JP2019161316A - Radio communication method, radio communication system and program - Google Patents

Abstract

To distribute many communication bands to a specific terminal, while providing mobile control itself continuously.SOLUTION: In a radio communication method in a radio communication system using a stationary station and a mobile station, a radio frame for use in the radio communication method includes at least a control system channel transmitting the information for use in mobile control, a non-control system channel transmitting the information other than that for use in the mobile control, a notice channel for notifying all mobile stations of the radio control information, and an access control channel for use in establishment of connection from the mobile station to the stationary station. The stationary station assigns at least one up and down channel pair of the control system channel to the mobile station, in the radio frame, changes over the up and down communication directions dynamically in the non-control system channel, and assigns the non-control system channel dynamically to the mobile station.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a wireless communication method for wireless communication used for mobile object control.

  In recent years, there has been a movement to utilize wireless communication to control a mobile object. For example, in the field of train control, ETCS (European Train Control System) Level 2 or later, CBTC (Communication Based Train Control), and the like are known. In the field of automatic driving of automobiles, V2X (Vehicle to Everything) is known. In communication used for mobile control, it is required to reduce packet error rate, latency, delay jitter, and the like.

  On the other hand, if a new communication infrastructure is established for mobile control only, and a separate communication module is prepared for each communication purpose, the cost will be high. It is desirable to have a communications infrastructure that can accommodate multi-purpose communications.

  In patent document 1, for the purpose of improving the arrival rate of communication data used for train control between a terrestrial radio base station and an onboard radio station, an onboard radio station and a terrestrial radio base station mounted on a train A train control system for controlling train operation by transmitting and receiving information including train control information, which is information for controlling train operation, via wireless communication, and train control information transmitted by a ground radio base station General transmission information, which is information other than train control information, is transmitted only once from a ground radio base station to one on-board radio station, and train control information is transmitted from a ground radio base station to one A train control system that repeatedly transmits to an on-board radio station a plurality of times, and the on-board radio station uses the train control information received first without causing data loss among train control information is disclosed. Been That.

International Publication No. 2016/129086

Abe et al., “Soft decision decoding in differential PSK modulation”, IEEJ Transactions C, Vol. 111, No. 11, pp 563-568, 1991

  In the method disclosed in Patent Document 1, radio communication resources are allocated to each train in a slot unit obtained by combining the half slot of train control information and the half slot of general information. Alternatively, there is a problem that flexible operation for temporarily increasing the transmission capacity of general information in the downlink direction is difficult. In other words, in Patent Document 1, the transmission capacity of general information can be increased by increasing the number of slots allocated to a certain train, and the transmission capacity of train control information is also increased.

  A typical example of the invention disclosed in the present application is as follows. That is, a radio communication method in a radio communication system using a fixed station and a mobile station, wherein a radio frame used in the radio communication method includes at least a control channel for transmitting information used for mobile control, and the mobile A non-control channel for transmitting information other than that used for control, a broadcast channel for notifying all the mobile stations of radio control information, and an access used for establishing a connection from the mobile station to the fixed station The fixed station allocates at least one uplink and downlink channel pair of the control channel to the mobile station in the radio frame, and the uplink and downlink communication directions in the non-control channel And the non-control channel is dynamically allocated to the mobile station.

  According to one aspect of the present invention, it is possible to allocate a large number of communication bands to specific terminals while continuously providing mobile control. Problems, configurations, and effects other than those described above will become apparent from the following description of embodiments.

It is a figure which shows the structural example of the system of the Example of this invention. It is a figure which shows the structural example of the radio | wireless transmission apparatus of a present Example. It is a figure which shows the structural example of the radio channel of a present Example. It is a figure which shows the structure inside the radio channel of a present Example. It is a figure which shows the example of the data modulation symbol arrangement | positioning in the radio channel of a present Example. It is a figure which shows the example of the DQPSK modulation of a present Example. It is a figure which shows the structural example of the radio | wireless transmission control calculating apparatus by the side of the fixed radio station of a present Example. It is a figure which shows the structural example of the configuration information memory of a present Example. It is a figure which shows the structural example of the mobile body management memory of a present Example. It is a flowchart of the process which the access management part of a present Example performs. It is a flowchart of the process which the scheduler of a present Example performs. It is a flowchart of the process which the MAC packet process part of a present Example performs. It is a figure which shows the structural example of the MAC data block of DCCH of a present Example. It is a figure which shows the structural example of the data block of SCH of a present Example. It is a figure which shows the structural example of the data block of BCH of a present Example. It is a figure which shows the Example of UCCH of a present Example. It is a figure which shows the structural example of ACCH of a present Example. It is a figure which shows the structural example of the radio signal processing arithmetic unit of a present Example. It is a figure which shows the structural example of the radio | wireless signal transmission / reception apparatus of a present Example. It is a figure which shows the structural example of the radio | wireless transmission control arithmetic unit by the side of the mobile body of a present Example. It is a figure which shows the operation | movement sequence at the time of a hand-over.

<Example 1>
FIG. 1 is a diagram illustrating a configuration example of a system according to an embodiment of this invention.

  The system according to this embodiment includes a control information transmission device 11, a non-control information transmission device 12, one or a plurality of fixed radio stations 13, and a backbone network 16 serving as a communication medium between them. Mobile stations provided in one or a plurality of mobile bodies 23 are connected to the fixed wireless station 13 by wireless communication. The backbone network 16 may be a wired network or a wireless network. Hereinafter, the mobile station that communicates with the fixed wireless station 13 will be referred to as the mobile body 23 and will be described as the mobile body 23 as a whole.

  The control information transmission device 11 is a device that bi-directionally transmits information related to the control of the moving body 23 to and from the moving body 23. For example, the control information transmission device 11 has a function of collecting position information of the moving body 23 from the moving body 23 and notifying the moving body 23 of a range in which the moving body 23 can move.

  The non-control information transmission device 12 is a device that bi-directionally transmits information other than control of the mobile body 23 to and from the mobile body 23. For example, the non-control information transmission device 12 has a function of collecting command information to be transmitted to a person operating the moving body 23, log information, video information, and the like from the moving body 23.

  The control information transmission apparatus 11 and the non-control information transmission apparatus 12 control upper layer communication, store IP packets and packets compliant with system-specific protocols in information transmission blocks in the wireless layer, and Two-way communication is performed between the control information transmission device 21 and the non-control information transmission device 22 on the 23 side.

  The wireless transmission device 14 and the antenna 15 are components of the fixed wireless station 13 and perform wireless communication between the wireless transmission device 24 and the antenna 25 of the moving body 23. Details of the wireless communication method will be described later.

  FIG. 2 is a diagram illustrating a configuration example of the wireless transmission devices 14 and 24 according to the present embodiment.

  In the present embodiment, the wireless transmission device 14 of the fixed wireless station 13 and the wireless transmission device 24 of the moving body 23 are partially different in operation, but may have the same configuration as hardware.

  The network interface device 101 is a device that performs wired or wireless communication according to a communication method defined between the control information transmission devices 11 and 21 and the non-control information transmission devices 12 and 22, and a physical layer used in the communication method. And a modem function for processing lower layers such as a data link layer and a MAC (Medium Access Control) layer. The network interface device 101 can use a chip or board having a general modem function.

  The packet buffer 105 is a queue for temporarily storing data that the network interface apparatus 101 transmits / receives to / from the control information transmission apparatuses 11 and 21 and the non-control information transmission apparatuses 12 and 22. The packet buffer 105 may be provided in a volatile memory built in the network interface device 101 or may be provided in a separate volatile memory.

  The wireless transmission control arithmetic device 102 includes devices such as a CPU, MPU, and DSP and a memory that stores a program to be executed. After the wireless transmission devices 14 and 24 are activated, the program is written in the memory to realize a necessary function. . This program is read from the program memory 110 and written through the common bus 109. The program memory 110 is composed of a nonvolatile memory.

  The boot processing device 111 controls writing of a program from the program memory 110 to the wireless transmission control arithmetic device 102. The boot processing device 111 includes a nonvolatile memory in which a boot control program is written and an MPU that executes a program on the memory. The MPU first loads the boot control program after the wireless transmission devices 14 and 24 are activated. Execute.

  The wireless control memory 107 is configured by a volatile memory, and the wireless transmission control arithmetic device 102 stores information related to wireless control with the moving body 23. For example, it is information relating to the assignment of a radio channel to the mobile unit 23, and details thereof will be described later.

  The wireless transmission buffer 106 is composed of a volatile memory, and is a buffer for exchanging information transmitted and received wirelessly between the wireless transmission control arithmetic device 102 and the wireless signal processing arithmetic device 103. The wireless transmission buffer 106 enables the wireless transmission control arithmetic device 102 and the wireless signal processing arithmetic device 103 to operate asynchronously. However, the wireless transmission control arithmetic device 102 and the wireless signal processing arithmetic device 103 (for example, realized by a DSP). When performing a synchronous operation, the wireless transmission buffer 106 can be omitted.

  The wireless signal processing arithmetic device 103 has a function of converting an information bit sequence and a baseband digital signal, and is realized by a DSP, FPGA, or the like. Details will be described later. The function of the wireless signal processing arithmetic device 103 may be realized by a program. The program is read from the program memory 110 when the wireless transmission devices 14 and 24 are activated by the same procedure as the wireless transmission control arithmetic device 102.

  The signal processing memory 108 stores buffers and tables that are referred to by the wireless signal processing arithmetic device 103. Even in a volatile memory built in the wireless signal processing arithmetic device 103 (DSP or FPGA), a separate volatile memory is stored. Memory may be used.

  The wireless signal transmission / reception device 104 has a conversion function between a baseband digital signal and a high-frequency analog signal, and includes an A / D (analog digital) converter, a D / A (digital analog) converter, a filter, a mixer, an amplifier, and the like. A wireless communication module. In the present embodiment, in order to perform TDD (Time Division Duplex) communication, a switch for switching between transmission and reception is provided on the antenna side. The high frequency analog signal is transmitted / received via the antennas 15 and 25.

