JP2009153022A - Communication system, base station device, mobile station device, and communication method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent transmission timing from becoming unknown, when shifting to a communication channel, because of the difference between a communication mode of a control channel and the communication mode of a communication channel, in a mobile communication system. <P>SOLUTION: The communication system comprises a plurality of mobile stations 11; and a base station 12 that relays communication between mobile stations and manages a transmission right of each of the mobile stations. In the communication system, the transmission right is requested and imparted by random access via a control channel at a first transmission rate, and the communication between the mobile stations is performed via a communication channel at a second transmission rate. Each of the mobile stations transmits a frame, requesting the transmission right via the control channel and in response to the frame, the base station transmits a frame permitting the request to the mobile station, and the communication system comprises a timing correction means for correcting the transmission timing of the frame to be proper timing on the communication channel, when the mobile station starts transmitting the frame via the communication channel, in response to the permission frame. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a communication system including a plurality of mobile stations and a base station that relays communication between the mobile stations and manages transmission rights of the mobile stations, and a base station apparatus and a mobile suitable for the communication system The present invention relates to a station apparatus and a communication method.

  Conventionally, as a mobile communication system, a base station and a plurality of mobile stations are provided as in a trunked system, and the mobile station uses a technique called random access, acquires a transmission right from the base station via a control channel, and sets a communication channel. There are known devices that perform communication via the network (see, for example, Patent Document 1 and Patent Document 2). Communication between each mobile station and base station is performed by transmitting and receiving wirelessly while synchronizing a predetermined frame.

  FIGS. 3A and 3B show a configuration example of such a conventional mobile communication system. As shown in the figure, this mobile communication system includes a plurality of mobile stations 31 and a base station 32 that relays communication between the mobile stations 31 and manages the transmission right of each mobile station 31. Communication between the mobile station 31 and the base station 32 is performed at a transmission rate of 4800 [bps] as shown in FIG. 4A, or at a transmission rate of 9600 [bps] as shown in FIG. Is called.

  FIGS. 5A and 5B show frame timings during random access in the mobile communication system of FIG. FIG. 5A shows the timing when communication is performed in a communication mode with a transmission rate of 4800 [bps] as shown in FIG. 3A. FIG. 5B shows the timing in FIG. As shown, the timing when communication is performed in a communication mode with a transmission rate of 9600 [bps] is shown. In the 4800 [bps] communication mode, the length of each frame is 80 [ms], and in the 9600 [bps] communication mode, the length of each frame is 40 [ms].

  In the case of FIG. 5A, in the control channel, the mobile station 31 receives the frame 55 transmitted by the base station 32 at a transmission rate of 4800 [bps], and confirms that transmission by random access is possible. In order to perform random access, a frame 56 requesting a transmission right is transmitted 40 [ms] after the end of the frame section of the frame 55. In response to this, when receiving the frame 57 permitting the request to be transmitted by the base station 32 40 [ms] after the end of the frame 56, the mobile station 31 starts communication on the communication channel. The frame 58 is transmitted 40 [ms] after the section of the frame 57 ends. In this way, the mobile station 31 can acquire the transmission right from the base station 32 and perform transmission by random access. In the case of FIG. 5B as well, communication is started by random access in the same manner except that each frame section is 40 [ms].

  As described above, in each of the same sites shown in FIGS. 3A and 3B, both the control channel and the communication channel are generally used in the same communication mode (transmission speed).

JP 2006-93869 A JP 2006-174142 A

  Here, assume base stations having different communication modes (transmission speeds) in the same site. That is, two communication modes are mixed and the communication mode on the control channel and the communication mode on the communication channel are different. In this case, since the communication modes are different, the transmission timing on the control channel and the transmission timing on the communication channel in the mobile station may be different depending on the frame length and transmission / reception timing of each communication mode. For this reason, a communication system in which two communication modes are mixed cannot be simply configured.

  FIGS. 1A and 1B show a configuration example of a mobile communication system which can be considered as a case where communication is performed in different communication modes in a control channel and a communication channel. As shown in the figure, this system includes a plurality of mobile stations 11 and a base station 12 that relays communication between the mobile stations 11 and manages transmission rights of the mobile stations 11.

  In this example, a communication mode with a transmission rate of 4800 [bps] and a communication mode with a transmission rate of 9600 [bps] coexist at one site. The timing at the time of random access in such a case is the reverse of the case where random access is performed on the 4800 [bps] control channel and communication is performed on the 9600 [bps] communication channel as shown in FIG. As shown in FIG. 5B, there may be a case where random access is performed on the control channel of 9600 [bps] and communication is performed on the communication channel of 4800 [bps].

