JP2011188382A - Communication method, communication system, base station communication device, and terminal communication device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve a communication speed by efficiently using frequency channels. <P>SOLUTION: A communication device information storage circuit 105 acquires communication device information including a frequency of a clock signal of an analog-digital converter owned by each terminal communication device and the presence or absence of a frequency switching mode, on the basis of a reception signal received from the terminal communication device. A communication method determining circuit 106 allocates the frequency channel of a transmission signal for the terminal communication device on the basis of the communication device information, and determines a modulation system and a coding rate on the basis of the frequency allocation. A data output circuit 100 modulates and codes the data destined to a designated communication opposite party in accordance with the determined modulation system and coding rate. A notice signal inserting circuit 102 inserts a notice signal for notifying each communication opposite party of a frequency and a transmission mode indicating the modulation system and coding rate into a predetermined part of a transmission signal. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a communication method, a communication system, a base station communication apparatus, and a terminal, which use the same frequency channel, spatially multiplex independent signal sequences from a plurality of different transmission antennas, and realize information transmission to a plurality of communication partners The present invention relates to a communication device.

  In recent years, the IEEE802.11g standard, the IEEE802.11a standard, and the like are remarkable as high-speed wireless access systems using the 2.4 GHz band or the 5 GHz band. In these systems, an orthogonal frequency division multiplexing (OFDM) modulation scheme, which is a technique for stabilizing characteristics in a multipath fading environment, is used, and a transmission rate of 54 Mbps at the maximum is realized.

  However, the transmission rate here is a transmission rate on the physical layer. Actually, since the transmission efficiency in the MAC (Medium Access Control) layer is about 50 to 70%, the upper limit of the actual throughput. The value is about 30 Mbps. Furthermore, IEEE 802.11n is scheduled to be standardized in 2010, and aims to realize high-speed communication exceeding 100 Mbps using multiple input multiple output (MIMO) technology.

  However, on the other hand, the communication speed of the wired LAN has been increasing due to the spread of FTTH (Fiber to the home), and it is expected that further increase in the transmission speed will be required in the wireless LAN. The In the approach up to IEEE802.11n, communication is performed using the TDD system, and the target of communication at the same time is a single communication partner.

FIG. 15 is a conceptual diagram illustrating a packet control method for time and frequency channels in a communication method according to the prior art. The communication device serving as the base station communicates using a certain frequency channel (here, F ₂ ), and sends a request to send (RTS) to the terminal communication devices User 1 and User 2 at different times. After receiving the reception preparation completion (Clear to send: CTS), a signal packet is transmitted, and an acknowledgment (Acknowledgment: ACK) is returned from each terminal communication device to complete the communication.

Masahiro Morikura, 802.11 high-speed wireless LAN textbook Quentin H. Spencer, et.al, Zero-Forcing Methods for Downlink Spatial Multiplexing in Multiuser MIMO Channels

In the prior art described above, by assigning different times to two users, a plurality of communication partners are allocated to different times, and transmission to a plurality of communication partners is enabled by time division multiplexing. However, in such a communication system, the base station communication apparatus has a higher frequency ADC (Analog Digital Converter) and DAC (Digital Analog Converter) clock than the terminal communication apparatus, or the ADC and DAC of the terminal communication apparatus. For example, as shown in FIG. 12, even if the four frequency channels F _{1 to} F ₄ can be used, different channels of the same frequency band are used at the same time. Therefore, the frequency channel cannot be used effectively, and the communication speed cannot be increased in proportion to the frequency of the ADC and DAC clock signals of the base station communication apparatus.

  Further, in addition to the case where the base station communication apparatus has an ADC or DAC with a high frequency clock, a communication method for performing transmission at the same time and the same frequency by multi-user MIMO technology has been clarified so far. Absent.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a communication method, a communication system, a base station communication device, and a terminal capable of improving a communication speed by effectively using a frequency channel. It is to provide a communication device.

  In order to solve the above-described problems, the present invention provides a communication in which a base station communication device communicates simultaneously with a plurality of terminal communication devices including an analog-digital conversion device (ADC) or a digital-analog conversion device (DAC) of a received signal. In the method, the terminal communication device includes communication device information including at least one of frequency information of an ADC or DAC clock signal included therein and information indicating presence / absence of an instantaneous switching mode of a reference signal to be down-converted, A communication device information notifying step for notifying a base station communication device; and a communication in which the base station communication device extracts each communication device information notified from each terminal communication device and stores the extracted each communication device information A device information storing step, and the base station communication device is configured to receive each of the clocks included in the extracted communication device information. Frequency channel assignment determination step for determining frequency channel assignment to each terminal communication device based on frequency information of a signal and information indicating presence / absence of each frequency switching mode, and the base station communication device is determined Based on the allocation of each frequency channel, a transmission mode determination step for determining a transmission mode consisting of a modulation scheme and a coding rate at the time of data transmission to the terminal communication device, the base station communication device for the terminal communication device, A transmission step of converting data to be transmitted based on the determined modulation scheme, coding rate, and frequency channel assignment, and transmitting the data to each of the terminal communication devices.

  According to the present invention, in the above invention, the base station communication device estimates each channel information with the terminal communication device based on a received signal received from each terminal communication device; and A communication device information storage step for storing the estimated channel information and communication device information for each terminal communication device, and the base station communication device based on the extracted each communication device information, A frequency allocation / multiuser MIMO mode determination step for determining a multiuser MIMO mode for performing frequency channel allocation and spatial multiplexing for use in data transmission to the base station, and the base station communication apparatus, based on each estimated channel information, A transmission weight calculation step for calculating each transmission weight value for data transmission of the terminal communication device. And the base station communication device converts data to be transmitted based on the determined modulation scheme, coding rate, frequency channel allocation, spatial multiplexing mode, and transmission weight value, and each terminal communication A transmission step for transmitting data to the apparatus may be further included.

  According to the present invention, in the above invention, the base station communication device transmits a channel transmission request signal including the determined allocation of each frequency channel to the terminal communication devices. A channel transmission request signal transmission step, a frequency channel assignment extraction step in which the terminal communication device extracts a frequency channel assignment to the terminal communication device from the channel transmission request signal, and the terminal communication device is extracted. When the frequency channel assignment is outside the frequency channel currently receiving data, the ADC or the DAC performs the conversion by changing the frequency of the reference signal used for frequency conversion based on the extracted frequency channel assignment. A frequency changing step of changing a frequency channel to be performed, and the terminal communication After receiving the data on the changed frequency channel and confirming that the data reception from the base station communication device is completed, the confirmation response signal to the base station communication device is changed. Acknowledgment signal transmission step for transmitting by channel, and after the transmission of the acknowledgment signal, the terminal communication device returns to the frequency channel before changing the frequency channel or before changing the frequency of the clock signal You may make it further provide the frequency return step which returns to a frequency.

 According to the present invention, in the above invention, the terminal communication device is ready for communication informing that the terminal communication device is ready to receive data after the frequency channel assignment extraction step or the frequency change step. A communication preparation completion notification step of transmitting a notification signal to the base station communication device may be further provided.

  According to the present invention, in the above-described invention, the base station communication device may determine which frequency channel to use in the transmission request signal for the base station communication device to notify the terminal communication device of the determined frequency channel assignment. The method may further include a step of including a pilot signal that specifies whether to transmit the confirmation response signal.

  According to the present invention, in the above invention, when the base station communication apparatus multiplexes the data of the plurality of terminal communication apparatuses on the determined one frequency channel, the base station communication apparatus In response to the transmission request signal for notifying the determined frequency channel, the transmission weight calculation unit for the terminal communication device calculated when transmitting the confirmation response signal or the communication preparation completion notification signal. You may make it further provide the step of including delay amount information which designates delay time.

  According to the present invention, in the above invention, when the frequency channel allocation determining step of the base station communication apparatus multiplexes data of the plurality of terminal communication apparatuses on the determined one frequency channel, the base station communication apparatus sets between the frequency channels The terminal communication devices having ADCs or DACs having the same clock signal frequency may be controlled to be multiplexed on the same frequency channel so that the guard band region is reduced.

  According to the present invention, in the above invention, in the frequency channel assignment determination step, at least one of the plurality of terminal communication devices performing transmission is directed to the plurality of terminal communication devices simultaneously on the same frequency channel. When there is no information on the data multiplexing method, frequency channels are allocated so that other terminal communication devices can simultaneously multiplex data on the same frequency channel other than the frequency channels supported by the terminal communication device. You may do it.

  In order to solve the above-described problem, the present invention communicates simultaneously with a plurality of terminal communication devices in which a base station communication device includes an analog-digital conversion device (ADC) or a digital-analog conversion device (DAC) of a received signal. In the communication system, the terminal communication device includes communication device information including at least one of frequency information of an ADC or DAC clock signal included therein and information indicating presence / absence of an instantaneous switching mode of a reference signal to be down-converted. A notification signal transmission circuit for notifying the base station communication device, wherein the base station communication device extracts each communication device information notified from each terminal communication device, and stores the extracted each communication device information Communication device information storage unit, and frequency information of each clock signal included in each stored communication device information Based on the information indicating the presence / absence of each frequency switching mode, allocation of each frequency channel at the time of data transmission to each terminal communication device is determined, and based on the determined allocation of each frequency channel, to the terminal communication device A communication method determining circuit for determining a transmission mode composed of a modulation scheme and a coding rate at the time of data transmission, and data to be transmitted based on the determined modulation scheme, coding rate, and frequency channel assignment to the terminal communication device A transmission signal conversion circuit that converts the transmission signal, a radio unit that converts the converted transmission signal into a transmission frequency, and an antenna that performs transmission.

  In order to solve the above-described problems, the present invention provides a base station communication that simultaneously communicates with a plurality of terminal communication devices including an analog-digital conversion device (ADC) or a digital-analog conversion device (DAC) of a received signal. In the apparatus, a channel information estimation circuit for estimating channel information from a signal transmitted from each terminal communication apparatus, and a communication apparatus information storage for storing each communication apparatus information and channel information notified from each terminal communication apparatus Data for each terminal communication device based on circuit, frequency information of each clock signal included in each stored communication device information and information indicating presence / absence of each frequency switching mode, channel information, or both Determine the assignment of each frequency channel at the time of transmission, and assign the determined frequency channel. A communication method determining circuit for determining a transmission mode comprising a modulation scheme and a coding rate at the time of data transmission to the terminal communication device, and the determined modulation scheme, coding rate, and the like for the terminal communication device; A transmission signal conversion circuit that converts data to be transmitted based on frequency channel assignment, a radio unit that converts the converted transmission signal into a frequency for transmission, and an antenna that performs transmission are provided.