  FIG. 3 is a diagram illustrating a configuration example of a radio channel according to the present embodiment. In the following description, radio communication transmitted from the mobile unit 23 and received by the fixed radio station 13 is defined as uplink communication, and radio communication transmitted from the fixed radio station 13 and received by the mobile unit 23 is defined as downlink communication.

  Frames 201 having the same time length are continuously arranged in time. In the frame 201, a broadcast channel 202, a downlink mobile control information transmission channel 203, an uplink mobile control information transmission channel 204, an access control channel 205, and a non-control information shared transmission channel 206 are arranged in a time division manner. The The channel time division arrangement is the same for all frames 201. The broadcast channel 202 is a channel for transmitting common radio control information from the fixed radio station 13 to all the mobile units 23 within the radio coverage of the fixed radio station 13. The downlink mobile unit control information transmission channel 203 is a channel for transmitting information related to the control of the mobile unit 23 from the fixed radio station 13 to the mobile unit 23. The uplink mobile unit control information transmission channel 204 is a channel for transmitting information related to the control of the mobile unit 23 from the mobile unit 23 to the fixed radio station 13. The access control channel 205 is a channel for the mobile unit 23 that has not established a connection with the fixed wireless station 13 to transmit a connection request to the fixed wireless station 13. The non-control information sharing transmission channel 206 is a channel for transmitting information other than the mobile control between the fixed wireless station 13 and the mobile unit 23, and is shared between the plurality of mobile units 23, Downlink communication can be switched.

  Each channel described above is further time-divided into one or a plurality of channels. Also, frequency hopping may be performed so that each time division channel is transmitted at a different frequency. Frequency hopping is not essential for the implementation of the present invention. However, in communication that requires reliability such as control of the mobile unit 23, a sufficient frequency bandwidth can be secured in the system, and frequency hopping is applied. It is desirable to obtain a frequency diversity effect. BCH 207 is a time division channel of broadcast channel 202, DCCH 208 is a time division channel of downlink mobile control information transmission channel 203, UCCH 209 is a time division channel of uplink mobile control information transmission channel 204, and ACCH 210 is an access control channel 205. A division channel, SCH 211 is a time division channel of the non-control information shared transmission channel 206. In the present embodiment, four BCHs 207, four DCCHs 208, four UCCHs 209, four ACCHs 210, and two SCHs 211 are described in one frame, but these are only examples, and each radio channel is 1 The present invention can be implemented if there is at least one in the frame.

  FIG. 4 is a diagram showing a configuration inside the radio channel of the present embodiment.

  Each of the time division channels such as BCH 207, DCCH 208, UCCH 209, ACCH 210, and SCH 211 shown in FIG. 3 is configured as shown in FIG. A preamble 221 known on the receiving side is arranged at the head of the time division channel. On the receiving side, the reception timing and frequency shift of the time division channel can be detected by the preamble 221.

  Behind the preamble 221 is data 222 of each channel. Data 222 is generated by adding an error detection code or error correction coding to an information bit sequence and performing radio signal processing such as modulation. Details of the radio signal processing will be described later. In this embodiment, differential QPSK (DQPSK) is adopted as the primary modulation scheme and OFDM is adopted as the secondary modulation scheme. However, the present invention can also be realized by other modulation schemes as long as each channel is time-divisionally arranged. is there.

  A guard section 223 between wireless channels, which is a non-transmission section, is arranged at the end. Due to the guard section 223, a shift in reception timing caused by a distance between the mobile unit 23 and the fixed radio station 13 in uplink transmission, switching between uplink communication and downlink communication in a frame, and a timing shift between the fixed radio stations 13 Can be absorbed.

  As shown in FIG. 4, BCH 207, DCCH 208, UCCH 209, and ACCH 210 have the same configuration. By adopting the same configuration for these time division channels, the configuration of the receiver can be simplified. Since the SCH 211 is a channel used for various purposes, a longer time is allocated to the data 222 so that a larger payload can be loaded compared to the BCH 207 or the like. In the case of the data arrangement shown in (2-1) in the figure, the size of the encoded block is larger than that of the BCH 207 or the like. In a cellular system or the like, various coding block sizes are defined, and a method of efficiently utilizing the transmission capability of a radio propagation path is used together with an adaptive modulation technique. This concept has an advantage that the transmission capability of the wireless propagation path can be efficiently utilized, but has a demerit that the transmitter / receiver becomes complicated to cope with various block sizes and modulation schemes. Real-time feedback control for adaptive modulation is also complicated.

  On the other hand, as shown in (2-2), the data unit 222-3 may be configured by arranging a plurality of blocks having the same block size as the BCH 207 or the like. In this case, although it is inferior to the above-described method (2-1) in terms of efficient utilization of the wireless transmission capability, there is an advantage that the receiver can be simplified. In particular, since the system used for controlling the moving body 23 requires reliability, the method (2-2) may be preferable to the method (2-1) that requires man-hours for development and testing. In this embodiment, the channel configuration other than the SCH 211 employs the method (1), and the channel configuration of the SCH 211 employs the method (2-2).

  FIG. 5 is a diagram illustrating an example of the data modulation symbol arrangement in the radio channel according to the present embodiment.

  From the viewpoint of simplifying the configuration of the receiver, the number of OFDM symbols is the same for all radio channels such as BCH 207 and SCH 211. However, when the SCH 211 is configured as shown in FIG. 4 (2-1), only the SCH 211 has a larger number of OFDM symbols than the BCH 207 or the like. In the present embodiment, the SCH 211 has the same number of OFDM symbols as other radio channels. In this embodiment, the number of subcarriers is 16 and the number of OFDM symbols is 9. However, this number should be determined in consideration of the number of radio channels to be secured, the system bandwidth, the transmission rate required for the application, and the like. The present invention can be implemented as long as at least the modulation symbols excluding the reference are secured in each radio channel by the amount of information desired to be transmitted through the broadcast channel or the like.

  On the grid of OFDM symbols and subcarriers, a phase reference symbol 231 for performing differential QPSK modulation, a guard subcarrier and DC subcarrier 232, a data symbol 233 after differential QPSK modulation, and from inside and outside the system A null symbol 234 for observing interference is arranged. In the data symbol 233 and the null symbol 234, no symbol having amplitude is arranged.

  Various arrangements of the data symbol 233 and the null symbol 234 are conceivable. However, the data symbol 233 and the null symbol 234 can be roughly classified into (1) a method of arranging the null symbol 234 on the same subcarrier with different OFDM symbols, There is a method of arranging in different subcarriers. In the method (1), DQPSK modulation is performed based on the phase of the previous OFDM symbol of the same subcarrier, so that DQPSK modulation itself can be simply realized, but narrowband interference generated between the null symbols 234. Is difficult to observe. In other words, since the receiving side cannot recognize the interference generated between the null symbols 234, the estimation accuracy of the likelihood for each bit to be referred to at the time of demodulation and decoding is lowered, and the error rate characteristic of the channel is deteriorated. Become. In an environment where such narrow-band interference does not occur, the arrangement of the null symbols 234 as shown in (1) does not cause a problem. On the other hand, in an environment where narrow-band interference can occur, it is better to place null symbols 234 on different subcarriers as shown in (2).

  In this embodiment, one null symbol 234 is arranged for every three subcarriers, but this is optimized according to the transmission rate required by the application and the bandwidth and duration of the interference to be observed. Is the value to be done. The more null symbols 234 are arranged, the narrower the band and the shorter the duration of interference can be captured. Even in the case of interference with a narrow band and a short duration, if the frequency of occurrence is low, the fact that it can be overcome by an error correction code is also taken into consideration during optimization. That is, the arrangement density of the null symbols 234 is an optimization parameter corresponding to the assumed application and assumed interference, and if the number of data symbols can secure the amount of information that needs to be transmitted on a radio channel such as the BCH 207, the null symbols 234 are arranged. Even if there are many, it can be implemented with the present invention. However, when the null symbol 234 is arranged as shown in (2), a device that is not considered in (1) is required when performing DQPSK modulation. This will be described with reference to FIG.

  FIG. 6 is a diagram illustrating an example of DQPSK modulation according to the present embodiment.

  FIG. 6 shows a grid of physical subcarriers and OFDM symbols. As shown, logical subcarriers exemplified as 241 in a range excluding guard subcarriers, DC subcarriers 232, and null symbols 234. Define The first OFDM symbol of each logical subcarrier has a DQPSK modulation phase reference symbol 231, and thereafter, the preceding OFDM symbol and a DQPSK modulation symbol based on the phase of the same logical subcarrier are arranged. The phase reference symbol and the first DQPSK modulation symbol in the same logical subcarrier are selected to be the same physical subcarrier. This is because, when differential modulation is performed, it is desirable that the channel response between the modulation target symbol and the symbol serving as the phase reference of the symbol has a high correlation. It can be expected that differential modulation is performed in combination.

  FIG. 7 is a diagram illustrating a configuration example of the wireless transmission control arithmetic device 102 on the fixed wireless station 13 side of the present embodiment.

  The packet buffer 105 provided between the network interface device 101 includes a control information buffer 301 and a non-control information buffer 302. The control information buffer 301 is a buffer for temporarily storing packets transmitted to and from the control information transmission apparatus 11, and the non-control information buffer 302 is a packet transmitted to and from the non-control information transmission apparatus 12. Is a buffer that temporarily stores. In the case of uplink communication, when a transmission packet is stored, it is transferred by the network interface device 101 to the control information transmission device 11 and the non-control information transmission device 12. In the case of downlink communication, the packet stays in the packet buffer 105 until the wireless communication channel is assigned by the scheduler 305. Packets stored in the control information buffer 301 are transmitted through the wireless channels DCCH 208 and UCCH 209, and packets stored in the non-control information buffer 302 are transmitted through the SCH 211.