  FIG. 4A shows the frame timing during random access in the case of the configuration shown in FIG. 4 (b) and 4 (c) show frame timings during random access in the case of the configuration of FIG. 1 (b). In the 4800 [bps] communication mode, one frame is 80 [ms], and in the 9600 [bps] communication mode, one frame is 40 [ms].

  At the timing of FIG. 4A, random access is performed at 4800 [bps] on the control channel, and communication is performed at 9600 [bps] on the communication channel. That is, paying attention to the operation of the mobile station 11, when the mobile station 11 makes a call for communication, the base station 12 receives the frame 41 of 4800 [bps] transmitted on the control channel, and is transmitted by random access. After confirming that the transmission right is possible, the frame 42 requesting the transmission right is transmitted by random access after 40 [ms]. Upon receiving this frame 42, the base station 12 transmits a frame 43 indicating which communication channel is permitted to communicate at the next frame timing. When this frame 43 is received, the mobile station 11 shifts to the communication channel specified by the frame 43 and transmits after 40 [ms].

  In this case, the timing at which the random access is performed does not change the timing at which the control channel is changed to the communication channel and transmission is started. Therefore, the transmission timing in the communication channel of the mobile station 11 maintains the timing in the control channel, so that different communication modes can coexist.

  On the other hand, at the timings of FIGS. 4B and 4C, random access is performed at 9600 [bps] on the control channel, and communication is performed at 4800 [bps] on the communication channel. That is, paying attention to the operation of the mobile station 11, first, at the timing shown in FIG. 4B, when the mobile station 11 transmits for communication, a frame is received on the control channel of 9600 [bps]. . Since this frame is a 40 [ms] frame, two frames are arranged for the frame section of the 80 [ms] frame 45 of the communication channel. When the latter half portion 46 of the frames of the two control channels is received and it is confirmed that transmission by random access is possible, the mobile station 11 requests the transmission right by random access after 47 [ms]. Send. When this frame 47 is received, the base station 12 transmits a frame 48 indicating which communication channel is permitted to communicate at the next frame timing. When this frame 48 is received, the mobile station 11 shifts to the communication channel specified by the frame 48 and transmits the frame 49 after 40 [ms].

  In this case, even if the control channel shifts to the communication channel, the transmission timing does not change before and after the shift. That is, the transmission timing in the communication channel of the mobile station 11 maintains the timing in the control channel. Therefore, in this case, there is no problem due to the coexistence of different communication modes.

  At the timing shown in FIG. 4C, when the mobile station 11 makes a call for communication, a frame is received on a control channel of 9600 [bps]. Since the received frame is a 40 [ms] frame, two frames are arranged for the 80 [ms] frame 50 of the communication channel. When the first half portion 51 of the two control channel frames is received and it is confirmed that transmission by random access is possible, the mobile station 11 requests a transmission right by random access after 40 [ms]. 52 is transmitted. Upon receiving this frame 52, the base station 12 transmits a frame 53 indicating which communication channel is permitted to communicate at the next frame timing. Upon receiving this frame 53, the mobile station 11 moves to the communication channel designated by the frame 53, and transmits the frame 54 after 80 [ms] so as to match the transmission timing in the communication channel. In this case, when the control channel shifts to the communication channel, the transmission timing differs before and after the shift.

  As described above, FIGS. 4B and 4C show that the frame transmission timing differs when the mobile station 11 shifts from the control channel to the communication channel according to the random access timing. . However, since the mobile station 11 does not know whether the timing of transmitting the frame requesting the transmission right is the timing of FIG. 4B or 4C, the transmission timing of the frame when the mobile station 11 shifts to the communication channel is determined. It cannot be recognized.

  As described above, when the random access is performed at 9600 [bps] on the control channel and the communication is performed at 4800 [bps] on the communication channel, the mobile station 11 indicates the timing at which the mobile station 11 transmits the frame requesting the transmission right. Since it is not known whether the timing is 4 (b) or (c), there is a problem in that it is impossible to determine the transmission timing when shifting to the communication channel.

  The object of the present invention is to solve the above-mentioned problems of the prior art, in the mobile communication system, when the communication mode of the control channel and the communication mode of the communication channel are different, and when the transition to the communication channel occurs. This is to prevent the transmission timing from becoming unknown.