  In order to solve the above-described problem, the present invention provides a terminal communication device that communicates with a base station communication device and includes an analog-digital conversion device (ADC) or a digital-analog conversion device (DAC) of a received signal. A transmission request extracting circuit for acquiring a designated frequency channel from the base station communication apparatus, and an instantaneous reference signal frequency switching circuit for switching the frequency to receive the designated frequency channel are provided.

  According to the present invention, the base station communication device is notified of the communication device information on the terminal communication device side, such as the communication partner clock information, the presence / absence of the multi-user MIMO mode, the presence / absence of the frequency switching mode, and the like based on the communication device information. Thus, by determining the assignment of the frequency channel used for communication, the modulation method and the coding method, the communication speed can be improved by effectively using the frequency channel.

It is a block diagram which shows the structural example of the base station communication apparatus by 1st Embodiment of this invention. It is a block diagram which shows the structural example of the terminal communication apparatus by this 1st Embodiment. It is a conceptual diagram for demonstrating the control method by this 1st Embodiment. It is a conceptual diagram for demonstrating the control method by this 1st Embodiment. It is a conceptual diagram for demonstrating the control method by this 1st Embodiment. It is a conceptual diagram for demonstrating the control method by this 1st Embodiment. It is a block diagram which shows the structural example of the base station communication apparatus by 2nd Embodiment of this invention. It is a conceptual diagram for demonstrating the control method by this 2nd Embodiment. It is a conceptual diagram for demonstrating the control method by this 2nd Embodiment. It is a conceptual diagram for demonstrating the control method by this 2nd Embodiment. It is a conceptual diagram for demonstrating the determination method of the allocation method of the frequency channel by 2nd Embodiment. It is a part of communication flow of 1st Embodiment of this invention. It is a part of communication flow of 2nd Embodiment of this invention. It is a part of communication flow with the terminal communication apparatus and base station communication apparatus of 1st Embodiment or 2nd Embodiment of this invention. It is a conceptual diagram which shows the control method of the packet with respect to the time and frequency channel in the communication system by a prior art.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[First Embodiment]
First, a first embodiment of the present invention will be described. FIG. 1 is a block diagram showing a configuration example of a base station communication apparatus according to the first embodiment of the present invention. The base station communication apparatus includes a data output circuit 100, a transmission signal conversion circuit 101, a notification signal insertion circuit 102, radio units 103-1 to 103-M _t , antennas 104-1 to 104-M _t , and a communication apparatus information storage circuit 105. , And a communication method determination circuit 106.

The data output circuit 100 generates data to be transmitted to the terminal communication device, and receives communication method information (modulation method / coding method) output from the communication method determination circuit 106. The data output circuit 100 outputs data to be transmitted and communication method information to the transmission signal conversion circuit 101.
The transmission signal conversion circuit 101 receives the data output from the data output circuit 100 and communication method information, performs interleaver, modulation and error correction coding on the received data according to the communication method information, and performs orthogonal wave division multiplexing or The signal is converted into a single carrier transmission method, and the converted signal is output to the notification signal insertion circuit 102.

The notification signal insertion circuit (notification signal insertion unit) 102 receives the converted signal output from the transmission signal conversion circuit 101, and communicates with the terminal communication apparatus which is each communication partner at a predetermined position with respect to the received signal. performing frequency, and inserts a notification signal for notifying the transmission mode or the like representing the modulation scheme and coding rate, and outputs a transmission signal by inserting a notification signal to the radio unit 103-1 to 103-M _t.

Radio unit (transmitting unit, receiving unit) 103-1 to _{103-M t} converts the transmission signal from the notification signal insertion circuit 102, the frequency to be transmitted, and transmits the antenna 104-1 to _{104-M t.} The radio unit 103-1 to _{103-M t} includes ADC for receiving, and the DAC. Further, the radio units 103-1 to 103 -M _t convert the signals received by the antennas 104-1 to 104 -M _t into digital signals using the ADC, further convert them into baseband signals, and then receive signals Is output to the communication information device information extraction circuit 105. Further, the radio units 103-1 to 103 -M _t convert the digital signal from the notification signal insertion unit 102 into an analog signal using a DAC and transmit the analog signal using the antennas 104-1 to 104 -M _t . That is, the wireless unit 103-1 to _{103-M t,} and an antenna 104-1 to _{104-M t} transmits and receives radio signals.

Communication device information storage circuit (communication device information storage unit) 105 receives a reception signal by the radio unit 103-1 to 103-M _t is output, extracting the communication device information from the received signal received, extracted communication device information Is output to the communication method determination circuit 106. Here, the communication device information refers to a signal including at least one of the frequency of the ADC clock signal used by the communication device and the presence / absence of the frequency switching function.

A communication method determination circuit (frequency channel allocation determination unit, modulation scheme / coding rate determination unit) 106 receives communication device information output from the communication device information storage circuit 105, and uses the received communication device information to determine a frequency channel used for communication. Allocation, modulation scheme / encoding scheme, and output to the data output circuit 100 and the notification signal insertion circuit 102.
In addition, the communication content determination unit in the claims includes the data output circuit 100, the transmission signal conversion circuit 101, and the communication method determination circuit 106, and the transmission request unit includes the notification signal insertion circuit 102 and the communication method determination circuit 106. It consists of and.

FIG. 2 is a block diagram illustrating a configuration example of the terminal communication device according to the first embodiment. Terminal communication device, the notification signal extraction circuit 201, the reception signal decoding circuit 202, the radio unit 203-1 to _{203-M r,} antennas 204-1 through _{204-M r,} the instantaneous reference signal frequency switching circuit 205, notification signal transmitter circuit 206 and a transmission request extraction circuit 207.

The notification signal extraction circuit 201 receives the decoded signal output from the reception signal decoding circuit 202, extracts the notification signal from the received signal, and outputs the extracted notification signal to the transmission request extraction circuit 207.
Receiving signal decoding circuit 202 receives the received signal by the radio unit 203-1 to _{203-M r} is output, decodes the received signal received, and outputs the decoded signal to the notification signal extraction circuit 201.

Radio unit (second transmitting unit, a second receiving unit) 203-1 to _{203-M r} includes ADC for receiving, and the DAC. ADC, compared signal antenna 204-1 through _{204-M r} has received, and outputs the down-converted in frequency to the instantaneous reference signal frequency switching circuit 205 is determined by converting the digital signal to the reception signal decoding circuit 202. DAC converts digital signals from notification signal transmitter circuit 206 (notification signal) to an analog signal transmitted by the antenna 204-1 through _{204-M r.} That is, the antenna 204-1 through _{204-M r,} and the radio unit 203-1 to _{203-M r} transmits and receives radio signals. The radio unit 203-1 to _{203-M r} receives the frequency switching information output by the instantaneous reference signal frequency switching circuit 205, ADC based on the received frequency switching information, and switches the reference frequency of the DAC.

Instantaneous reference signal frequency switching circuit (frequency switching section) 205 receives the communication information output by the transmission request extraction circuit 207, based on the received communication information, for down-conversion using the wireless unit 203-1 to _{203-M r} and changing the frequency of the reference signal, and outputs the frequency information to change the radio unit 203-1 to _{203-M r.} At this time, and notifies the frequency switching completion to the notification signal transmitting circuit 206 from the instantaneous reference signal frequency switching circuit 205 or the radio unit 203-1 to 203-M _r, based on this signal, the notification signal transmits the reception ready signal You may make it transmit from the circuit 206. FIG.

The notification signal transmission circuit (notification signal transmission unit) 206 receives the communication device information output from the transmission request extraction circuit 207, and when the received communication device information includes its own terminal communication device information, a reception preparation completion notification signal and outputs the generated reception preparation completion notification signal to the radio unit 203-1 to _{203-M r.} In addition, the notification signal transmission circuit 206 is a maximum frequency of ADC and DAC clock signals for transmission / reception of the terminal communication device, the presence / absence of the instantaneous reference signal frequency switching circuit 205, the reception signal decoding circuit 202 is MIMO communication, generates information of its own terminal communication device regarding whether to correspond to the user MIMO communication may be performed to transmit via the radio unit 203-1 to 203-M _r to the base station communication device. Further, the transmission request extraction circuit 207 detects the frequency channel used for the signal to the terminal communication device from the communication device information and outputs it to the reception signal decoding circuit 202, whereby the reception signal decoding circuit 202 is inputted. It is also possible to receive only the signals of some specified frequency channels among the received signals.

  The transmission request extraction circuit (transmission request extraction unit) 207 receives the notification signal output from the notification signal extraction circuit 201, extracts communication device information from the received notification signal, and extracts the extracted communication device information from the notification signal transmission circuit 206. It outputs to the instantaneous reference signal frequency switching circuit 205.

Next, a specific control method according to the first embodiment will be described with reference to FIGS.
3 to 6 are conceptual diagrams for explaining the control method according to the first embodiment. As an example, a system in which _four frequency channels F _{1 to} F ₄ (carrier frequency) exist with F (MHz: frequency bandwidth) per channel is used. For example, each standard of IEEE802.11a, IEEE802.11b, and IEEE802.11g is a system of F = 20 MHz.

3 to 6, U or D characters added to the lower right of each block indicate Uplink and Downlink, Uplink is a signal transmitted by a user as a communication partner, and Downlink is a base station. Represents a signal transmitted by a communication device. P is a pilot signal transmitted from the base station communication apparatus before data. Further, as a prerequisite, the primary channel is a frequency channel F ₂ is set.

  In FIG. 3, it is assumed that the base station communication apparatus has an ADC and a DAC that cover two frequency channels (operation clock of ADC and DAC ≧ 2F), and supports one frequency channel as a communication partner. This shows a communication method between the terminal communication device User1 (ADC and DAC operation clock = F) and the terminal communication device User2 (ADC and DAC operation clock = 2F) supporting two frequency channels.

Since User1 frequency band (frequency of the operation clock) is F, for example, User1 is a case of a terminal communication device 802.11a standard, can only receive and decode at any one frequency channel of the frequency channel _F 1 to F ₄ . On the other hand, when User 2 is a terminal communication apparatus having a reference signal frequency (clock signal frequency) 2F of 40 MHz according to 802.11n or a newer standard, it can receive and decode frequency channels for two channels.
First, the notification signal transmission circuit 206 of the terminal communication device User2 generates a signal including the operation clock frequency 2F of the terminal communication device itself and information (F ₃ ) of the frequency channel used as the secondary, and the generated signal is transmitted to the radio unit. and outputs it to the _{203-1~203-M r.} Here, the notification signal transmitter circuit 206 may convey a signal to tell without frequency switching function to the radio unit 203-1 to 203-M _r, that there is no signal to communicate the presence of a frequency switching function, the frequency switching You may make it respond | correspond to the absence of a function.