  The radio control memory 107 includes a configuration information memory 303 (see FIG. 8) and a mobile management memory 304 (see FIG. 9). The configuration information memory 303 is a memory that stores setting parameters unique to the fixed wireless station 13 and necessary parameters for performing communication with the mobile unit 23 connected to the fixed wireless station 13. is there. For example, parameters relating to frequency hopping and null symbol arrangement method rules. The contents of the configuration information memory 303 are notified to the mobile unit 23 through the BCH 207. The mobile unit management memory 304 is a memory that manages the identifier of the mobile unit 23 connected to the fixed radio station 13, the radio channel assigned to each mobile unit 23, and the retransmission status of non-control information. When the mobile unit 23 establishes a connection with the fixed radio station 13, a storage area for the mobile unit is secured in the mobile unit management memory 304. When the mobile object 23 implicitly or explicitly disconnects from the fixed wireless station 13, the storage area of the mobile object 23 is deleted from the mobile object management memory 304.

  The scheduler 305 assigns the mobile unit 23 that performs packet transmission in uplink and downlink communication on the radio channels DCCH 208, UCCH 209, and SCH 211 in the frame. Further, the scheduler 305 reads configuration information transmitted by the BCH 207, manages the frame number, notifies the MAC packet processing unit 306 of the frame number, and designates a usable mobile identifier for each of the ACCHs 210. The scheduler 305 notifies the MAC packet processing unit 306 of the above-described assignment result in order to notify the mobile unit 23 via the BCH 207. In this embodiment, DCCH 208, UCCH 209, BCH 207, and ACCH 210 do not assume retransmission in the radio layer, but SCH 211 performs ARQ retransmission. The retransmission of the SCH 211 is managed in the mobile management memory 304. The scheduler 305 refers to the mobile management memory 304, and when there is an SCH 211 that requires retransmission, the allocation priority of the SCH 211 that requires the retransmission. Raise. However, as configuration information for each fixed wireless station 13, an upper limit may be set for the number of retransmissions.

  The MAC packet processing unit 306 has processing on the transmission side and processing on the reception side.

  As processing on the transmission side of the MAC packet processing unit 306, a sequence number that is a packet serial number is generated for each mobile radio channel. In the retransmission packet of SCH 211, the sequence number of the packet to be retransmitted is given. The generated sequence number is added to the head of data such as the control information buffer 301 as header information, and is written in the control channel buffer 308 or the like. The BCH 207 acquires configuration information, a frame number, and radio channel allocation information from the configuration information memory 303 and the scheduler 305, and generates a data block. A MAC header including a sequence number is added to the head of the data block. When requesting retransmission of the uplink SCH 211, information indicating a packet to be retransmitted is added to the MAC header of the DCCH 208. Which uplink SCH 211 is subject to retransmission refers to the reception result of the uplink SCH 211 recorded in the non-control channel buffer 309. This operation is related to processing on the receiving side described later.

  As processing on the reception side of the MAC packet processing unit 306, received data is acquired from each channel buffer (control channel buffer 308, non-control channel buffer 309, broadcast channel buffer 310), and the MAC header is analyzed. If the sequence number overlaps with the data received in the past, the received packet is discarded if the received data is other than SCH 211 or is not subject to retransmission in SCH 211, that is, if the sequence number has already been successfully received. If the SCH 211 is to be retransmitted, it is combined with the results received in the past, and after all the data has been prepared, the data is written into the non-control information buffer 302. If some of the data is not complete, the received data is accumulated in the non-control channel buffer 309 and the range that requires retransmission (the retransmission target of the uplink SCH 211) is stored in the mobile management memory 304. Even when there is a missing sequence number, the range that needs to be retransmitted is stored in the mobile management memory 304. When the SCH 211 is to be retransmitted and the number of retransmissions reaches the upper limit, the data stored in the non-control channel buffer 309 is discarded. When the received data is ACCH 210 data, the received packet is transferred to the access management unit 307 as it is. The MAC header of the UCCH 209 may store a downlink SCH 211 retransmission request, and when the MAC packet processing unit 306 confirms the retransmission request, the information in the mobile management memory 304 is updated.

  The access management unit 307 manages the number of moving bodies 23 connected to the fixed wireless station 13. When reference is made to the mobile management memory 304 using the input of the ACCH 210 as a trigger, and the mobile 23 that is not recorded in the mobile management memory 304 and does not exceed the upper limit of the number of mobiles 23 that can be connected to the fixed radio station 13 The moving body 23 is added to the moving body management memory 304. However, if the access is from other than the mobile unit 23 permitted by the scheduler 305, the ACCH 210 is discarded. Although related to the handover described later, the mobile unit 23 that moves from the fixed radio station 13 to another fixed radio station 13 is deleted from the mobile unit management memory 304. The implicit deletion from the mobile management memory 304 when communication on the mobile side is interrupted is determined by the MAC packet processing unit 306 based on a comparison result between the number of consecutive reception failures of the UCCH 209 and a predetermined threshold.

  FIG. 8 is a diagram illustrating a configuration example of the configuration information memory 303 according to the present embodiment.

  The configuration information memory 303 stores, as a configuration value, contents that should be notified in common to all the mobile units 23 connected to or about to connect to the fixed wireless station 13. The configuration value stored in the configuration information memory 303 is transmitted to the mobile unit 23 via the broadcast channel (BCH) 207 of each frame. The contents stored in the configuration information memory 303 include an identifier 3031 of the fixed radio station 13, a rule of null symbol arrangement method (subcarrier offset value of null symbol arrangement) 3032, a rule of frequency hopping (frequency hopping interval 3033, frequency Frequency channel offset value 3034) serving as a hopping base point.

  The subcarrier offset value of the null symbol arrangement is, for example, a null symbol that overflows upward by shifting the null symbol upward by one subcarrier as a whole, with the null symbol arrangement shown in FIG. Is a configuration value for shifting the arrangement of null symbols between the fixed radio stations 13 such that the subcarrier offset value is 1 or the like. When null symbols are arranged in this manner, mutual interference between fixed radio stations 13 having the same frequency hopping pattern can be measured using null symbols.

  Frequency hopping will be described using mathematical expressions.

  When L frequency channels can be arranged in the entire wireless system, the frequency channel F applied to a certain wireless channel can be calculated by the following equation.

  Here, frame is a frame number generated by the scheduler 305, and offset and step are a frequency hopping offset and a frequency hopping step, which are configuration values, respectively. Also, i is the serial number of the intra-frame radio channel. For example, in the example shown in FIG. 3, 0 to 3 for BCH # 0 to # 3, 4 to 7 for DCCH # 0 to # 3, UCCH # 0 to ## 3 is assigned 8 to 11, ACCH # 0 to # 3 is assigned 12 to 15, and SCH # 0 to # 2 are assigned 16 to 18. mod5 indicates a modulo operation, and is an operation for obtaining a remainder obtained by dividing an argument by 5.

  FIG. 9 is a diagram illustrating a configuration example of the mobile management memory 304 of the present embodiment.

  A mobile body management table 304A shown in FIG. 9A is a table for managing each mobile body connected to the fixed wireless station 13.

  The mobile unit identifier 3041 stores a value transmitted by the mobile unit 23 on the access control channel (ACCH) 210 as it is. The control channel allocation period 3042 and the control channel allocation offset 3043 are set so that when the mobile unit 23 establishes a connection with the access control channel 210, other mobile units are considered in consideration of the control channel allocation state to the already connected mobile unit 23. This value is determined by the access management unit 307 so as not to overlap with the field 23. In the example shown in FIG. 3, four pairs of a downlink control channel (DCCH) 208 and an uplink control channel (UCCH) 209 are provided in the frame, and since the channel allocation period is 8 in this system, two frames are provided. Once, a control channel is assigned to the mobile body 23. The frame number is frame, the serial number of the control channel pair in the frame is n (corresponding to DCCH # n and UCCH # n), the number of control channel pairs in the frame is M, the channel allocation period is K, and the mobile unit is allocated. Assuming that the control channel allocation offset is offset, the control channel pair that can be used by the mobile unit 23 satisfies the following formula.

  The downlink non-control information untransmitted data amount 3044 is an untransmitted data amount related to the moving body 23 stored in the non-control information buffer 302. The amount of downlink non-control information untransmitted data increases due to the occurrence of downlink non-control information, and when no retransmission request is generated after transmission to the mobile unit 23, that is, when the transmission to the mobile unit 23 is successful, the fixed radio station Decrease when 13 is determined.

  The uplink non-control information untransmitted data amount 3045 is an untransmitted non-control information data amount held by the mobile body 23. Each time the amount of non-control information data transmitted from the mobile unit 23 is received in the UCCH 209, it is updated to the latest value, and is decreased by the amount of non-control information data successfully transmitted from the mobile unit 23 via the SCH 211.

  The downlink non-control information transmitted last sequence number 3046 is the total number of data blocks of non-control information transmitted to the mobile body 23. Even when a retransmission request is received for a transmitted data block, this number does not change. In the case of the configuration of (2-2) in FIG. 4, a block divided by a broken line is defined as one data block. That is, when non-control information is transmitted with the configuration of (2-2) in FIG.

  In the downlink non-control information retransmission request sequence number list 3047, when a sequence number that needs to be retransmitted is notified from the mobile unit 23 through the UCCH 209, the sequence number is added. When the non-control information of the sequence number to be retransmitted is transmitted on the SCH 211 and it is confirmed that no retransmission request is generated from the mobile unit 23, the sequence number is deleted from the downlink non-control information retransmission request sequence number list 3047. .

  The uplink non-control information received final sequence number 3048 is the value of the final sequence number included in the MAC header transmitted from the mobile unit 23 via the SCH 211. That is, the final sequence number 3048 having received the uplink non-control information is updated by copying the value of the final sequence number managed by the mobile unit 23 itself.

  In the uplink non-control information retransmission request sequence number list 3049, the sequence numbers corresponding to the data blocks that have failed to be received among the data blocks transmitted from the mobile unit 23 via the SCH 211 are added. When reception is successful due to retransmission of a data block that has failed to be received, the sequence number is deleted from the uplink non-control information retransmission request sequence number list 3049.

