process for receiving the communication channel in accordance with the operation of the mobile station in the reception slot for the mobile station, thereby simplifying the reception process. It is possible to improve the efficiency of implementation of reception processing and operation verification.
The invention of the wireless relay device according to claim 3 is used in the wireless communication system according to claim 2.

  According to the present invention, simplification of reception processing can be realized, and the efficiency of implementation of reception processing and operation verification can be improved.

  Embodiments in which the present invention is applied to a wireless relay device (relay station) used in a wireless communication system compliant with the second generation cordless telephone system standard (RCR STD-28 4.0 version, issued by the Japan Radio Industry Association) Will be described. However, the configurations and operations of the base station and the mobile station and the basic operation of the radio relay apparatus are well known in the art as defined in the above-mentioned standard, and thus description thereof is omitted.

  The radio communication system S of the present embodiment is, for example, a PHS using a radio frequency of 1.9 GHz band, and includes a base station 1, a mobile station 2, and a radio relay device 3 as shown in FIG. Wireless communication is performed between the base station 1 and the mobile station 2 via the wireless relay device 3.

  As an example of the wireless communication system, there is a 4-channel multiplexed TDMA-TDD (Time Division Multiple Access-Time Division Duplex) system, for example. In the present embodiment, the TDMA-TDD method is used. In the TDMA-TDD system, as shown in FIG. 3, a frame 4 having a predetermined time length (for example, 5 msec) is set as one unit of a radio signal, and the frame 4 is time-divided into 8 equal parts. Slots (time length 0.625 msec) 40... 41. Of the eight slots 40... 41 in the frame 4, four slots are divided into transmission slots 40... And the remaining four slots are divided into reception slots 41. A control channel or a communication channel is assigned to the slots 40. In this embodiment, of the transmission slots 40..., 40 a is a transmission slot to which a control channel with the mobile station 2 is assigned, and among the reception slots 41... 41 a is a control channel with the mobile station 2. The assigned reception slot.

  Each slot 40..., 41... Contains 160 bit data, and is between the base station 1 (see FIG. 2) and the radio relay device 3 (see FIG. 2), and between the radio relay device 3 and the mobile station 2 (FIG. 2). Since the 160-bit data is transmitted in half duplex every 5 msec, a communication speed of 32 kbit / sec can be obtained per unit time. In this embodiment, when one frame 4 has a period of 20 msec and one frame 4 has a time length of 5 msec, one period is 100 msec.

  In the PHS employing the TDMA-TDD system, a large number of frequency channels (frequency carriers) set every 300 kHz in the range of 188.650 MHz to 1919.450 MHz are multiplexed every four slots. Of these, a specific frequency channel is assigned to each communication carrier for a control channel having the purpose of transferring control information necessary for connection, and communication for the purpose of transferring user information to other frequency channels. Assigned to the channel.

  As shown in FIG. 2, the base station 1 is installed outside the building 5, and is connected to, for example, another base station, a public telephone network, and a network unique to a communication carrier (all not shown). Further, the mobile station 2 is, for example, a PHS terminal, is located at a location 51 away from the indoor window 50 of the building 5, and wirelessly transmits a request signal or a re-request signal for establishing a communication channel with the wireless relay device 3. It transmits to the relay apparatus 3 (t1, t8 in FIG. 4).

  As shown in FIG. 1, the wireless relay device 3 includes antennas 30 and 31, wireless circuits 32 and 33, baseband circuits 34 and 35, and a control unit 36. As shown in FIG. The radio signal transmitted from the base station 1 is relayed and transmitted to the mobile station 2, and the radio signal transmitted from the mobile station 2 is relayed and transmitted to the base station 1. Thereby, communication can be performed between the base station 1 installed outside the building 5 and the mobile station 2 located in the location 51 away from the indoor window 50 of the building 5.

  As shown in FIG. 1, the antenna 30 is connected to the radio circuit 32, and transmits and receives radio signals (radio wave signals) to and from the base station 1 (see FIG. 2). The radio circuit 32 is connected to the antenna 30 and the baseband circuit 34, converts a high frequency signal based on the radio signal received by the antenna 30 into a baseband signal, outputs the baseband signal to the baseband circuit 34, and The baseband signal input from the baseband circuit 34 is converted into a high frequency signal, and the high frequency signal is transmitted from the antenna 30 to the base station 1 as a radio signal. The baseband circuit 34 is connected to the radio circuit 32 and the control unit 36 and controls transmission / reception of voice signals and control signals on the radio line to the base station 1 according to the TDMA-TDD system.

  On the other hand, the antenna 31 is connected to the radio circuit 33 and transmits / receives a radio signal to / from the mobile station 2 (see FIG. 2). The radio circuit 33 is connected to the antenna 31 and the baseband circuit 35, converts a high frequency signal based on the radio signal received by the antenna 31 into a baseband signal, and outputs the baseband signal to the baseband circuit 35. The baseband signal input from the baseband circuit 35 is converted into a high frequency signal, and the high frequency signal is transmitted from the antenna 31 to the mobile station 2 as a radio signal. The baseband circuit 35 is connected to the radio circuit 33 and the control unit 36, and controls transmission / reception of voice signals and control signals on the radio channel to the mobile station 2 according to the TDMA-TDD system.