Then, the radio unit 203-1 to _{203-M r} of User2 is the absence of received operating clock frequency information (2F) and the used frequency channel information or reference signal frequency band and the used frequency channel information, and switching functions a signal containing, for transmission via at least one antenna 204-1 through _{204-M r} to the base station communication apparatus. Alternatively, rules for using secondary (second), tertiary (third), and quaternary (fourth) frequency channels are determined in advance for the primary frequency channel, and the secondary, third, and third frequency channels are determined in advance. The notification of 4 frequency channels can be omitted. For example, when the frequency channel used by the primary is 5.00 GHz, the second frequency channel (secondary) is 5.02 GHz and the third frequency is used as a rule for using the second to fourth frequency channels. By predetermining that the channel is 4.98 GHz, the fourth frequency channel is 5.04 GHz, etc., the base station communication device only knows the frequency of the primary frequency channel and the clock used, and the frequency of the remaining frequency channel is determined. I can know.

Then, the base station communication apparatus, a frequency channel F _2, the channel transmission request signal; transmitting the (CR Channel request). The channel transmission request signal, a signal notifying that perform future communication to the terminal communication device User1 and User2, signal notifying that the communication is performed frequency channel _{F 2} and User1, frequency channel _{F 3} and User2 A signal for notifying that communication is performed is included. Since the frequency channel F ₂ is a primary channel, if the base station communication device transmits on the frequency channel F ₂ , both the terminal communication device User 1 and User 2 can receive it.

Terminal radio unit 203-1 to _{203-M r} of the communication device User1 has an antenna 204-1 through _204-M via the _r receives the received signal at the frequency channel _{F 2,} the received signal a signal received decoding circuit 202 Output to. Next, the reception signal decoding circuit 202 receives the received signal by the radio unit 203-1 to _{203-M r} is output, decodes the received signal received, and outputs a reception signal decoded in the notification signal extraction unit 201. Next, the notification signal extraction unit 201 receives the decoded reception signal output from the reception signal decoding circuit 202, extracts the notification signal from the received decoded reception signal, and transmits the notification signal to the own terminal communication device. Detect that. Then, the radio unit 203-1 to _{203-M r} of the signal is transmitted User1, shown as data to User1 in Figure 3, receives the data using the frequency channel _{F 2} based on the received communication device information and, after the completion of data reception, based on the communication device information received from the notification signal transmitter circuit 206, it sends an acknowledgment ACK1 to the base station communication apparatus using a frequency channel F _2.

On the other hand, the terminal communication device User2 has a bandwidth of 2F, can receive frequency channel _{F 2} and _{F 3.} Terminal communication device User2 receives channel transmission request CR1 signal on the frequency channel _{F 2} similarly to the terminal communication device User1. Then, the transmission request extraction circuit 207 extracts a channel transmission request signal CR1 that is communication apparatus information for the terminal communication apparatus from the received notification signal, and outputs the extracted communication apparatus information to the reception signal decoding circuit 202. When the signal shown as data to User2 is transmitted in FIG. 3, the radio unit 203-1 to _{203-M r} receives data using the frequency channel _{F 2} and F ₃ on the basis of the received communication device information The received data is output to the received signal decoding circuit 202. Then, the reception signal decoding circuit 202 decodes the data of the pre-frequency channel of the transmission request extractor 207 F ₃ which is specified in the. After data reception is completed, the presence or absence of an error is checked. If it is confirmed that there is no error, the reception signal decoding circuit 202 notifies the notification signal transmission circuit 206 of normal reception, and after receiving notification of normal reception, notification signal transmitter circuit 206 transmits an acknowledgment ACK2 to the base station communication apparatus using a frequency channel F _3.
By controlling the terminal communication device in this way, data can be transmitted and received simultaneously using two frequency bands, and the communication speed can be increased.

Alternatively, the case where the operation clock of the terminal communication device User2 is F and the frequency switching function is provided can be described with reference to FIG. Here, the terminal communication device User1 assumes that the operation clock is F as in the above. In this case, the notification signal transmitter circuit 206 of the terminal communication device User2 is transmitted from antennas 204-1 through _{204-M r} via the radio unit 203-1 to _{203-M r,} the presence of the frequency switching function in the base station communication device To do. When communicating downlink, base station communication apparatus transmits the channel transmission request CR1 specifying the use of frequency channels _{F 3} to the frequency channel _F 2, User2 to User1. The terminal communication device of User1 receives a signal by the same operation as that at the time of reception of the reception signal described above.

Further, the terminal communication device User2 extracts a notification signal in the notification signal extraction circuit 201 from the reception signal decoded by the reception signal decoding circuit 202, and from the extracted channel transmission request signal CR1 in the transmission request extraction circuit 207. data to User2 is detected to be transmitted using the frequency channel F _3. The transmission request extraction circuit 207 outputs communication information indicating that communication using the frequency channel F ₃ is performed to the instantaneous reference signal frequency switching circuit 205 and the notification signal transmission circuit 206. Next, the instantaneous reference signal frequency switching circuit 205 receives the communication information output by the transmission request extraction circuit 207, based on the received communication information, the frequency of receiving data to the wireless unit 203-1 to _{203-M r} the channel time _{T 1} is switched from _{F 2} to _{F 3.}
Then, the radio unit 203-1 to _{203-M r} receives data on the frequency channel _{F 3.} After the data reception is completed, the reception signal decoding circuit 202 checks whether there is an error. If the reception is normal, the notification signal transmission circuit 206 notifies the notification signal transmission circuit 206 of the normal reception. After receiving the notification of the normal reception, the notification signal transmission circuit 206 generates an ACK signal, via the radio unit 203-1 to _{203-M r,} sends an acknowledgment ACK2 to the base station communication apparatus using a frequency channel _{F 3.} Further, after the transmission acknowledgment ACK2, radio unit 203-1 to _{203-M r} of the terminal communication device User2 returns switches the frequency channel at time _{T 2,} the _{F 3} to the frequency band _{F 2} primary.

Further, an operation clock 2F terminal communication device User2, when having received the frequency channel F ₁ and F _2, in accordance with the frequency channel change information output by the instantaneous reference signal frequency switching circuit 205, frequency channel F ₃ it may be switched to the frequency of the reference signal at time T ₁ as employed. After receiving the data, the terminal communication device User1 sends an acknowledgment ACK1 to the base station communication device as a reception completion on the frequency channel _{F 2,} the terminal communication device User2, the base station an acknowledgment ACK2 on the frequency channel _{F 3} Send to communication device. Furthermore, after acknowledgment ACK2 transmission, the instantaneous reference signal frequency switching circuit 205 of the terminal communication device User2 can also switch back to a secondary frequency channel in time _{T 2,} the _{F 3} to _{F 1.}

Incidentally, an example has been described of transmitting terminal communication device User1 and User2 channel transmission request CR1 only transmits two a channel transmission request CR1 for User1 for User2 channel transmission request CR2 different timings on the frequency channel _{F 2} You may do it. Furthermore, when the operation clock 2F that terminal communication device User2 can receive frequency channel _{F 2} and _{F 3} at the same time, the channel transmission request CR1 is transmitted using the frequency channel _{F 2,} the channel transmission request CR2 is frequency channel _{F 3} May be used for transmission (CR2 surrounded by a dotted line in FIG. 3).

  Next, after receiving the channel transmission request CR, the control method of FIG. 4 transmits from the terminal communication apparatuses to the base station communication apparatus as a channel reception preparation completion notification CTS (Clear to send) indicating that reception is possible. Thus, the switching of the frequency channel or the like is completed, and notification that reception and demodulation preparations are completed.

The transmission request extraction unit 207 of the terminal communication device User1 extracts from the channel transmission request CR1 and notifies the notification signal transmission circuit 206 of it. Notification signal transmitter circuit 206 transmits the channel reception preparation completion notification CTS1 via at least one radio unit 203-1 to _{203-M r} and antenna 204-1 through _{204-M r} to the base station communication apparatus. When the data to User1, shown in Figure 4 is transmitted, the radio unit 203-1 to _{203-M r} receives data using the frequency channel _{F 2,} after the completion of data reception, the frequency channel _{F 2} using Confirmation response ACK1 is transmitted to the base station communication apparatus.

On the other hand, the terminal communication device User2 has a bandwidth of 2F, can receive frequency channel _{F 2} and _{F 3.} In this case, the terminal communication device User2 receives channel transmission request CR1 signal in the same frequency channels and _{F 2} and the terminal communication device User1. Then, the transmission request extraction circuit 207, the received and extracted from the notification signal channel transmission request signal CR1 which is a communication device information for the own-terminal communication device, the received signal communication information that is communicated using a frequency channel F ₃ is performed The data is output to the decoding circuit 202. From the channel transmission request signal CR1 is this communication information, because it contains a signal terminal communication device User2 receives data using the frequency channel _{F 3,} the radio unit 203-1 to _{203-M r} is the frequency channel transmitting channel reception preparation completion notification CTS2 to the base station communication device F _3. When the signal shown as data to User2 is transmitted in FIG. 4, the radio unit 203-1 to _{203-M r} outputs the received signal in the frequency channel _{F 2} and _{F 3} to the reception signal decoding circuit 202. Since the received signal decoding circuit 202 which is notified of the communication information from the pre-transmission request extracting circuit 207 performs decoding only the received signal of the frequency channel F _3. After completion of data reception, the presence / absence of an error is checked, and if normal reception without error is confirmed, the reception signal decoding circuit 202 notifies the notification signal transmission circuit 206 of normal reception. Notification signal 206 via the radio unit 203-1 to _{203-M r,} sends an acknowledgment ACK2 to the base station communication apparatus using a frequency channel _{F 3.} That is, when two frequency bands of frequency channels F ₂ and F ₃ are used, a frequency band of 2F is required. After receiving channel transmission request CR1 on frequency channel F ₂ which is the primary frequency, a channel transmission request is received. based on CR1, User1 sends a channel reception preparation completion notification CTS1 on the frequency channel _{F 2,} receives the data, User2 sends a channel reception preparation completion notification CTS1 on the frequency channel _{F 3,} receives the data.