  A first invention for achieving this object includes a plurality of mobile stations and a base station that relays communication between the mobile stations and manages transmission rights of the mobile stations. The communication between the two is performed by wirelessly transmitting and receiving a predetermined frame via the control channel based on the first transmission rate and the communication channel based on the second transmission rate. The present invention relates to a communication system which is performed by random access through a control channel, and communication between each mobile station is performed through the communication channel. Then, each mobile station transmits a frame requesting the transmission right via the control channel, and in response, the base station transmits a frame permitting the request to the mobile station. When the mobile station starts transmission of a frame via the communication channel, the mobile station includes timing correction means for correcting the transmission timing of the frame so as to be an appropriate timing in the communication channel. . Here, the communication system corresponds to, for example, a trunked system.

  In this configuration, since the transmission rates of the control channel and the communication channel are different, a plurality of frames of the control channel may correspond to one frame section in the communication channel. In this case, when performing random access through the control channel, the mobile station requests a transmission right, and the base station permits the frame timing to have multiple types of timing relative to the frame timing in the communication channel. It will be going. When performing random access, the mobile station only needs to transmit a frame requesting a transmission right in synchronization with the timing of the frame in the control channel. Therefore, the mobile station transmits at any timing among the plurality of types of timings. There is no way in the prior art to know if a frame requesting a right has been transmitted. Therefore, if the communication channel is shifted to and frame transmission is simply started at a certain timing, the transmission timing may not match the proper transmission timing. However, according to the present invention, there is provided timing correction means for correcting the transmission timing of the frame so as to be an appropriate timing in the communication channel. Therefore, after shifting to the communication channel, the frame is transmitted at an appropriate timing. It can be carried out.

  The base station apparatus according to the second aspect of the invention is a wireless communication that transmits and receives a predetermined frame in synchronization with a plurality of mobile stations via a control channel at a first transmission rate and a communication channel at a second transmission rate. Means for managing transmission rights of each mobile station via the control channel and relaying communication between the mobile stations via the communication channel, wherein the transmission right by random access is granted. The requested frame is received from each mobile station via the control channel, and in response to this, the request grant frame is transmitted to the mobile station when possible, and the request frame is received at that time. Based on the timing, the mobile station includes information on the timing at which the mobile station should start transmission of a frame in the communication channel. That.

  A mobile station apparatus according to a third aspect of the present invention is a wireless communication that transmits and receives a predetermined frame in synchronization with a predetermined base station via a control channel based on a first transmission rate and a communication channel based on a second transmission rate. Means for acquiring a transmission right from the base station via the control channel and relaying communication with another mobile station via the communication channel by the base station. A frame requesting the transmission right by random access is transmitted to the base station via the control channel, and a frame permitting the request transmitted by the base station in response thereto is received, and then the permission is transmitted. Frame transmission on the communication channel can be performed at a timing based on information on frame transmission timing on the communication channel included in the frame. The features.

  A mobile station apparatus according to a fourth invention is characterized in that, in the second or third invention, the first transmission rate is an integral multiple of the second transmission rate.

  An apparatus according to a fifth invention is characterized in that, in the fourth invention, the information on the transmission timing is information indicating a position in the frame section of the communication channel where the request frame is arranged. .

  A mobile station apparatus according to a sixth aspect of the invention is a wireless communication that transmits and receives a predetermined frame in synchronization with a predetermined base station via a control channel at a first transmission rate and a communication channel at a second transmission rate. Means for acquiring a transmission right from the base station via the control channel and relaying communication with another mobile station via the communication channel by the base station. The first transmission rate is an integral multiple of the second transmission rate, the frame of the control channel constitutes a super frame, and the number of frames constituting the super frame is an integral multiple of the integer. Each time the station apparatus receives each frame constituting the super frame, the station apparatus counts the order of each frame in the super frame, and the mobile station apparatus Transmitting a frame requesting the transmission right by random access to the base station via the control channel, receiving a frame permitting the request transmitted by the base station in response thereto, and then receiving the super frame Based on the count value, the frame transmission timing in the communication channel is recognized, and the frame transmission in the communication channel is performed at the timing.