  The uplink control information continuous reception failure count 3050 records the number of continuous failures in the reception of the UCCH 209 of the mobile unit 23. As described in the description of FIG. 7, when communication on the mobile unit 23 side is interrupted by the determination using the threshold value of this number, the mobile unit 23 is implicitly deleted from the mobile unit management memory 304.

  An ACCH management table 304B shown in FIG. 9B is a table for managing the access control channel (ACCH) 210. The scheduler 305 sets a table value and is referenced by the access management unit 307. In the ACCH management table 304B, an identifier of the mobile unit 23 that can use each ACCH 210 in the frame is recorded. A part of all mobile unit identifier values is defined as a reserved value for all mobile unit accessible and all mobile unit inaccessible. For example, 0x0000 may be inaccessible to all mobile units, and 0xFFFF may be accessible to all mobile units. The value indicating that all mobile units cannot be accessed is used when the number of mobile units 23 connected to the fixed wireless station 13 has reached the limit. The value indicating that all mobile units can be accessed is used in a normal state except when a resource is reserved for a specific mobile unit 23 by handover.

  FIG. 10 is a flowchart of processing executed by the access management unit 307 of this embodiment.

  When started, the access management unit 307 waits for an ACCH 210 input from the MAC packet processing unit 306 in step 1001. When the input of the ACCH 210 is confirmed, the ACCH management table 304B shown in FIG. 9B is referred to in step 1002, and the number of the ACCH 210 is compared with the mobile object identifier included in the ACCH 210. To determine if access is permitted. If access is permitted, it is confirmed in step 1003 whether or not the mobile object management table 304A shown in FIG.

  If the mobile management table 304A is already secured, the secured mobile management table 304A is reused. At the time of reconnection operation after temporary communication disconnection, the mobile management table 304A is secured. If the mobile unit management table 304A is not secured, an access control channel (ACCH) 210 that is not yet used by the mobile unit 23 connected to the fixed wireless station 13 is allocated in step 1004, and the mobile unit 23 A new storage area is created. At the time of new connection including handover, the mobile unit management table 304A is not secured, and a new mobile unit management table 304A is secured.

  FIG. 11 is a flowchart of processing executed by the scheduler 305 of this embodiment.

  When the scheduler 305 is activated, the scheduler 305 starts radio channel allocation processing at every frame period (for example, 100 ms) in step 1011 based on the time managed by the hardware of the radio transmission control arithmetic device 102. When the allocation process starts, first, 1 is added to the frame number in step 1012.

  Next, in step 1013, the mobile unit management table 304A and the frame number shown in FIG. 9A are referred to, and the identifiers of the mobile units 23 to which the DCCH 208 and the UCCH 209 are allocated are the number of channel pairs in the frame in the order of the channel pair numbers. assign. Channel pair number N corresponds to a pair of DCCH # N and UCCH # N. When the number of mobile bodies 23 connected to the fixed wireless station 13 is small and there is no mobile object 23 to be assigned, for example, 0x0000 may be assigned as the mobile body identifier. This number is preferably matched with the reserved mobile identifier that cannot be accessed by all mobile units shown in the description of the ACCH management table 304B shown in FIG. 9B, and access from the mobile unit 23 to the channel is prohibited.

  Next, in step 1014, the SCH 211 is allocated. Various methods are known for dynamic scheduling, but the simplest round robin is considered here. As an example, assume a token that first makes a round of mobile identifiers in downlink communication, then makes a round of mobile identifiers in uplink communication, and repeats the operation of returning to downlink communication again. With regard to the communication direction and the mobile identifier that the token has come to, the presence / absence of untransmitted data and the presence / absence of retransmission data are determined with reference to the mobile management table 304A shown in FIG. When there is data to be transmitted (untransmitted data, retransmission data), search is performed in order from SCH # 0, and if there is an empty channel, SCH 211 in the communication direction is assigned to mobile unit 23. When the data presence / absence determination and the SCH 211 assignment are completed, a token is transferred to the next mobile unit 23. The above processing is repeated until all the SCH 211 is allocated or there is no non-control information to be transmitted on the SCH 211. If there is an unassigned SCH 211 after one round of the token, a mobile identifier of 0x0000 is assigned to the unassigned SCH 211. The token position after the end of frame scheduling is the initial value for the frame scheduling operation in the next frame. The token position at startup can be anywhere.

  Next, in step 1015, the ACCH 210 is allocated. First, when the number of mobile units 23 connected to the fixed radio station 13 has reached the upper limit, that is, when there is no capacity to allocate a control channel, mobile unit identifiers indicating that all mobile units 23 are inaccessible. Assign 0x0000 to all ACCHs 210 and finish the assignment. In other cases, a mobile unit identifier 0xFFFF indicating that all mobile units 23 can be accessed is assigned to all ACCHs 210, and connection schedules due to handovers from mobile units 23 connected to other fixed radio stations 13 are scheduled. Check for presence. If there is a connection schedule, the mobile unit identifier is assigned to one of the ACCHs 210. The mobile unit identifier may be overwritten on the ACCH 210 initialized with 0xFFFF in ascending order of the ACCH 210 number.

  Next, in step 1016, DCCH 208, UCCH 209, SCH 211, and ACCH 210 assignment results, that is, a list in which radio channels and mobile unit identifiers are associated one-to-one are output to MAC packet processing section 306.

  FIG. 12 is a flowchart of processing executed by the MAC packet processing unit 306 of this embodiment.

  The MAC packet processing unit 306 generates a downlink packet and outputs it to the wireless signal processing arithmetic device 103, and a function of analyzing the upstream packet received by the wireless signal processing arithmetic device 103 and updating the contents of various buffers and memories. There is.

  The downlink packet generation process starts when a notification of completion of radio channel assignment by the scheduler 305 is received in step 1021 in the form of interprocess communication, interthread communication, or function call. Subsequent processing does not affect the feasibility of the present invention even if the order of execution is changed.

  First, in step 1022, all DCCH 208 data blocks are generated from DCCH # 0 to DCCH # N-1 in the order of channel numbers.

  FIG. 13 is a diagram illustrating a configuration example of the MAC data block of the DCCH 208 according to the present embodiment.

  The MAC data block of the DCCH 208 includes a MAC header 2001 and a data body 2002. The data body 2002 refers to the allocation target mobile unit identifier received from the scheduler 305 with respect to the DCCH #n, and reads a bit string from the control information buffer 301 related to the mobile unit identifier by the amount of data that can be transmitted on the physical layer of the DCCH 208. If the length of the read bit string is less than the amount of data that can be transmitted by the physical layer of the DCCH 208, padding processing is performed on the read data, and additional bits are added after that. For this reason, the number of valid data block bytes excluding padding is stored in the MAC header 2001.

  At the time of initial transmission to the mobile unit 23, the downlink control information sequence number is set to 0, and is incremented by 1 each time a different data block is transmitted. When the same data block is transmitted multiple times, the sequence number is not updated. The uplink non-control information final sequence number indicates the final sequence number transmitted from the mobile unit 23 through the SCH 211, and refers to the downlink non-control information transmitted final sequence number 3046 in the mobile unit management table 304A illustrated in FIG. To do. The uplink non-control information retransmission request bitmap is a bit map indicating a retransmission request for a data block with s sequence numbers going back with reference to the final non-control information sequence number. Here, the most significant bit of the bitmap indicates the upstream non-control information final sequence number itself, that is, s = 0, the second upper bit corresponds to the sequence number of s = 1, and the bit value is set to 1 A re-transmission of the number is requested. This retransmission request sequence number is generated based on uplink non-control information received final sequence number 3048 and uplink non-control information retransmission request sequence number list 3049 in the mobile management table 304A shown in FIG. 9A.

  In addition, when the mobile identifier to be allocated in a certain DCCH # n is 0x0000, instead of generating a MAC data block and inputting it to the radio signal processing arithmetic unit 103, a Disabler for not generating a radio signal in the DCCH 208 is used. It may be input to the wireless signal processing arithmetic device 103.

  When the generation of the DCCH 208 data block is completed, the MAC packet processing unit 306 generates the SCH 211 data block in step 1023. If SCH #n has no downlink communication, this step is skipped for SCH #n. When SCH # n is downlink communication, the data block of SCH211 shown in FIG. 14 is generated.

  FIG. 14 is a diagram illustrating a configuration example of a data block of the SCH 211 according to the present embodiment.

  The data block of the SCH 211 includes a MAC header 2003 and a data body 2005 for the SCH 211. The data body reads the bit string from the non-control information buffer 302 by the amount of data that can be transmitted by the physical layer SCH 211, but may not match the upper layer delimiter such as an IP packet. For this reason, the MAC header for the SCH 211 needs information indicating how many IP packets are included in the data block of the SCH 211. Specifically, the number of segments that are the number of IP packets, the byte position that is the end of the segment immediately after the MAC header is 0, and information indicating which part of the IP packet is included are the MAC header for SCH211. Include in For example, the information indicating which part of the IP packet is included indicates whether each segment includes only the head of the IP packet (bit flag 0b10), only the end (bit flag 0b01), the start and end (Bit flag 0b11) or whether it does not include the beginning or end (bit flag 0b00).

  When such segmentation is performed, the length of the MAC header becomes variable because the number of segments becomes indefinite. Therefore, the length information of the MAC header itself is also included in the MAC header.

  Similar to the DCCH 208, the effective data block size is a size that does not include padding in the MAC header and the data body. Padding is generated to fill the difference when the amount of data existing in the non-control information buffer 302 is smaller than the amount of data that can be transmitted by the physical layer SCH 211.

  The downlink non-control information final sequence number is the last sequence number among the serial numbers of one data block transmitted in (2-1) in FIG. 4 or a plurality of data blocks transmitted in (2-2). Set. The downlink non-control information final sequence number is assigned 0 for the data block transmitted for the first time to the mobile unit 23, and thereafter increases by 1 each time a data block is generated.