Alternatively, the case where the operation clock frequency of the terminal communication device User2 is F and the frequency switching function is provided can be described with reference to FIG. Here, the terminal communication device User1 is assumed to have an operation clock frequency F as described above. In this case, the notification signal transmitter circuit 206 of the terminal communication device User2 from antenna 204-1 through _{204-M r} via the radio unit 203-1 to _{203-M r,} in there the base station communication device of a frequency switching function Send. When communicating downlink, base station communication apparatus transmits the channel transmission request CR1 specifying the use of frequency channels _{F 3} to the frequency channel _F 2, User2 to User1. The notification signal extraction circuit 201 of the terminal communication device User2 extracts the notification signal from the reception signal decoded by the reception signal decoding circuit 202, and outputs the extracted notification signal to the transmission request extraction circuit 207. Then, the transmission request extracting circuit 207, from the extracted channel transmission request signal CR1, data to User2 is detected to be transmitted using the frequency channel F _3.

The transmission request extraction circuit 207 outputs communication information indicating that communication using the frequency channel F ₃ is performed to the instantaneous reference signal frequency switching circuit 205 and the notification signal transmission circuit 206. Next, the instantaneous reference signal frequency switching circuit 205 receives the communication information output by the transmission request extraction circuit 207, based on the received communication information, the frequency of receiving data to the wireless unit 203-1 to _{203-M r} the channel at time _{T 1} is switched from _{F 2} to _{F 3.} After switching is finished, the notification signal transmitter circuit 206 generates a CTS2, then via the radio unit 203-1 to _{203-M r,} the CTS2 from the antenna 204-1 through _{204-M r} in frequency channel _{F 3} Send.
Next, when the data to User2 shown in Figure 4 is transmitted, the radio unit 203-1 to _{203-M r} receives data on the frequency channel _{F 3.} After the data reception is completed, the reception signal decoding circuit 202 checks whether there is an error, and if it is normal reception, notifies the notification signal transmission circuit 206 of normal reception. Further, after receiving the notification of normal reception, the notification signal transmitter circuit 206 generates an ACK signal, via the radio unit 203-1 to _{203-M r,} the base station an acknowledgment ACK2 using frequency channels _{F 3} Send to communication device. Further, after the transmission acknowledgment ACK2, radio unit 203-1 to _{203-M r} of the terminal communication device User2 returns switches the frequency channel at time _{T 2,} the _{F 3} to the frequency band _{F 2} primary.

Incidentally, an example has been described of transmitting terminal communication device User1 and User2 channel transmission request CR1 only transmits two a channel transmission request CR1 for User1 for User2 channel transmission request CR2 different timings on the frequency channel _{F 2} You may do it. Furthermore, when the operation clock 2F that terminal communication device User2 can receive frequency channel _{F 2} and _{F 3} at the same time, the channel transmission request CR1 is transmitted using the frequency channel _{F 2,} the channel transmission request CR2 is frequency channel _{F 3} May be transmitted (CR2 (c41) surrounded by a dotted line in FIG. 4).

Next, as shown in FIG. 5 (a), the terminal communication device User2 using frequency channel F ₂ is the primary frequency band, from the reply channel reception preparation completion notification CTS2, frequency channel at time T ₁ the may be switched from _{F 2} based on the channel transmission request CR1 to _{F 3.} In this way, when the frequency switching time is not in time for the channel transmission request CR (when a predetermined time is required for stabilization after frequency switching), first, a channel reception preparation completion notification is made. It can be controlled to switch after transmitting the CTS. Although CTS1 in FIG. 5 (a) are described in later than _{T 1,} may be transmitted before the previous and CTS2 _{T 1.}
Incidentally, an example has been described of transmitting terminal communication device User1 and User2 channel transmission request CR1 only transmits two a channel transmission request CR1 for User1 for User2 channel transmission request CR2 different timings on the frequency channel _{F 2} You may do it. Furthermore, in the case of F = 40 MHz to the terminal communication device User2 can receive frequency channel _{F 2} and _{F 3} at the same time, the channel transmission request CR1 is transmitted using the frequency channel _{F 2,} the channel transmission request CR2 is frequency channel _{F 3} May be used for transmission (CR2 (c51) surrounded by a dotted line in FIG. 5A).

Further, as shown in FIG. 5 (b), the data to be transmitted into fragments configuration, the terminal communication device User2 starts frequency switching at time _{T 0,} and for a time _T 0 through T _1, the frequency channel _{F 2} Receive data with. The terminal communication device User2, by receiving the data using the frequency channel F ₃ at the back of the block, it is also possible to provide sufficient time for frequency switching to the terminal communication device User2.

Although an example in which only the channel transmission request CR1 is transmitted to the terminal communication apparatuses User1 and User2 has been described, _two channel transmission requests CR1 for User1 and two channel transmission requests CR2 for User2 are transmitted at different timings in the frequency channel F2. You may make it do. Furthermore, when the operation clock 2F that terminal communication device User2 can receive frequency channel _{F 2} and _{F 3} at the same time, the channel transmission request CR1 is transmitted using the frequency channel _{F 2,} the channel transmission request CR2 is frequency channel _{F 3} May be used for transmission (CR2 (c53) surrounded by a dotted line in FIG. 5B). In this case, the terminal communication device User2 is a fragment configuration data may be received from time _{T 0} in frequency channel _{F 3} (data (c54 surrounded by the dotted line in FIG. 5 (b))). In this way, it is also possible to correct the frequency shift and the clock shift to some extent from the known signal in the c54 signal. In addition, the timing of T ₁ at which the frequency channel of F ₃ is started can be set after an arbitrary number of fragment data. Or decodes only the known signal portion of the signal to the other terminal communication devices, such as c54, when it is confirmed to be received by the default quality, ACK2, and transmitted using the frequency channel F ₃ , After confirming the ACK2, the T ₁ set by the base station communication apparatus, may start sending data to User2.

Ona, 4, channel transmission request CR2 in FIG. 5, although the User1 and User2 may not be received, obtains a transmission right, NAV (Network allocation vector) to construct a packet in the frequency channel _{F 3} The effect of creating a transmission prohibited section can be expected. If this is not necessary, the signal can be omitted because there is no communication partner.

  Next, in FIG. 6, it is assumed that the base station communication apparatus has an ADC and a DAC that cover three or more frequency channels (operation clock of ADC and DAC ≧ 3F). A communication method between a terminal communication device User1 (ADC and DAC operation clock = F) that supports a channel and User2 (ADC and DAC operation clock = 2F) that supports two frequency channels and has a frequency switching circuit 205 is shown. ing.

First, it is assumed that detects the User1, User2 signal frequency channel _{F 2} is the primary frequency channel together. From the base station communication apparatus using a frequency channel _F 1 to F _3, the channel transmission request CR1~CR3 is transmitted. The terminal communication device User1 performs the same operation as in FIG.

On the other hand, the terminal communication device User2 has a frequency switching function and can receive two frequency channels using a band of 2F. In this case, the terminal communication device User2 receives channel transmission request CR1 signal in the same frequency channels and _{F 2} and the terminal communication device User1. Then, the transmission request extracting circuit 207 that transmits data by using the notification signal from the extracted channel transmission request signal CR1 which is the communication information for the own-terminal communication device, extracts frequency channel F ₃ and F ₄ have received The communication information is output to the instantaneous reference signal frequency switching circuit 205 and the notification signal transmission circuit 206.

Next, the instantaneous reference signal frequency switching circuit 205, based on the received communication device information, to receive data by using the frequency channel _{F 3} and _{F 4} to the radio unit 203-1 to _{203-M r} and specify the frequencies in the radio unit 203-1 to _{203-M r} changes the frequency of the reference signal, switch to receive data frequency channel _{F 3} and _{F 4} are output to the receiving signal decoding circuit 202. When the switching is completed, the radio unit 203-1 to _{203-M r} transmits a channel reception preparation completion notification CTS2 and CTS3 on the frequency channel _{F 3} to the base station apparatus. When the data to User2 shown in Figure 6 is transmitted from the base station communication device, terminal communication device User2 receives data using the frequency channel F ₃ and F _4. After the data reception end, the reception signal decoding circuit 202, after confirming that there is no error, outputs the normal reception information to the notification signal transmitter circuit 206, via the radio unit 203-1 to _{203-M r,} frequency channel F ₃ is used to transmit an acknowledgment ACK2 to the base station communication device. Then, after acknowledgment ACK2 transmission end, the instantaneous reference signal frequency switching circuit 205, switch back the frequency channel at time _{T 2,} the frequency channel comprising _{F 2} from _{F 3} and _{F 4.}
By controlling in this way, transmission can be performed by effectively utilizing the wide frequency band 3F of the frequency F of the clock signal of User1 + the frequency 2F of the clock signal of User2 and throughput can be improved. Here, for example, when F = 20 MHz, communication can be performed using a band of 3F = 60 MHz.

  Here, when only the confirmation of the frequency conversion operation by the frequency switching circuit 205 is notified, the channel reception preparation completion notification CTS3 may not be transmitted. Also, CTS3 is required when performing signal processing such as beam forming using channel information in the base station communication apparatus or when constructing an NAV. Further, the channel reception preparation completion notifications CTS2 to CTS3 may be transmitted as a continuous signal having no frequency blank.

Further, FIG. 3, as with the description of FIG. 4, when the operation clock 3F that terminal communication device User2 can receive frequency channel _F 2 to F ₄ simultaneously, the channel transmission request CR1 is transmitted using the frequency channel _{F 2} the channel transmission request CR2 is transmitted using the frequency channel _{F 3,} channel transmission request CR3 is may be transmitted using the frequency channel _{F 4} (surrounded by a dotted line in FIG. 6 CR2 (c61), CR3 (c62)). In this case, the terminal communication device User2 MAY be transmitted an acknowledgment ACK3 on the frequency channel _{F 4} not only acknowledgment ACK2 (acknowledgment ACK3 (c64 surrounded by a dotted line in FIG. 6)).

In the first embodiment, the example in which the terminal communication device includes the instantaneous reference signal frequency switching circuit 205 has been described. However, in the configuration illustrated in FIG. 2, the frequency of the ADC for transmission and reception, the frequency of the maximum clock signal of the DAC, and the like. The means for notifying the base station communication apparatus of the communication apparatus information is essential, but the instantaneous reference signal frequency switching circuit 205 which is a means for switching the reference signal frequency (clock signal frequency) is not essential depending on the application. For example, instead of switching the reference signal frequency, it may be switched which frequency band of the frequency channels F _{1 to} F ₄ is used for reception. Also in the case of FIG. 6, when User 2 has an operation clock of 3F or more, the frequency channels F ₃ and F ₄ can be used without the frequency switching function.

[Second Embodiment]
Next, a second embodiment of the present invention will be described.
FIG. 7 is a block diagram illustrating a configuration example of the base station communication apparatus according to the second embodiment. The base station communication device includes a data output circuit 300, a transmission signal conversion circuit 301, a notification signal insertion circuit 302, radio units 303-1 to 303-M _t , antennas 304-1 to 304-M _t , and a communication device information storage circuit 305. , A communication method determination circuit 306, a channel information estimation circuit 307, and a transmission weight calculation circuit 308.