  A communication method according to a seventh invention comprises a plurality of mobile stations and a base station that relays communication between the mobile stations and manages the transmission right of each mobile station, and communicates between each mobile station and the base station. Is performed by wirelessly transmitting and receiving a predetermined frame via a control channel based on the first transmission rate and a communication channel based on the second transmission rate, and the transmission right request and grant are performed on the control channel. Is a communication method in a communication system in which communication between mobile stations is performed through the communication channel, and each mobile station transmits a frame requesting the transmission right through the control channel. In response, the base station transmits a frame permitting the request to the mobile station, and in response, the mobile station starts transmitting a frame via the communication channel. To the transmission timing of the frame, and correcting so that a proper timing in the communication channel.

  According to the present invention, the timing correction means for correcting the transmission timing of the frame after shifting to the communication channel so as to be an appropriate timing in the communication channel is provided, so that the communication mode of the control channel and the communication channel is provided. Therefore, it is possible to prevent the transmission timing at the time of shifting to the communication channel from becoming unknown, and to transmit the frame at an appropriate timing after shifting to the communication channel.

  1A and 1B each show a mobile communication system according to an embodiment of the present invention. As shown in the figure, this communication system includes a plurality of mobile stations 11 that move in association with a vehicle or a worker, and control information that enables each mobile station 11 to share a predetermined number of radio channels. A base station 12 that transmits to each mobile station 11 and manages each mobile station 11 is provided. The base station 12 relays communication between the mobile stations 11 and manages the transmission rights of the mobile stations 11. Each mobile station 11 and base station 12 performs communication between each mobile station 11 and base station 12 by transmitting and receiving wirelessly while synchronizing predetermined frames via control channels and communication channels having different transmission speeds. Wireless communication means. Requests and grants of transmission rights are performed by random access via the control channel, and communication between the mobile stations 11 is performed via the communication channel.

  FIG. 4A shows a case where the base station 12 manages the control channel and the communication channel by setting the transmission rate of the control channel to 4800 [bps] and the transmission rate of the communication channel to 9600 s [bps]. Yes. FIG. 4B shows a case where the base station 12 manages the control channel and the communication channel with the transmission rate of the control channel set to 9600 [bps] and the transmission rate of the communication channel set to 4800 [bps]. Yes.

FIG. 2 shows a format of a communication frame in the communication system of FIG. As shown in the figure, the head of the frame is a synchronization word, the channel identification information field thereafter, and the control information field thereafter. The synchronization word is used to establish frame synchronization in communication between the base station 12 and the mobile station 11. The channel identification information field includes a radio channel identification area indicating whether the frame is a control channel frame or a communication channel frame, and a functional channel identification area indicating which functional channel is used. In the present embodiment, the radio channel identification area indicates whether the control channel is 4800 [bps] or 9600 [bps]. In the functional channel identification area, when it indicates a downlink common control channel, a new timing identification area is arranged to enable the setting as shown in the following table.

  That is, when the timing identification area is “0” and the control channel indicated by the radio channel identification area is 4800 [bps], the reception timing of the control channel frame in the mobile station 11 as shown in FIG. Indicates that it coincides with the timing of the control channel frames 41 and 43 in the base station 12, and if the control channel is 9600 [bps], the control channel frame in the mobile station 11 as shown in FIG. This indicates that the reception timing coincides with the timing of the frames 46 and 48 in the latter half of the control channel in the base station 12. Further, when the timing identification area is “0”, there is no setting for the control channel 4800 [bps], and if the control channel is 9600 [bps], the control channel in the mobile station 11 as shown in FIG. The reception timing of this frame indicates that it matches the timing of the first frame 51 or 53 of the control channel in the base station 12.

  In this configuration, the random access timing is as shown in FIGS. 4A to 4C, and the random access is performed according to the procedure described above with reference to FIG. That is, the random access in the case of the configuration of FIG. 1A is performed according to the timing of FIG. 4A, and the random access in the case of the configuration of FIG. 1B is the timing of FIG. 4B or FIG. Done according to

  At that time, when the base station 12 transmits a permission frame indicating which communication channel is permitted to communicate in response to a request frame requesting a transmission right from the mobile station 11, the control channel is 4800 [bps]. In this case, the timing identification area in the permission frame is transmitted as “0”. This permission frame is the frame 43 in FIG. When the control channel is 9600 [bps], when the 9600 [bps] request frame is arranged in the latter half of the 4800 [bps] frame section, the timing identification area in the permitted frame is transmitted as “0”. This permission frame is the frame 48 in FIG. When it is arranged in the first half, the timing identification area in the permission frame is set to “1” and transmitted. This permission frame is the frame 53 in FIG.