  The downlink non-control information sequence number bitmap is not necessary when a single data block as shown in (2-1) in FIG. 4 is transmitted via the SCH 211, but a plurality of data blocks as shown in (2-2) are not included in the SCH 211. In the case of sending the data block, it indicates how many data blocks of the sequence number before the downlink non-control information last sequence number are transmitted. The most significant bit corresponds to the last sequence number, the second upper bit corresponds to the sequence number one before the last sequence number, and so on.

  In this method, the sequence numbers transmitted in a plurality of data blocks can be known, but it is not known what number each sequence number is located in the data block. For this reason, a data block having a young sequence number is arranged in a data block close to the MAC header, and the data block is arranged so that the sequence number increases as the distance from the MAC header increases.

  When determining a data block to be transmitted, priority is given to retransmission of a data block having a sequence number having a number in the downlink non-control information retransmission request sequence number list 3047 with reference to the mobile management table 304A shown in FIG. To do. If there is no data block to be retransmitted, new data blocks corresponding to the number of data blocks in SCH 211 are generated from the sequence number next to the last sequence number 3046 transmitted in the downlink non-control information in the mobile management table 304A. At this time, the data block for retransmission and the data block for non-retransmission may be mixed. For example, in the case of (2-2) in FIG. 4, there are three data blocks in the SCH 211, among which the retransmission data block is arranged in the first data block and the non-re-transmission data block is arranged in the remaining two. The receiving side can identify whether each data block is to be retransmitted by the downlink non-control information final sequence number and the downlink non-control information sequence number bitmap in the MAC header.

  When the SCH 211 data block generation ends, the MAC packet processing unit 306 next generates a BCH 207 data block in step 1024. One data block of the BCH 207 is generated, and the generated data block is transmitted on all the BCHs 207 in the frame.

  FIG. 15 is a diagram illustrating a configuration example of a data block of the BCH 207 according to the present embodiment.

  The data block of the BCH 207 includes a MAC header 2006 for the BCH 207 and a data body 2007. The MAC header includes a MAC header excluding padding, the number of valid data block bytes indicating the length of a valid data block, and a downlink broadcast information sequence number to which 1 is added every time the BCH 207 is updated, as in the SCH 211 and the like. . Since all the BCHs 207 in the frame transmit the same data block, the downlink broadcast information sequence number is incremented by 1 every time the frame is updated.

  The data body of the BCH 207 includes a fixed radio station identifier, a null symbol offset value, a frequency hopping interval, a frequency hopping offset, a frame number that is an output of the scheduler 305, and each radio channel in the frame stored in the configuration information memory 303. Contains a list of assigned mobile identifiers.

  The DCCH / UCCH # n mobile unit identifier is an identifier of the mobile unit 23 to which a channel pair of DCCH # n and UCCH # n in the frame is assigned. The SCH # m mobile unit identifier is a combination of the identifier of the mobile unit 23 to which the SCH # m in the frame is assigned and the communication direction (UL; uplink, Uplink, or DL; downlink, Downlink). The ACCH # k mobile unit identifier is an identifier of the mobile unit 23 that can be accessed using the ACCH # k.

  The DCCH 208 data block generated as described above is written into the control channel buffer 308, the SCH 211 data block is written into the non-control channel buffer 309, and the BCH 207 data block is written into the broadcast channel buffer 310. The data block overwritten in the channel buffer is read by the wireless signal processing arithmetic unit 103 at its own timing to generate a wireless channel.

  Next, the processing of steps 1025 to 1028 in FIG. 12 will be described. In steps 1025 to 1028, the processing is started when the decoding processing of all the uplink radio channels is completed on the radio signal processing arithmetic device 103 side. Completion of the decoding process is a flag written by the wireless signal processing arithmetic device 103 to the register for notification provided in the buffer between the transmission of the interrupt signal from the wireless signal processing arithmetic device 103 to the wireless transmission control arithmetic device 102. When (for example, 1) is detected by the radio transmission control arithmetic unit 102 (step 1025), the radio transmission control arithmetic unit 102 writes 0 in this register, and the control channel buffer 308, the non-control channel buffer 309, the broadcast channel buffer 310, and The decoding result of each uplink radio channel is acquired from the access control channel buffer 311. The obtained decoding result includes a MAC header, a valid data block, padding, and an indicator indicating success or failure of decoding.

  Upon receiving the uplink radio channel decoding process completion notification from the radio signal processing arithmetic unit 103, the MAC packet processing unit 306 receives the UCCH 209 in step 1026. If the uplink SCH 211 is in the frame in step 1027, the MAC packet processing unit 306 Reception processing and ACCH 210 reception processing are sequentially performed in step 1028.

  The configuration of the UCCH 209 is the same as that of the DCCH 208 shown in FIG. 13, but includes the remaining data amount in the non-control information buffer 302 held by the mobile unit 23.

  FIG. 16 is a diagram illustrating an example of the UCCH 209 according to the present embodiment.

  In the control channel buffer 308, the MAC data block of the decoded UCCH 209 and the error detection result related to the MAC data block are recorded for each UCCH 209.

  The retransmission request for the downlink SCH 211 through the UCCH 209 is the same as that through the DCCH 208. When there is a data block that needs to be retransmitted from the downlink non-control information final sequence number in the MAC header and the downlink non-control information retransmission request bitmap, retransmission of the downlink non-control information in the mobile management table 304A shown in FIG. The request sequence number list 3047 is updated. The downlink non-control information transmitted final sequence number 3046 in the mobile management table 304A shown in FIG. 9A is updated with the value of the downlink non-control information final sequence number in the MAC header 2008 of FIG.

  With reference to the error detection result for each DCCH 208, if there is no error, the MAC data block excluding the MAC header and padding is written to the control information buffer 301, and the uplink control information continuous in the mobile management table 304A shown in FIG. The reception failure count 3050 is reset to zero. If there is an error, the MAC data block is not written to the control information buffer, and 1 is added to the uplink control information continuous reception failure count 3050.

  When the processing of the UCCH 209 is completed, the reception processing of the uplink SCH 211 is executed next. The configuration of the uplink SCH 211 is the same as that in FIG. However, the downlink non-control information final sequence number and the downlink non-control information sequence number bitmap in FIG. 14 are an uplink non-control information final sequence number and an uplink non-control information sequence number bitmap, respectively.

  The non-control channel buffer 309 records the decoded MAC data block of the uplink SCH 211 and the error detection result related to the MAC data block for each of the uplink SCH 211 channel and a plurality of MAC data blocks in the uplink SCH 211.

  First, the uplink non-control information final sequence number and uplink non-control information in FIG. 9 are obtained from the uplink non-control information final sequence number and uplink non-control information sequence number bitmap in the MAC header 2003, and the error detection result for each MAC data block. The control information retransmission request sequence number list is updated.

  Next, a segment for the MAC data block for which no error was detected is assembled. Of the MAC data blocks stored in the non-control channel buffer 309, those that can be combined from the beginning to the end of the segment using the MAC data block where the error detection result = no detection is sent to the non-control information buffer 302 When all segments in the write and MAC data block have been written to the non-control information buffer 302, the MAC data block is deleted from the non-control channel buffer 309.

  When the processing of the SCH 211 is completed, the reception processing of the ACCH 210 is executed next.

  FIG. 17 is a diagram illustrating a configuration example of the ACCH 210 according to the present embodiment.

  ACCH 210 includes an ACCH data body 2010. In the present embodiment, at least, the mobile identifier of the transmission source may be transmitted to the fixed radio station 13 via the ACCH 210. In actual operation, information related to mobile authentication may be included in the ACCH 210 from the viewpoint of ensuring security.

  The access control channel buffer 311 records the MAC data block of the ACCH 210 after decoding and the error detection result regarding the MAC data block for each ACCH 210. The ACCH 210 with no error detection result is transferred to the access management unit 307 as it is. If there is an error, nothing is done.

  FIG. 18 is a diagram illustrating a configuration example of the wireless signal processing arithmetic device 103 according to the present embodiment.

  In this embodiment, uplink communication and downlink communication use complementary wireless channels, but all data blocks to be handled have the same coding rate, interleave pattern, modulation method, and number of modulation symbols. The radio station 13 and the mobile unit 23 only need to have the same radio signal processing arithmetic unit 103, and only the part of the radio transmission buffer 106 to be referenced differs depending on the radio channel to be handled.

  The radio signal processing arithmetic device 103 includes processing units 401 to 409 on the transmission side described below. Processing is performed for each data block constituting the wireless channel in the order of the wireless channels shown in FIG.

  The error detection code unit 401 reads the MAC data block written in the wireless transmission buffer 106 by the wireless transmission control arithmetic device 102 and adds an error detection code to the end. For example, a CRC (Cyclic Redundancy Check) code may be used as the error detection code.

  Error correction coding section 402 generates a redundant bit sequence for error correction on the receiving side. For example, convolutional coding may be used.

  The interleave repetition scrambler unit 403 repeats the output of the error correction coding unit 402 so that the number of bits becomes twice the number of DQPSK modulation symbols in the data block. The bit string after repetition is rearranged using an interleave pattern stored in advance in the signal processing memory 108 at the same timing as the program writing. The interleave pattern may be arbitrary, but the rearrangement is desirably random. The interleaved output and the pseudo random number bit string are scrambled by exclusive OR for each bit. The pseudo random number bit string is stored in the signal processing memory 108 in advance, like the interleave pattern.

  The DQPSK modulation unit 404 pairs the scrambled bit string two bits at a time, and inputs π / 4 when input in the order of 0,0, and 3π / 4,1,1 when input as 1,0. If it is input, a phase delta value of 7π / 4 is assigned. As shown in FIG. 6, the previous OFDM symbol in the same logical subcarrier is used as a phase reference, the phase delta value is added to the phase reference, and the result of a 2π modulo operation is used as the phase of the logical subcarrier and the OFDM symbol. Furthermore, this is redefined as a phase reference, and the phase of the next OFDM symbol in the same logical subcarrier is determined repeatedly.