The data output circuit 300 receives the communication device information output from the communication method determination circuit 306, and performs interleaving / modulation / modulation on the data addressed to the designated communication partner according to the modulation method / coding method based on the received communication method information. Encode and output to the transmission signal conversion circuit 301.
The transmission signal conversion circuit 301 receives the data output from the data output circuit 300 and the transmission weight information output from the transmission weight calculation circuit 308, multiplies the input data by the transmission weight, and converts the converted signal into a communication signal insertion circuit. It outputs to 302.

The notification signal insertion circuit 302 receives the converted signal output from the transmission signal conversion circuit 301 and the communication device information output from the communication method determination circuit 306. Based on the received communication device information, a predetermined signal of the converted signal is received. A transmission signal in which a signal for notifying a terminal communication apparatus as a communication partner and a transmission mode indicating a modulation scheme and a coding rate is inserted is generated at the location of, and the generated transmission signal is transmitted to radio sections 303-3 to 303. and outputs it to the -M _t.

Radio units (transmitting units and receiving units) 303-3 to 303 -M _t convert the transmission signal from the notification signal insertion circuit 302 to a frequency to be transmitted, and transmit it using the antennas 304-1 to 304 -M _t . The radio unit _{303-1~303-M t} includes ADC for receiving, and the DAC. ADC outputs a signal antenna 304-1 to _{304-M t} is receiving communication device information storage circuit 305 into a digital signal, and the channel information estimation circuit 307. DAC converts the digital signal from the notification signal insertion unit 302 into an analog signal transmitted by the antenna 304-1 to _{304-M t.} That is, the radio units 303-1 to 303-M _t and the antennas 304-1 to 304-M _t perform transmission and reception of radio signals.

The channel information estimation circuit 307 receives the reception signal output from the radio units 303-3 to 303 -M _t and decodes the received reception signal. Further, the channel information estimation circuit 307 estimates channel information between the antenna of the terminal communication device that is the communication partner communication device and the antenna of the base station communication device from the received signal received, and is obtained when decoding the channel information and the signal. The received terminal communication device information is output to the communication device information storage circuit 305. The channel information is estimated by, for example, transmitting signals known to each other in the base station communication device and the terminal communication device, and analyzing how the original known signal has changed from the received signal information. Thus, channel information can be obtained. Alternatively, the channel information used when the terminal communication device decodes the data in the downlink is fed back to the base station communication device, so that the channel information can be obtained from this information.

  The communication device information storage circuit 305 receives the channel information and terminal communication device information output from the channel information estimation circuit 306 and stores them for each terminal communication device that is a communication partner. For example, while updating the terminal information including at least one of the operation clock, the presence / absence of the multi-user MIMO mode, the presence / absence of the frequency switching function, and temporal stability, and the latest channel information of the corresponding terminal communication counterpart device Remember. When one or more terminal communication devices for communication are determined, the communication device information storage circuit 305 transmits the terminal information of the corresponding terminal communication device and / or channel information to the communication method determination circuit 306 and the transmission weight. The result is output to the calculation circuit 308.

  The communication method determination circuit 306 receives the communication device information output from the communication device information storage circuit 305, and from the received communication device information and / or channel information, assigns a frequency channel used for communication, and corresponds to the terminal communication device. The transmission mode including the number of streams to be transmitted and the modulation scheme / coding scheme is determined. Further, the communication method determination circuit 306 generates a CR to be transmitted to the terminal communication device that is a communication partner, outputs the CR to the notification signal insertion circuit 302, and determines the determined communication method information in the data output circuit 300 and the notification signal insertion circuit. It outputs to 302. Note that the communication method determination circuit 306 can select a terminal communication device to be a communication partner from the received communication device information and / or channel information, or terminal communication to be communicated from the outside. You may make it designate an apparatus.

  The transmission weight calculation circuit 308 receives the channel information output from the communication device information storage circuit 305, the communication partner and transmission mode information determined by the communication method determination circuit 306, and based on the received communication method and channel information, Calculate the transmission weight. Further, the transmission weight calculation circuit 308 evaluates the transmission characteristics according to the combination of communication partners based on the information stored in the communication device information storage circuit 305 before the communication partner is determined, and The evaluation result can be used when the communication method determination circuit 306 determines the communication partner and the transmission mode.

Next, a specific control method according to the second embodiment will be described with reference to FIGS. 8 to 11 are conceptual diagrams for explaining the control method according to the second embodiment. Note that, in FIGS. 8 to 11, as a prerequisite, the primary channel is a frequency channel F ₂ is set. The terminal communication device is the same as that shown in FIG.

  In FIG. 8, it is assumed that the base station communication apparatus has an ADC and a DAC that cover two or more frequency channels (operation clock of ADC and DAC ≧ 2F), and one frequency channel is supported as a communication partner. A communication method between the terminal communication device User1 (ADC and DAC operation clock = F) and User2 (ADC and DAC operation clock = 2F) supporting two frequency channels is shown.

  Here, these two communication partners have a multi-user MIMO mode in which multi-users are spatially multiplexed. Multi-user MIMO transmission is a technique that enables transmission to a plurality of communication partners using the same time and the same frequency by using channel information on the transmission side, such as Block diagonalization algorithm, Successive optimization algorithm, Dirty paper coding and the like are known, and any communication apparatus that performs transmission requires highly accurate channel information. The third axis labeled “Users” in the figure indicates that communication partners are multiplexed by the multiuser MIMO transmission being used.

First, the base station communication apparatus, a frequency channel _{F 2,} and transmits a channel transmission request CR1, the frequency channel _{F 3,} and transmits the channel transmission request CR2. The channel transmission request CR1, to communicate with the now User1 and User2, and User1, a frequency channel F _2, and User2, notified that transmit at a frequency channel _{F 2} and the frequency channel _{F 3} There is a signal to do. At this time, since two communication partners are assigned to the frequency channel F ₂ , it can be determined that the multi-user MIMO mode is set, and a signal for notifying that multi-user MIMO communication is performed is transmitted as a channel transmission request. It can also be included in CR1.

Radio unit 203-1 to _{203-M r} of the terminal communication device User1, like the first embodiment, receives a channel transmission request CR1 on the frequency channel _{F 2.} Next, the transmission request extraction circuit 207 extracts communication device information from the received notification signal, and outputs the extracted communication device information to the notification signal transmission circuit 206. Then, the notification signal transmitting circuit 206 outputs the communication device information to the radio unit 203-1 to _{203-M r,} based on the communication information that transmit at frequency channel _{F 2} received, the channel on the frequency channel _{F 2} a reception preparation completion notification CTS1 via at least one antenna 204-1 through _{204-M r} transmits to the base station communication apparatus.

On the other hand, the radio unit 203-1 to _{203-M r} likewise terminal communication device User2 receives channel transmission request CR1 on the frequency channel _{F 2.} Next, the transmission request extraction circuit 207 extracts communication device information from the received notification signal, and outputs the extracted communication device information to the notification signal transmission circuit 206. Then, the notification signal transmitter circuit 206, based on the communication information that outputs communication device information to the radio unit 203-1 to _{203-M r,} transmit at frequency channel _{F 2} and _{F 3} received, the frequency channel F ₃ in the channel reception preparation completion notification CTS2 via at least one antenna 204-1 through _{204-M r} transmits to the base station communication apparatus. Or, by receiving CR2, it is also possible to obtain the communication information that perform transmission even frequency channel F _3. Further, the reception preparation completion notification can be transmitted as shown in CTS 3 of FIG. 8 using the frequency channel F ₂ .

When transmitting the channel reception preparation completion notification CTS, a channel estimation pilot (CP) for channel estimation can be included in the CTS and transmitted (step of including a pilot signal). With this pilot signal CP, the base station communication apparatus can reduce the amount of time delay from channel information estimation to transmission, reduce characteristic deterioration with respect to temporal fluctuations in the propagation environment, and improve the accuracy of signal processing for multiuser MIMO. Can be improved. In addition to transmitting a CP for multi-user MIMO, the transmission side can also be used for transmission directivity control techniques such as eigenvector transmission. However, multi-user MIMO mode CTS2 in frequency channel F ₂ not subjected to can also be notified of the reception preparation completion using only CTS3 not send need not necessarily adding a pilot signal CP2, or CTS2 . When transmitting a CTS including two CP on the frequency channel overlapping as CTS1 and CTS3 in frequency channel F ₂ notifies the delay time in advance CR1 per terminal communication device, the delay time lag Can also be set to return CTS (step of including delay amount information).

Next, the wireless unit _{303-1~303-M t} of the base station communication device receives at least one of channel reception preparation completion notification CTS1～3, spatial multiplexing multiuser MIMO mode frequency channel _{F 2} transmitted to perform User1 and User2, and transmits the data to User2 the frequency channel _{F 3.}

Then, the radio unit 203-1 to _{203-M r} of the terminal communication device User1 receives data on the frequency channel _{F 2} transmission, after the data reception end, the acknowledgment ACK1 to the base station communication apparatus on the frequency channel _{F 2} To do. Furthermore, the radio unit 203-1 to _{203-M r} of the terminal communication device User2 can receive the data on the frequency channel _{F 2} and _{F 3,} after the data reception end, the base station communicates an acknowledgment ACK2 on the frequency channel _{F 3} Send to device.
When acknowledgment ACK transmission, the acknowledgment ACK1 the terminal communication device User1 on the frequency channel _{F 2,} and send an acknowledgment ACK2 of User2 on the frequency channel _{F 3,} is not the signal collision at the base station communication apparatus. For this reason, the frequency channel which does not overlap with another terminal communication apparatus can be notified to terminal communication apparatus which has a wider band using CR.
Alternatively, when an acknowledgment ACK is returned for each frequency channel, an acknowledgment ACK3 can be transmitted (ACK3 (c82) surrounded by a dotted line in FIG. 8). In this case, the ACK transmission delay time can be notified by the channel transmission request CR1 so as to shift the transmission timing, and the ACK can be transmitted by being sent by the delay time of the own terminal device. By controlling in this way, the frequency band that can be used for communication can be increased, and further, the communication speed can be increased by multiplexing communication partners with multi-user MIMO.

Also, by transmitting so that interference does not occur between the terminal communication devices User1 and User2 on the base station side, User1 and the terminal communication device can decode without understanding that the multi-user MIMO mode is performed. You can also. In this case, or put the communication information to User2 in a form unreadable to User1 in CR1, transmission information that transmitted using the CR2 in frequency channel _{F 2} and _{F 3} to User2 using frequency channel _{F 3} Can be included. The channel transmission requests CR1 and CR2 may be similar signals, or a signal may be input only to the channel transmission request CR1. The channel transmission request CR2 may be a dummy signal for obtaining a transmission prohibited section.