  When the communication mode is not different between the control channel and the communication channel, the timing identification area is set to “0” when the communication mode is 4800 [bps]. When it is 9600 [bps], it may be “0” or “1”. Not specifically specified.

  When the mobile station 11 receives a permission frame in the control channel, the mobile station 11 can recognize the transmission timing in the communication channel by examining the timing identification area. That is, when a permission frame is received on the 4800 [bps] control channel and the timing identification area is “0”, the timing in the control channel is maintained as shown in FIG. Transmission of the frame 44 in the communication channel is started 40 [ms] after the timing at which the frame is received.

  On the other hand, when a permission frame is received on the control channel of 9600 [bps], if the timing identification area is “0”, the timing in the control channel is maintained as shown in FIG. Transmission of the frame 49 in the communication channel starts 40 [ms] after the timing 48 is received. Further, when a permission frame is received on a control channel of 9600 [bps], if the timing identification area is “1”, as shown in FIG. 4C, 80 [ms] from the timing at which the permission frame 53 is received. After that, transmission of the frame 54 in the communication channel is started. Thereby, the mobile station 11 can always start transmission on the communication channel at an appropriate timing regardless of the reception timing of the permission frame.

  As described above, according to the present embodiment, when the mobile station 11 performs random access at 9600 [bps] on the control channel and performs communication at 4800 [bps] on the communication channel, the mobile station 11 is used for random access. Since the information indicating whether the frame is arranged in the first half or the second half in the frame section of the communication channel is included in the communication channel permission frame, the mobile station 11 always transmits the frame in the communication channel at an appropriate timing. It can be performed.

  Next, a mobile communication system according to another embodiment of the present invention will be described. As a system configuration diagram and a frame timing chart, FIGS. 1 and 4 can be applied as they are. That is, even in this case, the transmission speeds of the control channel and the communication channel are different, one transmission speed is 9600 “bps”, and the other transmission speed is 4800 [bps]. There are cases of FIGS. Therefore, also in this case, when the mobile station 11 performs random access at 9600 [bps] on the control channel and performs communication at 4800 [bps] on the communication channel, as shown in FIGS. 4B and 4C. However, there may be a timing shift at the time of transition to the communication channel. In order to avoid this, in this embodiment, instead of using the information by the timing identification area in Table 1 above, the superframe count information is used.

  That is, in this mobile communication system, a super frame is composed of a predetermined number of frames. When the mobile station 11 receives a super frame on the control channel, the mobile station 11 counts the order of frames from the top frame of each frame included in the super frame. Therefore, in this communication system, at the time of random access, depending on whether the mobile station 11 receives the odd-numbered frame or the even-numbered frame on the control channel when the order of the first frame is the first, 11 itself switches the transmission timing on the communication channel.

  That is, when the mobile station 11 receives even-numbered frames on the control channel and performs random access, the transmission timing on the communication channel is permitted to allow transmission on the communication channel as shown in FIG. The frame is transmitted on the communication channel 40 [ms] after the frame 48 is received. On the other hand, when the odd-numbered frame is received on the control channel and random access is performed, as shown in FIG. 4C, the transmission of the frame on the communication channel is performed 80 ms after receiving the permission frame 53. Do.

  However, in order to ensure that the transmission timing of frames in the communication channel is always appropriate, it is necessary to make the number of frames constituting the superframe an even number. This is because if the number is an odd number, the arrangement in the frame section of the communication channel for the same frame in each superframe is different for each superframe. Further, the base station 12 needs to transmit to the mobile station 11 after 40 ms after receiving the random access transmission frame of the mobile station 11. When the transmission rate on the control channel is an integer multiple of the transmission rate on the communication channel, the number of frames constituting the superframe may be an integer multiple of the integer.

  According to the present embodiment, when the mobile station 11 performs random access using the 9600 [bps] control channel and performs communication using the 4800 [bps] communication channel, the mobile station 11 itself is used for random access. Based on whether the frame is odd-numbered or even-numbered in the superframe, it is recognized whether the frame is arranged in the first half or the second half in the frame section of the communication channel, and the frame is transmitted on the communication channel. Therefore, it is possible to always transmit the frame on the communication channel at an appropriate timing without changing the frame format.

  Note that the present invention is not limited to the above-described embodiment, and can be implemented with appropriate modifications. For example, in the above description, an example in which an appropriate transition to the communication channel is described when the transmission speed of the communication channel is 4800 [bps] and the transmission speed of the control channel is twice that of 9600 [bps] has been described. The transmission rate and the transmission rate ratio are not limited to this example. For example, the present invention can be applied even when the transmission speed of the communication channel is 1200 [bps] and the transmission speed of the control channel is an integer multiple of 9600 [bps].