  The control unit 36 includes a CPU, a memory, a timer (not shown), and the like. The control unit 36 is connected to the baseband circuits 34 and 35, and the program stored in the memory is executed by the CPU. Performs overall control.

  The control unit 36 receives the request signal transmitted from the mobile station 2 (see FIG. 2) for establishing a communication channel with the mobile station 2 in the reception slot 41a (see FIG. 3) (see FIG. 4). t1). After receiving the request signal, a communication channel with the base station 1 (see FIG. 2) is established (t2 to t4 in FIG. 4). Thereafter, an allocation signal for establishing a communication channel with the mobile station 2 is transmitted to the mobile station 2 via the radio circuit 33 and the antenna 31 (t5). After transmitting the allocation signal, a timer (not shown) measures the time after transmitting the allocation signal.

  After transmitting the assignment signal, the control unit 36 assigns the communication channel with the mobile station 2 in a fixed manner to the reception slot 41a (see FIG. 3) to which the control channel with the mobile station 2 (see FIG. 2) has been assigned. Thus, it repeatedly tries to receive the synchronous burst signal from the mobile station 2 in the reception slot 41a (t6 in FIG. 4). During this time, the process of consistently receiving the communication channel signal is performed at the timing of receiving the communication channel signal with the mobile station 2 or at the timing of receiving the control channel signal with the mobile station 2. Do. This eliminates the need to dynamically switch between the process of receiving a communication channel signal and the process of receiving a control channel signal at each reception timing.

  In this way, for example, out of a total of 20 reception timings, one time is set as a timing for receiving and receiving a control channel with the mobile station 2 (see FIG. 2), and the remaining 19 times are set as communication channels with the mobile station 2. Even when the control unit 36 is operating according to the rule of waiting for and receiving, the control unit 36 waits for the control channel with the mobile station 2 and receives the control channel with the mobile station 2 and waits for the communication channel with the mobile station 2. It is not necessary to operate the receiving process while sequentially switching channels in accordance with the operation of the mobile station 2.

  When the control unit 36 receives a synchronization burst signal from the mobile station 2 (see FIG. 2) within a predetermined time (for example, 200 msec) after the timer (not shown) starts measurement, the control unit 36 receives the TCH burst. A signal is transmitted to the mobile station 2 to establish a communication channel with the mobile station 2 (t11 and t12 in FIG. 4). On the other hand, if the synchronization burst signal is not received within the predetermined time (t9), a reassignment signal for establishing a communication channel with the mobile station 2 is transmitted to the mobile station 2. (T10).

  Next, an operation for establishing a communication channel with the mobile station 2 (see FIG. 2) in the wireless relay device 3 of the present embodiment will be described with reference to FIG. First, a case where a synchronization burst signal is received from the mobile station 2 within a predetermined time will be described. First, a request signal transmitted from the mobile station 2 for establishing a communication channel with the mobile station 2 is received in a reception slot 41a (see FIG. 3) to which a control channel with the mobile station 2 is assigned. After that, a communication channel with the base station 1 (see FIG. 2) is established (see FIG. 4). Next, an allocation signal for establishing a communication channel with the mobile station 2 is transmitted to the mobile station 2 (S1 in FIG. 5). After transmitting the assignment signal, switching is performed so that the communication channel with the mobile station 2 is fixedly assigned to the receiving slot 41a to which the control channel with the mobile station 2 is assigned, and a timer (not shown) is started. Then, the time after transmitting the allocation signal, that is, the waiting time of the synchronous burst signal from the mobile station 2 is measured (S2). Within a predetermined time set by the timer (S3), when it is time to receive a communication channel signal with the mobile station 2 (S4), a processing state for receiving the communication channel signal is entered (S5). . Here, it repeatedly tries to receive the synchronous burst signal from the mobile station 2 in the receiving slot 41a (S6). After receiving the synchronization burst signal, the synchronization burst signal is transmitted to the mobile station 2, the TCH burst signal is transmitted to the mobile station 2, and the TCH burst signal is received from the mobile station 2 (S7). Thereby, the radio relay apparatus 3 establishes a communication channel with the mobile station 2 after establishing a communication channel with the base station 1.

  On the other hand, the case where a synchronous burst signal is not received from the mobile station 2 (see FIG. 2) within a predetermined time will be described. First, the operations (S1) to (S6) are performed. If the synchronization burst signal from the mobile station 2 is not received in the reception slot 41a (see FIG. 3), the operation from (S3) is performed again. Even when it is time to receive the control channel signal with the mobile station 2 (S4), the processing state of receiving the communication channel signal is continued (S8), resulting in a reception error (S9). Further, when a synchronization burst signal is not received from the mobile station 2 within a predetermined time after the start of measurement by the timer (S3), it is determined whether or not the number of reassignments is equal to or less than a specified value (S10). ). If it is below the specified value, a reassignment signal for establishing a communication channel with the mobile station 2 is transmitted to the mobile station 2 (S11), and the operation from the above (S2) is performed again. If the specified value is exceeded, the process for establishing a communication channel with the mobile station 2 is stopped (S12).