  Next, in FIG. 9, it is assumed that the base station communication apparatus has an ADC and a DAC that cover three or more frequency channels (operation clock of ADC and DAC ≧ 3F). Communication with terminal communication devices User1 and User3 (ADC and DAC operation clock = F) supporting channels, and User2 (ADC and DAC operation clock = 2F) supporting two frequency channels and having a frequency switching circuit 205 The method is shown.

First, the terminal communication device User1~User3 detects a signal of the frequency channel _{F 2} are both primary frequency channel. Base station transmitted channel transmission request CR1 is a frequency channel F ₂ from the communication device, transmitted channel transmission request CR2 on the frequency channel F ₃ is, channel transmission request CR3 is sent on the frequency channel F _4.
Then, the radio unit 203-1 to _{203-M r} of the terminal communication device User1 and User3 receives a channel transmission request CR1 on the frequency channel _{F 2,} the timing so as not to overlap the channel reception preparation completion notification CTS signal shifting each transmits to the base station communication apparatus on the frequency channel _{F 2} channel reception preparation completion notice CTS1 and CTS3 the by. When transmitting the channel reception preparation completion notifications CTS1 and CTS3, the transmission timing of the channel reception preparation completion notification CTS can be adjusted by specifying a delay time using the pilot signal CR.

On the other hand, the radio unit 203-1 to _{203-M r} of the terminal communication device User2 also receives channel transmission request CR1 on the frequency channel _{F 2.} Next, the transmission request extraction circuit 207 extracts that data is received by the frequency channels F ₃ and F ₄ based on the received channel transmission request CR 1, and based on the extracted result, the instantaneous reference signal frequency switching circuit 205 switching from the reference frequency _{F 2} of the radio unit 203-1 to _{203-M r} in _{F 3} and _{F 4,} it is transmitted on frequency channel _{F 3} channel reception preparation completion notification CTS2 to the base station communication apparatus.
The channel reception preparation completion notification CTS may be transmitted including a pilot signal CP for estimating channel information for performing multi-user MIMO transmission.

The channel reception preparation completion notification CTS2 (c 91) and in FIG. 9, the data signal (c92) is a long structure in the frequency direction depends on frequency channel _{F 3} and _{F 4,} a frequency band of the 2F because of the low clock User is not multiplexed in the frequency channel F ₃ and F ₄ used, is because there is no need to use a guard band on the boundary of the frequency channel F ₃ and F _4, compared with the case of FIG. 8, 2F The communication device of the communication partner using can effectively use the frequency. Therefore, the communication apparatus of the communication partner using the same frequency of the clock signal can improve the throughput as much as it is not necessary to set the guard band of the frequency when multiplexed in the same frequency band. Since the frequency channels F ₃ and F ₄ do not use the multi-user MIMO mode, the channel reception preparation completion notification CTS2 or CP2 can be not transmitted, and the User 2 in order to construct the NAV in the frequency channel F ₃ CTS2 is not decoded, but can be transmitted.

After the data reception, the terminal communication device User1 and User3, send an acknowledgment ACK1, ACK3 in frequency channel _{F 2,} the terminal communication device User2, after sending an acknowledgment ACK2 on the frequency channel _{F 3,} the frequency switching circuit 205 To change to a frequency channel including the original frequency channel F ₂ (time T ₂ ). ACK2 is can either be transmitted in the frequency channel F _4, it may be sent on the frequency channel _{F 2} after _{T 2.}

Incidentally, an example has been described where the terminal communication device User1~User3 receives a channel transmission request CR1 on the primary frequency channel _{F 2,} the channel transmission request CR2 (c 93) in the terminal communication device User2 frequency channel _{F 3} or frequency channels _{F 4} The communication information may be acquired from the channel transmission request CR3 (c94). Also, at least one of the channel transmission requests CR1 to CR3 includes communication information indicating which frequency channel each terminal communication device uses to receive data.

  Next, in FIG. 10, it is assumed that the base station communication apparatus has an ADC and a DAC that cover four frequency channels (operation clock of ADC and DAC ≧ 4F), and one frequency channel is used as a communication partner. Supported terminal communication devices User1 and User3 (ADC and DAC operation clock = F), two frequency channels are supported, User2 (ADC and DAC operation clock = 2F), and four frequency channels Shows a communication method with User4 (ADC and DAC operation clock = 4F) that support the above.

First, the terminal communication device User1~4 is in the primary frequency channel and _{F 2} together. In frequency channel _F 1 to F ₄ from the base station communication apparatus, channel transmission request CR1~CR4 is transmitted, the radio unit 203-1 to _{203-M r} of each terminal communication device, the channel transmission request on the frequency channel _{F 2} Receive CR3. After receiving channel transmission request CR3, the terminal communication device User1 is that the signal to the own communication device is a frequency channel _{F 1,} User2 is a signal to the own communication device is a frequency channel _{F 3} and _{F 4} , User3 is that the signal to the own communication device is a frequency channel _{F 2,} User4 is a signal frequency channel _F 1 to F ₄ to the own communication device, _{F 1} and _F 2, _{F 2} and _{F 3} Each transmission request extraction circuit 207 extracts that the band is between guard bands, and User 1 and User 2 that need to switch frequencies output the extracted communication device information to the reference frequency switching circuit 205. Then, at time _{T 1,} the reference frequency switching circuit 205, based on the received communication device information, switching to receive the radio unit 203-1 to _{203-M r} of the terminal communication device User1 on the frequency channel _{F 1,} switching the radio unit 203-1 to _{203-M r} of the terminal communication device User2 to receive on the frequency channel _F 3 to F _4.

Then, the radio unit 203-1 to _{203-M r} of the terminal communication device User1 sends a channel reception preparation completion notification CTS1 to the base station communication apparatus on the frequency channel _{F 1,} the radio unit of the terminal communication device User2 203-1 _{~203-M r} transmits on the frequency channel _F 3 to F ₄ channel reception preparation completion notification CTS2 to the base station communication apparatus, the radio unit 203-1 to _{203-M r} of the terminal communication device User3 the frequency channel F ₂ transmits a channel reception preparation completion notification CTS3 to the base station communication device, and the transmission signal converter 101 of the terminal communication device User4 determines where the guard band is between the four frequency channels from the information included in the channel transmission request CR. determines the set, the radio unit 203-1 to _{203-M r,} the channel reception preparation completion notification on the frequency channel _F 1 to F ₄ TS4, CTS5, using at least one of CTS 6, and transmits to the base station communication apparatus. These CTS 1 to 6 may include CPs 1 to 6 for the base station to estimate channel information. In FIG. 10, the guard band is set between the frequency channels F ₁ and F ₂ and between the frequency channels F ₂ and F ₃ . At this time, the transmission timing of the channel reception preparation completion notification CTS can be adjusted by designating a delay time by the channel transmission request CR.

The channel reception preparation completion notifications CTS2 (c101) and CTS6 (c102) in FIG. 10 and the data signals c103 and c104 have a structure that is long in the frequency direction is a frequency channel using a frequency band of 2F (= 40 MHz) This is because the low clock User is not multiplexed on F ₃ and F ₄ and the multiplexed User 4 has the clock 4F.

In FIG. 10, between the frequency channels F ₁ and F ₂ and between the frequency channels F ₂ and F ₃ , the out-of-band signal does not become an interference signal due to the clock performance of the communication devices of the terminal communication devices User 1 to User _3. Since a guard band is necessary to achieve the above, no data signal is included in this section. Terminal communication device User4 includes a frequency channel _F 1 to F _4, decodes the boundary of the data signal with the frequency channel _{F 3} and _{F 4,} transmits an acknowledgment ACK4. ACK4 may also be sent at any frequency frequency channel _F 1 to F _4.
After completion of data reception, the terminal communication device User1 sends an acknowledgment ACK1 to the base station communication apparatus on the frequency channel _{F 1,} acknowledgment ACK1 after transmission, the instantaneous reference signal frequency switching circuit 205, F frequency channels from _{F 1} Return to ₂ (time T ₂ ). Furthermore, the terminal communication device User2 sends an acknowledgment ACK2 to the base station communication apparatus on the frequency channel _{F 3,} acknowledgment ACK2 after transmission, the instantaneous reference signal frequency switching circuit 205, F the frequency channel from the _{F 3} and _{F 4 2} (time T ₂ ). Furthermore, the terminal communication device User3 transmits an acknowledgment ACK3 to the base station communication apparatus on the frequency channel _{F 2.}

Incidentally, an example has been described where the terminal communication device User1~User4 receives a channel transmission request CR2 on the primary frequency channel _{F 2,} the terminal communication device User2 receives the channel transmission request CR2 (c106) on the frequency channel _{F 3,} the terminal communication device User4 may be received channel transmission request CR4 (c 107) on the frequency channel _{F 4.} Also, at least one of the channel transmission requests CR1 to CR4 includes communication information indicating which frequency channel each terminal communication device uses to receive data.

  In the prior art, when there is even one terminal communication apparatus that does not support multi-user MIMO, the terminal communication apparatus has the lowest performance. Therefore, when a terminal communication device with low performance exists, high throughput can be realized by using a different frequency band for other high-performance terminal communication devices and terminal communication devices with low performance.

In addition, an example in which multi-user MIMO communication is performed while communicating with a terminal communication apparatus that does not support multi-user MIMO using a method of changing a frequency used for reception or decoding will be described. In the case of FIG. 9, the primary frequency channel is considered as F ₃ and will be described. Here, User2 does not have a multi-user MIMO mode and cannot share the same frequency as other terminal communication devices. In such a case, the instantaneous reference signal frequency switching circuit 205 switches the frequency channel to User1 and User3 from _{F 3} to _{F 2,} by performing advanced signal processing, such as multi-user MIMO in the frequency channel not this primary, Even if a terminal communication apparatus that does not have a multi-user MIMO mode is a partner, high throughput can be obtained. Also, in such a case, the CR2 signal uses a format that cannot be understood by User2, or the CR2 is used to notify the User1 and User2 of the frequency channel for communication and the multiuser MIMO mode, so that the User2 By simply performing communication using the conventional communication method without being conscious of the terminal communication device, the overall throughput increases.