It is a block diagram which shows the mobile communication system which concerns on one Embodiment of this invention. It is a figure which shows the format of the communication frame in the communication system of FIG. It is a block diagram which shows the structural example of the conventional mobile communication system. It is a figure which shows the timing of the flame | frame at the time of the random access in the mobile communication system of FIG. FIG. 4 is a diagram illustrating frame timing at the time of random access in the mobile communication system of FIG. 3.

Explanation of symbols

  11, 31: Mobile station, 12, 32: Base station, 41-58: Frame.

Claims (7)

A plurality of mobile stations and a base station that relays communication between the mobile stations and manages transmission rights of the mobile stations, and the communication between each mobile station and the base station is a control channel at a first transmission rate. And transmitting and receiving wirelessly while synchronizing a predetermined frame via a communication channel at the second transmission rate, and requesting and granting the transmission right are performed by random access via the control channel, Communication between stations is a communication system performed through the communication channel,
Each mobile station transmits a frame requesting the transmission right via the control channel, and in response, the base station transmits a frame permitting the request to the mobile station, and the mobile station responds accordingly. A communication system comprising timing correction means for correcting a transmission timing of the frame so as to be an appropriate timing in the communication channel when a station starts transmission of the frame through the communication channel. . Radio communication means for transmitting and receiving a predetermined frame in synchronization with a plurality of mobile stations via a control channel based on a first transmission rate and a communication channel based on a second transmission rate. A base station apparatus that manages transmission rights of mobile stations and relays communication between the mobile stations via the communication channel,
A frame requesting the transmission right by random access is received from each mobile station via the control channel, and in response to this, a frame permitting the request is transmitted to the mobile station when possible. The base station apparatus includes information on timing at which the mobile station should start transmitting a frame in the communication channel based on the timing at which the request frame is received. Radio communication means for transmitting and receiving a predetermined frame in synchronization with a predetermined base station via a control channel based on a first transmission rate and a communication channel based on a second transmission rate, and via the control channel A mobile station apparatus that obtains a transmission right from a base station, and that communicates with other mobile stations via the communication channel by the base station,
A frame requesting the transmission right by random access is transmitted to the base station via the control channel, and a frame permitting the request transmitted by the base station in response thereto is received, and then the permission frame is received. The mobile station apparatus transmits a frame on the communication channel at a timing based on information on a transmission timing of the frame on the communication channel included in the communication channel.   4. The apparatus according to claim 2, wherein the first transmission rate is an integral multiple of the second transmission rate.   The apparatus according to claim 4, wherein the information on the transmission timing is information indicating a position in the frame section of the communication channel where the request frame is arranged. Radio communication means for transmitting and receiving a predetermined frame in synchronization with a predetermined base station via a control channel based on a first transmission rate and a communication channel based on a second transmission rate, and via the control channel A mobile station apparatus that obtains a transmission right from a base station, and that communicates with other mobile stations via the communication channel by the base station,
The first transmission rate is an integer multiple of the second transmission rate;
The frame of the control channel constitutes a super frame,
The number of frames constituting the superframe is an integer multiple of the integer;
The mobile station apparatus counts the order of each frame in the superframe each time it receives each frame constituting the superframe,
The mobile station device transmits a frame requesting the transmission right by random access to the base station via the control channel, and receives a frame permitting the request transmitted by the base station in response to the frame, Thereafter, the mobile station apparatus recognizes the frame transmission timing in the communication channel based on the count value of the superframe, and transmits the frame in the communication channel at the timing. A plurality of mobile stations and a base station that relays communication between the mobile stations and manages transmission rights of the mobile stations, and the communication between each mobile station and the base station is a control channel at a first transmission rate. And transmitting and receiving wirelessly while synchronizing a predetermined frame via a communication channel at the second transmission rate, and requesting and granting the transmission right are performed by random access via the control channel, Communication between stations is a communication method in a communication system performed via the communication channel,
Each mobile station transmits a frame requesting the transmission right via the control channel, and in response, the base station transmits a frame permitting the request to the mobile station, and the mobile station responds accordingly. A communication method, wherein when a station starts transmission of a frame through the communication channel, the transmission timing of the frame is corrected to be an appropriate timing in the communication channel.

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