  The resource mapping unit 405 arranges the DQPSK modulation result, the null symbol, and the differential QPSK phase reference symbol as shown in FIG. As for the arrangement of null symbols, a pattern that is not inconsistent with the value of the null symbol arrangement offset in FIG. 8 is stored in the signal processing memory 108 in advance. Similarly, for the differential QPSK phase reference symbol for each subcarrier, a pattern common to the entire system is stored in the signal processing memory 108 in advance.

  The IFFT unit 406 performs IFFT processing on the output of the resource mapping unit for each OFDM symbol.

  The CP adding unit 407 generates a cyclic prefix from the output of the IFFT unit 406 and adds the cyclic prefix to the front of the IFFT output. For example, if the IFFT output is 64 samples and the CP length is 16 samples, the last 16 samples of the IFFT output are extracted as the CP, and a lump of 80 samples in total is generated and output in the order of CP and IFFT output.

  As shown in FIG. 4, the time multiplexing unit 408 time-multiplexes the preamble, the data body, and the guard time. The preamble is stored in the signal processing memory 108 in advance. The data body is the output of the CP adding unit 407.

  The frequency shift unit 409 is a block for realizing frequency hopping, and performs phase shift on the output of the time multiplexing unit according to the frequency channel determination method described in the description of FIG. The offset and step for determining the frequency channel are the frequency hopping offset and the frequency hopping interval shown in FIG. 8, and are set by writing from the radio transmission control arithmetic unit 102 to the register of the radio signal processing arithmetic unit 103. Similarly, the frame writes the value determined by the scheduler 305 into the register of the wireless signal processing arithmetic device 103. Since L is a system default value, it may be recorded in advance in the signal processing memory 108 and referred to by the program or may be incorporated in the program itself. As described in the explanation of FIG. 8, i is a value assigned to each radio channel, and it is preferable to incorporate a conversion formula between the radio channel and i in the program itself. The output of the frequency shift unit 409 is input to the wireless signal transmission / reception device 104.

  The wireless signal processing arithmetic device 103 includes receiving side processing units 410 to 418 described below. As with the transmission side, data blocks are input from the wireless signal transmitting / receiving apparatus 104 in the order of the wireless channels shown in FIG. 3, and processing is executed for each data block constituting the wireless channel.

  The frequency shift unit 410 has the same logic as the frequency shift unit 409 on the transmission side, but performs a phase shift opposite to that on the transmission side.

  The preamble detection unit 411 detects preamble reception timing using a matched filter or the like.

  Based on the preamble timing of the radio channel detected by the preamble detector 411, the FFT unit 412 performs an FFT process on a certain number of samples corresponding to the number of physical subcarriers immediately after the CP of each OFDM symbol in the data body. The frequency domain received signal is acquired.

  The interference noise power estimation unit 413 estimates the interference noise power of each OFDM symbol and each subcarrier based on the null symbol pattern in the signal processing memory 108 that is also referred to on the transmission side. The interference noise power E of the OFDM symbol #ofdm and the subcarrier #sc can be estimated by, for example, averaging as follows.

  N (ofdm, sc) is the interference noise power observed in the OFDM symbol and subcarrier, and is the square sum of the complex I component and the real Q component. α (ofdm, sc) is a function indicating whether it is a null symbol, and 1 is output when it is a null symbol, and 0 is output when it is not a null symbol. a is a value for determining a range to be averaged, and may be arbitrarily determined.

  The demodulation processing unit 414 obtains the likelihood for each bit. As a method for obtaining the likelihood for each bit with respect to the differential PSK modulation, for example, a method disclosed in Non-Patent Document 1 can be adopted.

  The deinterleave scrambler unit 415 first scrambles the output of the demodulation processing unit 414. The same pseudorandom number sequence as that on the transmission side is used, but since the likelihood is a continuous value instead of a bool value, the likelihood is multiplied by +1 when the pseudorandom sequence is 0, and -1 when the pseudorandom sequence is 1. Multiply the likelihood. Thereafter, deinterleaving is performed with reference to the interleave pattern used on the transmission side.

  The likelihood combining unit 416 is a process of combining the repetition and data transmitted multiple times as the same data block with a likelihood level. At the time of synthesis, the likelihood is divided by the noise power estimated by the interference noise power estimation unit 413 to perform weighted synthesis of likelihoods according to the interference noise power. There are three types of data blocks to be combined: all BCHs 207 in the same frame, each DCCH 208 transmitted continuously in R frames, and each UCCH 209 transmitted continuously in R frames.

  Under the condition that DCCH 208 and UCCH 209 have all frames allocated to each mobile unit 23, when R = 4, the initial transmission is when the remainder obtained by dividing frame by 4 is 0, and the same data block is continuously transmitted for 4 frames from that frame. When sending, regarding DCCH 208 and UCCH 209, four consecutive frames are the target of combining between data blocks. Here, R and the timing of initial transmission are recorded in advance in the signal processing memory 108 and are set to be the same between the fixed radio station 13 and the mobile unit 23.

  The error correction decoding unit 417 performs error correction decoding based on the likelihood for each bit output from the likelihood combining unit, makes a hard decision on the decoding result, and outputs a 0, 1 bit string. For example, a Viterbi decoding method may be used as an error correction algorithm.

  The error detection unit 418 performs a CRC check on the input bit string, determines whether or not there is an error, and determines the determination result and the bit sequence obtained by removing the CRC from the input bit sequence as an appropriate wireless channel in the wireless transmission buffer 106. Write to the part.

  FIG. 19 is a diagram illustrating a configuration example of the wireless signal transmission / reception device 104 according to the present embodiment.

  In FIG. 19, the upper side is a transmission side and provides a function of converting a baseband digital signal output from the wireless signal processing arithmetic unit 103 into a high-frequency analog signal. On the other hand, the lower side is a receiving side and provides a function of converting a high-frequency analog signal input from an antenna into a baseband digital signal.

  In this embodiment, the influence of radiation outside the system band and interference from the outside of the system band is not taken into account, and a sudden change in the input level (for example, interference within the system band changes from nothing to presence). Fluctuation) is not considered. For this reason, a band limiting filter for realizing these functions and an AGC (Automatic Gain Control) for automatically controlling the reception gain may be additionally introduced.

  The D / A conversion unit 501 converts the baseband digital signal output from the wireless signal processing arithmetic device 103 into a baseband analog signal. The LPF unit 502 is a low-pass filter used to reduce the level of unnecessary high-frequency components generated after D / A conversion. The orthogonal modulation unit 503 converts the baseband signal into a high frequency signal. The PA unit 504 is a power amplifier for transmitting a high-frequency analog signal wirelessly.

  The LNA unit 506 is a low noise amplifier that amplifies an input signal to a level that allows subsequent processing. The quadrature demodulator 507 converts the high frequency signal into a baseband signal. The LPF unit 508 is a low-pass filter used to reduce the level of unnecessary high-frequency components. The A / D conversion unit 509 converts the baseband analog signal into a baseband digital signal.

  The transmission / reception changeover switch 505 is used for realizing TDD communication within a frame. Since the transmission signal and the reception signal pass through the transmission / reception selector switch 505 in the order shown in FIG. 3, when each wireless channel is a transmission channel, the transmission signal is switched to the transmission side, and when the wireless channel is a reception channel, the transmission side is switched to the reception side. Since the fixed radio station 13 manages the timing of the radio channel, the transmission / reception is always switched at the timing described above. On the other hand, on the mobile unit 23 side, since transmission / reception is switched at a timing synchronized with the radio signal transmitted by the fixed radio station 13, switching is always performed until timing synchronization is established, and transmission / reception is performed according to the timing after synchronization is established. Switch.

  FIG. 20 is a diagram illustrating a configuration example of the wireless transmission control arithmetic device 102 on the moving body 23 side according to the present embodiment.

  In the radio transmission control arithmetic device 102 on the mobile unit 23 side, the usage method of the control information buffer 301 and the non-control information buffer 302 is the same as that of the radio transmission control arithmetic device 102 on the fixed radio station 13 side. The configuration information memory 303 stores the same information as that of the fixed wireless station 13 side, but records the same configuration information as that in FIG. 8 based on the result of reception through the broadcast channel, that is, the content of the broadcast channel buffer 310.

  The mobile management memory 304 has the same contents as in FIG. 9 but records the channel assignment information by reading up and down. However, unlike the fixed radio station 13, only the information of the mobile body 23 is recorded.

  The scheduler 305 is activated at regular intervals (for example, every 100 ms) similarly to the fixed wireless station 13. When the scheduler 305 is activated, the scheduler 305 first refers to broadcast information from the fixed wireless station 13 (FIG. 15) and determines whether there is a wireless channel that can be used by the mobile unit 23. When the mobile object to be allocated regarding the UCCH 209, the SCH 211, or the ACCH 210 explicitly indicates the mobile object 23, the contents of the control information buffer 301, the contents of the non-control information buffer 302, or the mobile object 23 Transmission data is set in the MAC packet processing unit 306 in order to transmit the mobile unit identifier through each wireless channel. Data blocks generated by the MAC packet processing unit 306 are in the formats shown in FIGS. 16, 14, and 17, respectively.

  When the UCCH 209 is transmitted, the data amount remaining in the non-control information buffer 302, that is, the non-control information untransmitted data amount of FIG. 16 is transmitted every time. However, while the same data block is continuously transmitted, it is not necessary to update the data amount because there is a problem in composition on the receiving side.