Further, in the case of FIG. 10, by eliminating the data (c 105) to User4 in frequency channel _{F 2,} it can explain the same communication. That, User3 is not only handle a single frequency channel, frequency switching function multiuser MIMO mode is also not provided, the case can not communicate only only on the frequency channel F ₂ primary. Even in this case, the base station communication device notifies the user 1, user 2, and user 4 of the frequency channel and multi-user MIMO mode in such a way that the user can not recognize the CR 3 signal, and performs multi-user MIMO on the primary frequency channel. Thus, high throughput can be realized.

  Further, although the multi-user MIMO technique is cited as a technique for multiplexing the terminal communication apparatus, other user multiplexing techniques such as multiplexing by encoding and multiplexing by an interleaver can also be used. In this case, it is not always necessary to add a CP to the CTS signal.

  In addition, if the band to be used increases and only a part of the band is allocated to a specific terminal communication device, interference from outside the band may occur. The number of multi-values can be reduced, or the coding rate can be lowered.

  Even when the multi-user MIMO mode is included, control can be performed as shown in FIGS. 5A and 5B so that a sufficient time is provided for the time required by the instantaneous reference signal frequency switching circuit 205. In this case, the segment transmission is performed as shown in FIG. 5B, and the communication mode is changed step by step so that the communication in the format as shown in FIGS. You can also.

12 to 14 show the communication flow of the present invention. FIG. 12 is a part of a communication flow according to the first embodiment of this invention. When communication is started, the terminal communication device includes at least one of frequency information of the ADC or DAC clock signal of the terminal communication device and information indicating the presence / absence of the instantaneous switching mode of the reference signal to be down-converted Information is notified to the base station communication device (step S101). The base station communication device receives the communication device information from the terminal communication device, and the communication device information storage circuit 105 writes and stores the received communication device information (step S102).
After the terminal communication device to be the communication partner is determined, the communication method determination circuit 106 determines frequency channel assignment (step S103), and determines a transmission mode including a modulation scheme and a coding scheme (step S104). Based on the determined frequency channel assignment and transmission mode, the base station communication apparatus, the transmission signal conversion circuit 101, notification signal insertion circuit 102, the radio unit 103-1 to _{103-M t,} antennas 104-1 to _{104-M t} Then, data is transmitted to the terminal communication device. (Step S105)

FIG. 13 is a part of a communication flow according to the second embodiment of this invention. When the communication starts, the terminal communication device includes the frequency information of the ADC or DAC clock signal of the terminal communication device, the presence / absence of the instantaneous switching mode of the reference signal to be down-converted, and the information indicating the presence / absence of the multiuser MIMO mode. Communication device information including at least one is notified to the base station communication device (step S201; communication device information notification step).
Next, the channel information estimation circuit 307 of the base station communication apparatus estimates channel information with the antenna of the terminal communication apparatus using the received communication apparatus information, and calculates the estimated channel information and the received communication apparatus information. It outputs to the communication apparatus information storage circuit 305 (step S202; channel information estimation step).
Next, the communication device information storage circuit 305 receives the channel information and communication device information output from the channel information estimation circuit 307, and writes and stores the received channel information and communication device information (step S203; communication device information storage). Step), the stored channel information and communication device information are output to the communication method determination circuit 306 and the transmission weight calculation circuit 308.

After the terminal communication apparatus to be the communication partner is determined, the communication method determination circuit 306 determines the frequency channel assignment and the presence / absence / combination of spatial multiplexing by multiuser MIMO (step S204; frequency assignment / multiuser MIMO mode determination step). .
Next, the transmission weight calculation circuit 308 calculates a transmission weight using the channel information received from the communication device information storage circuit 305 (step S205; transmission weight calculation step), and communicates the calculated weight value with the transmission conversion circuit 301. It outputs to the method determination circuit 306.
Next, the communication method determination circuit 306 determines a transmission mode including a modulation scheme and a coding scheme based on the channel information and communication device information output from the communication device information storage circuit 305 (step S206).
Next, based on the determined frequency channel assignment / multi-user MIMO mode / transmission mode, the base station communication apparatus includes a transmission signal conversion circuit 301, a notification signal insertion circuit 302, radio units 303-1 to 303-M _t , an antenna, through 304-1 to _{304-M t} transmits data (step S207; transmission step).

FIG. 14 is a part of a communication flow between the terminal communication apparatus and the base station communication apparatus according to the first embodiment or the second embodiment of the present invention.
When the communication starts, the terminal communication device includes the frequency information of the ADC or DAC clock signal of the terminal communication device, the presence / absence of the instantaneous switching mode of the reference signal to be down-converted, and the information indicating the presence / absence of the multiuser MIMO mode. Communication device information including at least one is notified to the base station communication device (step S301; communication device information notification step).
The base station communication device receives the communication device information output from the terminal communication device, and the communication device information storage circuit 105 (305) writes the received communication device information and stores the channel information and the communication device information (step S401). Communication device information storage step), and the stored channel information and communication device information are output to the communication method determination circuit 106 (306).
After the terminal communication device to be the communication partner is determined, the communication method determination circuit 106 (306) uses the channel information and communication device information output from the communication device information storage circuit 105 (305) to assign frequency channels and multi-user MIMO. The presence / absence / combination of spatial multiplexing is determined (step S402; frequency channel allocation determination step), and the determined information is output to the data output circuit 100 (300) and the notification signal insertion circuit 102 (302).

Then, the base station communication apparatus, based on the assignment of the determined frequency channel, the channel transmission request signal, notifies the signal insertion circuit 102 (302), the wireless unit _103-1~103-M t (303-1~303 -M _t ) and at least one of the antennas 104-1 to 104-M _t (304-1 to 304-M _t ) (step S403; channel transmission request signal transmission step).
Next, the terminal communication device, at least one antenna 204-1 through _{204-M r,} receives a signal via at least one radio unit 203-1 to _{203-M r.} Next, the reception signal decoding circuit 202 decodes the received signal and outputs the decoded signal to the notification signal extraction circuit 201. Next, the notification signal extraction circuit 201 receives the decoded signal output from the reception signal decoding circuit 202, extracts the notification signal from the received signal, and outputs the extracted notification signal to the transmission request extraction circuit 207 (step). S302: frequency channel assignment extraction step).

Next, the transmission request extraction circuit 207 receives the notification signal output from the notification signal extraction circuit 201, and acquires the frequency channel that the base station communication apparatus transmits to the terminal communication apparatus from the received notification signal.
If they are the same as the frequency channel acquired frequency channel is used for the current received, the communication signal transmitting circuit 206, a reception preparation completion notice CTS radio section 203-1 to _{203-M r} least one and the antenna 204 transmitted via at least one _{-1~204-M r.} If the acquired frequency channel is not included in the currently decoded frequency channel, the transmission request extraction circuit 207 notifies the frequency signal information to the notification signal transmission circuit 206 and the instantaneous reference signal switching circuit 205. Next, the instantaneous reference signal switching circuit 205 receives the frequency channel information output by the transmission request extraction circuit 207, based on the frequency channel information received, changes the frequency to down-convert the radio unit 203-1 to _{203-M r} (Step S303; Frequency changing step).
Then, the notification signal transmitter circuit 206, depending on the frequency channel information output by the transmission request extracting circuit 207, at least one and antenna reception preparation completion notification CTS radio unit 203-1 to _{203-M r} 204-1 transmitted via at least one to _{204-M r} (step S304; communication preparation completion notification step).

Next, the communication method determination circuit 106 (306) of the base station communication apparatus determines a transmission mode including a modulation scheme and a coding scheme (step S404; transmission mode determination step), and outputs the determined transmission mode information as data. The data is output to the circuit 100 (300) and the notification signal insertion circuit 102 (302).
Next, after a certain time after transmitting the channel transmission request, or after receiving the CTS, the terminal communication device as the designated communication partner is notified to the notification signal insertion circuit 102 (302), the radio unit 103-1, using the designated frequency channel. At least one of the _{~103-M t (303-1~303-M} t), and transmits the data via at least one antenna _{104-1~104-M t (304-1~304-M} t) (Step S405; transmission step).

Then, receiving data via at least one of the at least one and antennas 204-1 through _{204-M r} of the wireless unit _{203-1~204-M r} of the terminal communication device (step S305).
Next, the reception signal decoding circuit 202 confirms that the data can be decoded without error, and outputs normal reception information to the notification signal transmission circuit 206 when the data can be decoded without error.
After receiving the normal reception information, the notification signal transmitter circuit 206 transmits via at least one of the at least one and antennas 204-1 through _{204-M r} of the wireless unit 203-1 to _{203-M r} the ACK ( Step S306; confirmation response signal transmission step).
Further, when switching from one frequency to be used for decoding, the reference signal frequency switching circuit 205 returns to the original frequency frequency of performing down-conversion of the radio unit 203-1 to _{203-M r} (step S307; frequency back step ).

  FIG. 11A to FIG. 11C are conceptual diagrams for explaining a method of determining a frequency channel assignment method performed by the transmission signal conversion unit 101 of the base station communication apparatus according to the second embodiment. Consider five users User1 to User5, and User1 and User2 can detect one frequency channel, User3 and User4 can detect two frequency channels, and User5 can detect four frequency channels.

In FIG. 11A, the configuration is such that users having the same clock signal frequency are grouped into the same frequency channel so as to minimize the guard band. By assigning frequency channels in this way, guard bands required at both ends of the occupied band are not required between the frequency channel F ₁ and the frequency channel F ₂ , so that the frequency can be used effectively.

FIG. 11B shows a channel arrangement that takes into account characteristic degradation due to the influence of imperfections (IQ imbalance) of the communication device. Since guard bands are required between all channels, effective use of frequencies is not always possible, but multi-users are used at frequency channels F ₁ and F ₄ at the ends of frequency channels whose characteristics deteriorate due to device imperfection. The number of communication partners performing MIMO is set smaller than the central frequency channels F ₂ and F ₃ . In this way, the number of multiuser MIMO multiplexed can be determined by considering the operating characteristics of the center frequency channel.

  In FIG. 11 (c), channels are allocated in consideration of both guard band minimization and device imperfection. By controlling in this way, device frequency is effectively utilized while device is not used. Characteristic degradation due to integrity can also be minimized.

  In the above-described embodiment, the signal sequence that has been expressed as the channel transmission request signal CR so far is transmitted as a transmission request RTS (Request to send) adopted in IEEE802.11a, IEEE802.11g, and IEEE802.11n. You can also

  In addition, a signal for designating a frequency channel used when returning an acknowledgment ACK or a channel reception preparation completion notification CTS is added to the channel transmission request CR, and the frequency channel used for the acknowledgment ACK and the channel reception preparation completion notification CTS is controlled. You can also

  Further, pilot signal CP for estimating channel information may be a known signal based on the assumption that the base station transmits Uplink channel information, or may be Downlink channel information estimated by the communication partner communication apparatus. Good or both. When a signal including both is transmitted as a pilot signal CP, the base station communication apparatus can calibrate Uplink and Downlink information.