  From the above, when the communication channel with the mobile station 2 (see FIG. 2) is fixedly assigned to the receiving slot 41a (see FIG. 3) to which the control channel with the mobile station 2 has been assigned, the mobile station 2 If the synchronization burst signal is not received, a reassignment signal for establishing a communication channel with the mobile station 2 is transmitted to the mobile station 2, so that only the synchronization burst signal is targeted at the reception timing from the mobile station 2. What is necessary is just to process.

  As described above, according to the present embodiment, the communication channel with the mobile station 2 is fixedly assigned to the reception slot 41a to which the control channel with the mobile station 2 has been assigned. Is not required to be sequentially switched in accordance with the operation of the mobile station 2, thereby simplifying the reception process and improving the efficiency of implementation of the reception process and operation verification. it can.

It is a block diagram of the radio relay device of an embodiment by the present invention. It is a block diagram of a radio | wireless communications system same as the above. It is a slot block diagram for demonstrating operation | movement of a radio relay apparatus same as the above. It is a sequence diagram for demonstrating operation | movement of a radio relay apparatus same as the above. It is a flowchart for demonstrating operation | movement of a radio relay apparatus same as the above. It is a block diagram for explaining the operation of a conventional wireless relay device. It is a sequence diagram for demonstrating operation | movement of a radio relay apparatus same as the above. It is a flowchart for demonstrating operation | movement of a radio relay apparatus same as the above.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Base station 2 Mobile station 3 Radio relay apparatus 30, 31 Antenna 32, 33 Radio circuit 34, 35 Baseband circuit 36 Control part 41 Slot S for reception Wireless communication system

Claims (3)

A plurality of slots obtained by time-dividing one frame having a predetermined time length are divided into reception slots and transmission slots, and a control channel or a communication channel is allocated to the slots, and a base station and a mobile station connected to the network using the wireless relay apparatus provided in a radio communication system that performs radio communication with a radio signal transmitted from one of the base station or mobile station to a non-linear channel repeater how to relay to the other,
The mobile station transmits a request signal for requesting establishment of a communication channel between the mobile station and the wireless relay device to the wireless relay device;
The radio relay apparatus receives the request signal in a state where the control channel is allocated to a reception slot for the mobile station, and then transmits an allocation signal for establishing the communication channel to the mobile station,
The mobile station transmits the synchronization burst signal from the mobile station to the radio relay apparatus until receiving the synchronization burst signal from the radio relay apparatus after receiving the allocation signal, and a preset period has elapsed. If a synchronization burst signal is not received from the wireless relay device, a re-request signal for re-requesting establishment of the communication channel is transmitted to the wireless relay device,
The radio relay apparatus, after transmitting the allocation signal, the control channel allocates fixed the communication channel to the reception slots of the mobile station for which has been assigned, the reception slot of the mobile station's the synchronization burst signal from the mobile station repeatedly attempt to receive the, if the not received a synchronization burst signal from the mobile station within a predetermined time in a state in which the communication channel has always assigned to The radio channel relay method characterized by continuing the allocation of the communication channel to the reception slot for the mobile station and transmitting a reassignment signal for establishing the communication channel to the mobile station. A plurality of slots obtained by time-dividing one frame having a predetermined time length are divided into reception slots and transmission slots, and a control channel or a communication channel is allocated to the slots, and a base station and a mobile station connected to the network between a radio communication system that performs radio communication via the radio relay device that relays a radio signal transmitted from one of the base station or the mobile station to the other,
The mobile station
A function of transmitting a request signal for requesting establishment of a communication channel between the mobile station and the wireless relay device to the wireless relay device;
A function of transmitting the synchronization burst signal from the mobile station to the wireless relay device until receiving the synchronization burst signal from the wireless relay device after receiving the allocation signal;
A function of transmitting a re-request signal for re-requesting establishment of the communication channel to the wireless relay device when a synchronization burst signal from the wireless relay device is not received even after a preset period has elapsed; And
The wireless relay device is
Receiving means for receiving the request signal in a state in which the control channel is assigned to the receiving slot for the mobile station;
Transmitting means for transmitting an allocation signal for establishing the communication channel to the mobile station after the request signal is received by the receiving means;
After sending the assignment signal, and an allocation means for allocating secure the communication channel to the reception slots of the mobile station for which the control channel is assigned,
It said receiving means repeatedly attempt to receive the sync burst signal from the mobile station to the communication channel to the reception slots of the mobile station for always assigned state,
The allocating unit continues allocating the communication channel to the receiving slot for the mobile station when the synchronization burst signal from the mobile station is not received within the predetermined time,
The transmission unit, characterized in that the transmission if the did not receive a synchronization burst signal from the mobile station within a predetermined time, the re-allocation signal for establishing said communication channel to said mobile station A wireless communication system . A wireless relay device used in the wireless communication system according to claim 2.

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