  Unlike the fixed wireless station 13, the mobile body 23 is in a state where the system timing is indefinite and is not connected to any fixed wireless station 13 immediately after activation. In this case, first, the radio signal processing arithmetic device 103 of the moving body 23 ensures timing synchronization with the fixed radio station 13 based on the preamble reception timing. Next, the mobile unit 23 attempts to receive the broadcast channel (BCH) 207 output from the fixed wireless station 13 that ensures timing synchronization. If ACCH 210 (mobile identifier 0xFFFF) that can be freely used by any mobile unit 23 in the frame is broadcast on broadcast channel 207, mobile unit 23 attempts to transmit ACCH 210. At this time, which channel of ACCH 210 is to be used may be determined freely by mobile body 23 itself. If the transmitted ACCH 210 is accepted by the fixed radio station 13 and it can be confirmed that at least one of the DCCH 208 and the UCCH 209 is assigned to the mobile unit 23 in the broadcast channel, the connection to the fixed radio station 13 is completed. In the present embodiment, the state management is performed by the scheduler 305 itself, and it is determined whether the mobile unit 23 is not connected to the fixed wireless station 13.

  FIG. 21 is a diagram illustrating an operation sequence at the time of handover.

  Consider a mobile unit 23, a fixed radio station 13A in communication with the mobile unit 23, and a fixed radio station 13B as a handover destination. The two fixed radio stations 13 each transmit a broadcast channel to the mobile unit 23 as a normal operation. The mobile unit 23 receives the broadcast channels transmitted from the two fixed radio stations 13 in a wide band, and measures the average received power of all frequency hopping channels and all broadcast channels in the frame.

  Next, based on the measurement result, the average received power related to the broadcast channel hopping pattern of the fixed radio station 13A is used as a reference, and the average power for the hopping patterns other than the fixed radio station 13A is obtained. Then, using the level lower than the reference value by X [dB] as a threshold, the hopping pattern exceeding the threshold is identified with the maximum average received power, and the frequency hopping offset and the hopping interval are transmitted to the fixed radio station 13A via the UCCH 209. .

  When the fixed radio station 13 receives the UCCH 209, the fixed radio station 13 refers to the initially set neighbor list, searches the table using the frequency hopping offset and the hopping interval received by the UCCH 209, identifies the fixed radio station 13B, and Request resource reservation for handover to 13B.

  When receiving the resource reservation request, the fixed wireless station 13B returns a positive response when there is a control channel (DCCH 208, UCCH 209) that can be reserved, and a negative response when there is no reservation. When a positive response is returned, the ACCH 210 dedicated to the handover target mobile unit is continuously secured for a certain time (for example, 1 second), and the allocation information of the ACCH 210 is transmitted by the BCH 207. The response from the fixed wireless station 13B is notified from the fixed wireless station 13A to the moving body 23 by the DCCH 208. Here, when the mobile body 23 receives a negative response, the handover operation may be performed again while being connected to the fixed wireless station 13A.

  When the mobile body 23 receives a positive response, it triggers a handover at its own timing. Specifically, when the average reception power of the hopping pattern of the fixed radio station 13B exceeds the threshold lower by Y [dB] than the average reception power of the fixed radio station 13A at the timing of the continuous transmission of the control system channel, Trigger a handover. In response to the handover trigger, the mobile unit 23 transmits the ACCH 210 dedicated to the handover target mobile unit to the fixed radio station 13B. On the other hand, the fixed radio station 13B allocates a control channel and notifies the mobile unit 23 of the allocation information through the BCH 207, thereby completing the handover.

  Since the mobile unit 23 does not transmit anything to the fixed radio station 13A after the establishment of communication with the fixed radio station 13B, the fixed radio station 13A continuously fails to receive control information from the mobile unit 23. As indicated by 1, the communication is implicitly disconnected.

  When the predetermined time has passed without the control channel assignment information coming from the fixed radio station 13B to the mobile unit 23, the mobile unit 23 determines that the handover has failed and continues communication with the fixed radio station 13A.

  Some functions are added to the system of the first embodiment in order to realize the handover according to the above procedure.

  First, an indicator as to whether there is neighbor FH information and information on the frequency hopping offset and frequency hopping interval observed in the above-described procedure are added to the MAC header of UCCH 209 shown in FIG.

  Second, a broadband reception function is added to the wireless signal processing arithmetic unit 103 of the mobile unit 23. In parallel with the processing of the main signal shown in the first embodiment, the average received power for all frequency hopping channels and the intra-frame BCH 207 is measured, and the measurement result can be referred to from the radio transmission control arithmetic unit 102.

  Third, a function of specifying the frequency hopping offset and the frequency hopping interval of the nearby fixed wireless station 13 from the above-described average received power information is added to the wireless transmission control arithmetic device 102 of the mobile object 23.

  Fourth, a function for transmitting a reservation request message and a response message for a control channel to the mobile object 23 to be handed over to the radio transmission control arithmetic unit 102 of the fixed radio station 13 between the fixed radio stations 13, and a resource reservation process And a table that associates these combinations with nearby fixed wireless stations 13 is added. Further, a function for specifying a nearby fixed radio station 13 corresponding to the combination from the table is added to the radio transmission control arithmetic unit 102 of the mobile unit 23.

  Fifth, an indicator indicating that resource reservation at the neighbor fixed radio station 13 is completed is added to the MAC header of the DCCH 208 shown in FIG.

  Sixth, a function of notifying X [dB] and Y [dB] used for handover-related threshold calculation is added to the data structure of BCH 207 in FIG.

<Example 2>
In the third embodiment, the maintenance terminal device 17 operated by the system operator and the fixed wireless station 13 are connected by a backbone network, and an instruction from the maintenance terminal device 17 is transmitted via the network interface device of the fixed wireless station 13 as a wireless transmission control calculation. The transmission path is expanded in the system of the first embodiment or the second embodiment so as to be transmitted to the scheduler 305 in the apparatus 102.

  The maintenance terminal device 17 directly instructs the scheduler 305 on the communication direction of the SCH 211 shown in FIG. 15 and the non-control system channel allocation information corresponding to the mobile unit identifier, for example, to the mobile unit 23 in an emergency situation. The communication band can be inclined and distributed for instructions and information collection from the mobile unit 23. Even in the situation where the maintenance terminal device 17 directly instructs the scheduler 305, the broadcast channel (BCH) 207, the access control channel (ACCH) 210, and the control system channels (DCCH 208, UCCH 209) are controlled by the autonomous operation of the scheduler 305. Is done.

  The scheduler 305 may have two modes: a mode that operates completely autonomously as in the first and second embodiments, and a mode that follows the maintenance terminal device 17 only for non-control system channel allocation. The device 17 may be managed.

  As described above, according to the embodiment of the present invention, the radio frame transmits at least the control channel (DCCH 208, UCCH 209) for transmitting information used for mobile control and information other than that used for mobile control. Non-control channel (SCH211), broadcast channel (BCH207) for notifying all mobile units 23 of radio control information, and access control used to establish connection from the mobile unit 23 to the fixed radio station 13 The fixed wireless station 13 assigns at least one channel pair of control channel uplink (UCCH 209) and downlink (DCCH 208) to the mobile unit 23 in the radio frame, and includes a non-control channel ( SCH 211) is dynamically switched between uplink and downlink communication directions, and a non-control channel ( CH211) dynamically assigned to the mobile 23. For this reason, since the radio frame can be configured so that the mobile unit 23 to which the non-control system channel is allocated and the communication direction (up and down) can be flexibly changed, a communication band for controlling the mobile unit 23 is continuously provided. On the other hand, it is possible to allocate a large number of communication bands to specific terminals. For example, the communication band can be allocated to the mobile units 23 that need to transmit a lot of non-control system information in an emergency situation. Furthermore, by securing the uplink and downlink channels of the control system to each mobile unit 23, a communication band for controlling the mobile unit 23 can be continuously provided even in an emergency situation. There is no problem in control.

  Further, when non-control system information to be transmitted is generated, the mobile unit 23 uses an uplink non-control system using at least one of the uplink control system channels (UCCH 209) included in the channel pair assigned to the mobile unit 23. Since allocation of the channel (SCH211) is requested to the fixed radio station 13, it is possible to request allocation quickly by effectively utilizing the control channel (UCCH209) that is always allocated.

  The fixed radio station 13 receives the uplink non-control system channel (SCH211) allocation request, or when non-control system information to be transmitted is generated, the mobile unit 23 that allocates the non-control system channel (SCH211) and The uplink or downlink communication direction of the non-control system channel is determined, and the determination result is notified to all the mobile bodies 23 using the broadcast channel (BCH 207), so there is no need to notify the mobile bodies 23 individually, The line usage efficiency can be improved. In addition, the allocation of the non-control channel can also be notified to the mobile unit 23 that is not yet connected to the fixed radio station 13.

  The fixed wireless station 13 receives an instruction from the mobile unit 23 having a high allocation priority and then receives an allocation request for an uplink non-control channel (SCH 211) from the mobile unit 23 or transmits to the mobile unit 23 When non-control system information to be generated is generated, a non-control system channel is preferentially assigned to the mobile body 23. Therefore, an emergency situation occurs and the mobile body 23 needs to transmit a large amount of non-control system information. The communication band can be distributed in a gradient.

  In addition, since the fixed radio station 13 transmits the data block having the same content a plurality of times in the radio frame of the broadcast channel (BCH 207), it can reliably notify the mobile unit 23 of channel assignment, which is important information.

  In addition, since the fixed radio station 13 transmits the data block having the same content a plurality of times at different frequencies within the radio frame of the broadcast channel (BCH 207), the fixed radio station 13 takes the fading countermeasure by the effect of frequency diversity, and uses important information. A certain channel assignment can be reliably notified to the mobile unit 23.

  Each channel is composed of a guard interval, a preamble, and one or a plurality of data blocks. A coding rate, an interleave pattern, a modulation scheme, and the number of modulation symbols are set between channels and between a plurality of data blocks in the same channel. Since they are equal, it is not necessary to have a hardware configuration corresponding to a plurality of systems, and the hardware can be easily configured.

  Each data block includes a phase reference symbol, a null symbol, and a differential QPSK modulation symbol. Therefore, the degree of interference can be measured by the null symbol, and high-speed movement can be handled by the differential QPSK modulation.