  Further, when specifying the delay time for transmitting the channel reception preparation completion notification CTS and the acknowledgment ACK, the base station communication device specifies the delay time in the channel transmission request CR in order to increase the accuracy of the timing, When the signal is received, the base station communication device stores how much the arrival time difference has received the signal from each communication partner, so that the set amount of delay time can be optimized.

  Under the conditions in the figure, the frequency of the ADC and DAC clock signals of the base station communication device may be specified as 3F or more, but when transmitting, noise is present in the DC component that is the center of all frequency channels. Such a problem can be avoided by using 4F when a 3F clock signal frequency is required for riding. Further, the frequency of the clock signal of the base station communication device can be effectively used by using the factorial times 2 of the minimum unit (F in this case) of the communication system for all frequency bands for communication.

3 to 6 and FIGS. 8 to 10, in a user terminal communication apparatus having an ADC and a DAC having a frequency of a clock signal of 2F or more, in normal operation, the frequency channel F is switched to the frequency F clock in normal operation. _After detecting only ₂ and detecting channel reception preparation completion notification CTS and detecting that a clock of 2F or higher is necessary, the frequency of the clock signal of 2F or higher is changed to use two or more frequency channels. In addition, the power consumption of the communication device can be kept low by changing the clock to the frequency F after data reception.

  Further, when the communication device uses a plurality of frequency channels, the transmission quality of the frequency channel close to the DC component is improved due to device problems such as IQ imbalance (device imperfection). Thus, frequency channels around DC can also be used for multi-user MIMO and higher-order modulation schemes.

  In the present embodiment, the base station communication device is described as an example of the transmission side, but the base station communication device may not be fixed and may move.

  In the present invention, the frequency channel is expressed by a plurality of channels in the frequency band F. In IEEE802.11a, IEEE802.11g, and IEEE802.11n, an orthogonal wave division multiplexing (OFDM) is used in this frequency channel. Thus, it is further divided into a plurality of subcarriers. A plurality of these subcarriers can be bundled to construct a subchannel having a frequency band F or less, and the above-described technique can be used as an independent frequency channel.

In addition, a program for realizing the functions of the respective units in FIGS. 1, 2 and 7 of the embodiment is recorded on a computer-readable recording medium, and the program recorded on the recording medium is read into a computer system. The processing of each unit may be performed by executing. Here, the “computer system” includes an OS and hardware such as peripheral devices.
Further, the “computer system” includes a homepage providing environment (or display environment) if a WWW system is used.
The “computer-readable recording medium” is a portable medium such as a flexible disk, a magneto-optical disk, a ROM (Read Only Memory), a CD-ROM, or a USB (Universal Serial Bus) I / F (interface). A storage device such as a USB memory or a hard disk built in a computer system. Furthermore, the “computer-readable recording medium” dynamically holds a program for a short time like a communication line when transmitting a program via a network such as the Internet or a communication line such as a telephone line. In this case, it also includes those that hold a program for a certain period of time, such as a volatile memory inside a computer system serving as a server or client in that case. The program may be a program for realizing a part of the functions described above, and may be a program capable of realizing the functions described above in combination with a program already recorded in a computer system.

100 ... data output circuit 101 ... transmitting signal conversion circuit 102 notifies the signal insertion circuit _{103-1~103-M t, 203-1~103-M} r ··· radio unit 104-1 to _{104-M t} , 204-1 through _204-M r ... antenna 105 ... communication device information memory 106 ... communication method determining circuit 201 ... notification signal extraction circuit 202 ... reception signal decoding circuit 205 ... Instantaneous reference signal frequency switching circuit 206... Notification signal transmission circuit 207.

Claims (11)

In a communication method in which a base station communication device communicates simultaneously with a plurality of terminal communication devices including an analog-digital conversion device (ADC) or a digital-analog conversion device (DAC) of a received signal,
Each of the terminal communication devices includes communication device information including at least one of frequency information of an ADC or DAC clock signal included therein and information indicating the presence / absence of an instantaneous switching mode of a reference signal to be down-converted. A communication device information notification step for notifying the device;
The base station communication device extracts each communication device information notified from each terminal communication device, and stores each extracted communication device information.
The base station communication device allocates a frequency channel to each terminal communication device based on the frequency information of each clock signal included in each extracted communication device information and information indicating the presence / absence of each frequency switching mode. Determining a frequency channel assignment to be determined;
A transmission mode determination step in which the base station communication device determines a transmission mode consisting of a modulation scheme and a coding rate at the time of data transmission to the terminal communication device, based on the determined allocation of each frequency channel;
A transmission step in which the base station communication device converts data to be transmitted based on the determined modulation scheme, coding rate, and frequency channel assignment to the terminal communication device, and transmits data to each terminal communication device. When,
A communication method comprising: A channel information estimation step for estimating each channel information between the base station communication device and the terminal communication device based on a received signal received from each terminal communication device;
A communication device information storage step for storing the estimated channel information and communication device information for each terminal communication device;
Frequency allocation / multiuser in which the base station communication device determines a multi-user MIMO mode for performing frequency channel assignment and spatial multiplexing used for data transmission to each terminal communication device based on the extracted communication device information MIMO mode determination step;
A transmission weight calculating step in which the base station communication device calculates each transmission weight value for data transmission of each terminal communication device based on the estimated channel information;
The base station communication device converts data to be transmitted based on the determined modulation scheme, coding rate, frequency channel assignment, spatial multiplexing mode, and transmission weight value, and for each terminal communication device Sending step for sending data,
The communication method according to claim 1, further comprising: A channel transmission request signal transmission step in which the base station communication device transmits a channel transmission request signal including the determined allocation of each frequency channel to the terminal communication devices;
A frequency channel assignment extraction step for the terminal communication device to extract a frequency channel assignment for the terminal communication device from the channel transmission request signal;
If the extracted frequency channel assignment is outside the frequency channel currently receiving data, the terminal communication device changes the frequency of a reference signal used for frequency conversion based on the extracted frequency channel assignment. A frequency changing step for changing the frequency channel on which the ADC or the DAC performs conversion,
After the terminal communication device receives data on the changed frequency channel and confirms that data reception from the base station communication device is completed, the confirmation response signal is changed to the base station communication device. An acknowledgment signal transmitting step for transmitting on the frequency channel;
A frequency returning step in which the terminal communication device returns to the frequency channel before changing the frequency channel after transmitting the acknowledgment signal, or returns to the frequency before changing the frequency of the clock signal;
The communication method according to claim 1, further comprising: The terminal communication device is ready for communication to transmit to the base station communication device a communication preparation completion notification signal for notifying that preparation for data reception is completed after the frequency channel assignment extraction step or the frequency change step. Notification step,
The communication method according to claim 3, further comprising: A pilot signal that specifies which frequency channel is used to transmit the acknowledgment signal to a transmission request signal for notifying the terminal communication device of the determined frequency channel assignment to the base station communication device. Including steps,
The communication method according to claim 3, further comprising: When the base station communication device multiplexes data of the plurality of terminal communication devices on the determined one frequency channel, a transmission request signal for notifying the terminal communication device of the determined frequency channel, Including delay amount information for designating an individual delay time calculated by the transmission weight calculation unit for the terminal communication device when transmitting the confirmation response signal or the communication preparation completion notification signal;
The communication method according to claim 3 or 4, further comprising: When the frequency channel allocation determining step of the base station communication device multiplexes data of a plurality of the terminal communication devices on the determined one frequency channel, the guard band region set between the frequency channels is reduced. 3. The communication method according to claim 2, wherein the terminal communication devices having ADCs or DACs having the same clock signal frequency are controlled to be multiplexed on the same frequency channel. In the frequency channel allocation determining step, at least one terminal communication device among the plurality of terminal communication devices that perform transmission has information regarding a method of multiplexing data destined for the plurality of terminal communication devices on the same frequency channel at the same time The frequency channel is allocated so that the data is multiplexed simultaneously on the same frequency channel by another terminal communication device other than the frequency channel supported by the terminal communication device when there is not. The communication method described. In a communication system in which a base station communication device simultaneously communicates with a plurality of terminal communication devices including an analog-digital conversion device (ADC) or a digital-analog conversion device (DAC) of a received signal,
The terminal communication device is
A notification signal for notifying the base station communication device of communication device information including at least one of frequency information of the ADC or DAC clock signal included therein and information indicating the presence / absence of the instantaneous switching mode of the reference signal to be down-converted Transmission circuit,
With
The base station communication device
Extracting each communication device information notified from each terminal communication device, and storing each extracted communication device information;
Based on the frequency information of each clock signal included in each stored communication device information and information indicating the presence / absence of each frequency switching mode, allocation of each frequency channel at the time of data transmission to each terminal communication device is determined. A communication method determining circuit for determining a transmission mode composed of a modulation scheme and a coding rate at the time of data transmission to the terminal communication device based on the determined allocation of each frequency channel;
A transmission signal conversion circuit for converting data to be transmitted based on the determined modulation scheme, coding rate, and frequency channel assignment for the terminal communication device;
A radio unit for converting the converted transmission signal into a transmission frequency;
An antenna to transmit,
A communication system comprising: In a base station communication device that communicates simultaneously with a plurality of terminal communication devices including an analog-digital conversion device (ADC) or a digital-analog conversion device (DAC) of a received signal,
A channel information estimation circuit for estimating channel information from a signal transmitted from each terminal communication device;
A communication device information storage circuit for storing each communication device information and the channel information notified from each terminal communication device;
Based on the frequency information of each clock signal included in each stored communication device information and information indicating presence / absence of each frequency switching mode, or channel information, or both, at the time of data transmission to each terminal communication device Determine the assignment of each frequency channel,
A communication method determining circuit for determining a transmission mode including a modulation scheme and a coding rate at the time of data transmission to the terminal communication device based on the determined allocation of each frequency channel;
A transmission signal conversion circuit for converting data to be transmitted based on the determined modulation scheme, coding rate, and frequency channel assignment for the terminal communication device;
A radio unit for converting the converted transmission signal into a transmission frequency;
An antenna to transmit,
A base station communication device comprising: In a terminal communication device that communicates with a base station communication device and includes an analog-digital conversion device (ADC) or a digital-analog conversion device (DAC) of a received signal,
A transmission request extraction circuit for acquiring a specified frequency channel from the base station communication device;
An instantaneous reference signal frequency switching circuit for switching a frequency to receive a specified frequency channel;
A terminal communication apparatus comprising:

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