  In differential QPSK modulation, a logical frequency index is assigned to the phase reference symbol excluding the null symbol and the differential QPSK symbol, and differential modulation is performed between the symbols having the same frequency index. By modulating between, the error rate can be reduced.

  In addition, when a part or all of the data blocks in the non-control system channel (SCH 211) have failed to be received, the fixed radio station 13 and the mobile unit 23 receive data to be retransmitted on the control system channels (DCCH 208, UCCH 209). Since a block is designated, a control channel (UCCH 209) that is always assigned can be effectively used without providing a dedicated channel for transmitting retransmission information, and overhead can be reduced.

Also,
The fixed radio station 13 determines whether the access control channel operates in a mode in which transmission from all mobile units 23 is permitted or a mode in which transmission from only a specific mobile unit 23 is permitted. Since the determination result is notified to all the mobile bodies 23 using the broadcast channel, the success rate of handover can be improved.

  Similarly to the fixed radio station 13, the mobile body 23 includes a network interface device 101, a radio transmission control arithmetic device 102, a radio signal processing arithmetic device 103, and a radio signal transmission / reception device 104, and the radio transmission control arithmetic device 102. By switching the processing executed by the fixed wireless station 13 and the mobile body 23, it is possible to configure either the fixed wireless station 13 or the mobile body 23, so that the program that operates on the same hardware can be changed. Only the fixed radio station 13 or the moving body 23 can be configured.

  The present invention is not limited to the above-described embodiments, and includes various modifications and equivalent configurations within the scope of the appended claims. For example, the above-described embodiments have been described in detail for easy understanding of the present invention, and the present invention is not necessarily limited to those having all the configurations described. A part of the configuration of one embodiment may be replaced with the configuration of another embodiment. Moreover, you may add the structure of another Example to the structure of a certain Example. In addition, for a part of the configuration of each embodiment, another configuration may be added, deleted, or replaced.

  In addition, each of the above-described configurations, functions, processing units, processing means, etc. may be realized in hardware by designing a part or all of them, for example, with an integrated circuit, and the processor realizes each function. It may be realized by software by interpreting and executing the program to be executed.

  Information such as programs, tables, and files that realize each function can be stored in a storage device such as a memory, a hard disk, and an SSD (Solid State Drive), or a recording medium such as an IC card, an SD card, and a DVD.

  Further, the control lines and the information lines are those that are considered necessary for the explanation, and not all the control lines and information lines that are necessary for the mounting are shown. In practice, it can be considered that almost all the components are connected to each other.

11. Control information transmission device
DESCRIPTION OF SYMBOLS 12 ... Non-control information transmission device 13 ... Fixed wireless station 14 ... Wireless transmission device 15 ... Antenna 16 ... Backbone network 17 ... Maintenance terminal device 21 ... Control information transmission device 22 ... Non-control information transmission device 23 ... Mobile 24 ... Wireless transmission Device 25 ... Antenna 101 ... Network interface device 102 ... Wireless transmission control arithmetic device 103 ... Radio signal processing arithmetic device 104 ... Radio signal transmitting / receiving device 105 ... Packet buffer 106 ... Wireless transmission buffer 107 ... Radio control memory 108 ... Signal processing memory 109 ... Common bus 110 ... Program memory 111 ... Boot processor 201 ... Frame 202 ... Broadcast channel group 203 ... Downlink mobile control information transmission channel 204 ... Uplink mobile control information transmission channel 205 ... Access control channel 206 ... Non-control information shared transmission channel 20 ... broadcast channel 208 ... downlink mobile control information transmission channel 209 ... uplink mobile control information transmission channel 210 ... access control channel 211 ... non-control information shared transmission channel 221 ... preamble 222 ... data 223 ... guard interval 231 ... phase reference symbol 232 ... guard subcarrier and DC subcarrier 233 ... data symbol 234 ... null symbol 241 ... logical subcarrier 301 ... mobile control information buffer 302 ... non-control information buffer 303 ... configuration information memory 304 ... mobile management memory 305 ... scheduler 306 ... MAC packet processing unit 307 ... access management unit 308 ... mobile control channel buffer 309 ... non-control channel buffer 310 ... broadcast channel buffer 311 ... access control channel buffer 401 ... error detection code Unit 402 ... error correction code unit 403 ... interleave repetition scrambler unit 404 ... DQPSK modulation unit 405 ... resource mapping unit 406 ... IFFT unit 407 ... CP addition unit 408 ... time multiplexing unit 409 ... transmission side frequency shift unit 410 ... Reception side frequency shift unit 411 ... Preamble detection unit 412 ... FFT unit 413 ... Interference noise power estimation unit 414 ... Demodulation processing unit 415 ... Deinterleave / scrambler unit 416 ... Likelihood synthesis unit 417 ... Error correction decoding unit 418 ... Error detection 501 ... Digital-analog conversion unit 502 ... Low-pass filter 503 ... Orthogonal modulation unit 504 ... Power amplifier 505 ... Transmission / reception switching unit 506 ... Low noise amplification unit 507 ... Orthogonal demodulation unit 508 ... Low-pass filter 509 ... Analog / digital conversion unit

Claims (14)

A wireless communication method in a wireless communication system using a fixed station and a mobile station,
The radio frame used in the radio communication method includes at least a control channel for transmitting information used for mobile control, a non-control channel for transmitting information other than that used for mobile control, and all the mobile stations. A broadcast channel for notifying radio control information, and an access control channel used for establishing a connection from the mobile station to the fixed station,
The fixed station is
In the radio frame, assign at least one uplink and downlink channel pair of the control channel to the mobile station,
A radio communication method characterized by dynamically switching uplink and downlink communication directions in the non-control channel and dynamically allocating the non-control channel to the mobile station. The wireless communication method according to claim 1,
When the non-control system information to be transmitted is generated, the mobile station allocates an uplink non-control channel using at least one of the uplink control channels included in the channel pair allocated to the mobile station. A wireless communication method characterized by requesting a fixed station. The wireless communication method according to claim 2,
When the fixed station receives the uplink non-control system channel allocation request or when non-control system information to be transmitted is generated, the fixed station allocates the non-control system channel and the uplink or downlink of the non-control system channel. A communication direction, and using the broadcast channel, the result of the determination is notified to all the mobile stations. The wireless communication method according to claim 3,
After receiving an instruction from a mobile station having a high allocation priority, the fixed station receives an uplink non-control system channel allocation request from the mobile station, or non-control system information to be transmitted to the mobile station is generated A wireless communication method characterized by preferentially assigning a non-control channel to the mobile station. The wireless communication method according to claim 1,
The fixed station transmits a data block having the same content a plurality of times in a radio frame of the broadcast channel. The wireless communication method according to claim 5,
The fixed station transmits a data block having the same content a plurality of times at different frequencies in a radio frame of the broadcast channel. The wireless communication method according to claim 1,
Each channel includes a guard interval, a preamble, and one or a plurality of data blocks.
A radio communication method characterized by equalizing a coding rate, an interleave pattern, a modulation scheme, and a modulation symbol number between the channels and between a plurality of data blocks in the same channel. The wireless communication method according to claim 7, comprising:
Each of the data blocks includes a phase reference symbol, a null symbol, and a differential QPSK modulation symbol. The wireless communication method according to claim 8, comprising:
In the differential QPSK modulation, a logical frequency index is assigned to the phase reference symbol and the differential QPSK symbol excluding the null symbol, and differential modulation is performed between the symbols having the same frequency index. . The wireless communication method according to claim 7, comprising:
The fixed station and the mobile station specify a data block to be retransmitted in the control system channel when reception of a part or all of the data blocks in the non-control system channel fails. Wireless communication method. The wireless communication method according to claim 1,
The fixed station determines whether the access control channel operates in a mode in which transmission from all mobile stations is permitted or in a mode in which transmission from only a specific mobile station is permitted. A result of notifying a result to all the mobile stations using the broadcast channel. A wireless communication system in which a fixed station and a mobile station communicate with each other,
Radio frames used in communication between the fixed station and the mobile station are at least a control system channel that transmits information used for mobile control, and a non-control system channel that transmits information other than that used for mobile control, A broadcast channel for notifying radio control information to all the mobile stations, and an access control channel used for establishing a connection from the mobile station to the fixed station,
The fixed station is
A network interface device providing a communication interface function with other systems;
A wireless transmission control arithmetic device that provides a scheduling function and an access control function related to wireless communication transmission;
A radio signal processing arithmetic device that mutually converts a bit sequence transmitted by radio and a baseband digital signal, and provides an error detection and error correction function;
A radio signal transmitting / receiving device that converts a baseband digital signal and a high-frequency analog signal to each other and provides a wireless interface function;
The radio transmission control arithmetic unit allocates at least one uplink and downlink channel pair of the control channel to the mobile station in the radio frame, and dynamically sets uplink and downlink communication directions in the non-control channel. And providing a function of dynamically allocating the non-control channel to the mobile station. The wireless communication system according to claim 12,
The mobile station, like the fixed station, has a network interface device, a radio transmission control arithmetic device, a radio signal processing arithmetic device, and a radio signal transmitting / receiving device,
A wireless communication system, wherein either the fixed station or the mobile station can be configured by switching processing executed by the wireless transmission control arithmetic device between the fixed station and the mobile station. A program for controlling a fixed station in a wireless communication system using a fixed station and a mobile station,
Radio frames used in communication between the fixed station and the mobile station are at least a control system channel that transmits information used for mobile control, and a non-control system channel that transmits information other than that used for mobile control, A broadcast channel for notifying radio control information to all the mobile stations, and an access control channel used for establishing a connection from the mobile station to the fixed station,
The program is
In the radio frame, a procedure for assigning at least one uplink and downlink channel pair of the control channel to the mobile station;
A program for causing the fixed station to execute a procedure of dynamically switching uplink and downlink communication directions in the non-control channel and dynamically allocating the non-control channel to the mobile station.

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