JP2014017617A - Radio communication method, radio communication system, upper-level device, and computer program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radio communication method that makes it possible to shorten a transmission delay time in radio communication.SOLUTION: An access point acquires transmission right in a communication channel, and performs both of downlink radio communication from its own device to a terminal and uplink radio communication from the terminal to the own device at one transmission opportunity from acquisition of transmission right to release of the transmission right. Because both uplink communication and downlink communication are performed at one transmission opportunity, and there is no need to acquire transmission right again, a transmission delay time can be shortened and throughput can be improved due to increase in frequency resources available for communication.

Description

  The present invention relates to wireless communication technology.

  As a medium access control method in a wireless network, it is not a method of granting a transmission opportunity to an access point (AP) or terminal, but the access point or terminal autonomously acquires a transmission right and transmits the transmission right after data transmission. A release method has been proposed (see, for example, Non-Patent Document 1). In this method, single user communication between an access point and a single terminal is performed in one transmission opportunity. An access point (or base station BS (Base Station)) or a single terminal occupies the acquired frequency resource and uses it for transmission. As a result, the transmission delay time increases. Also, sufficiently high frequency utilization efficiency cannot be obtained, leading to a decrease in throughput.

  As a countermeasure, a method of performing multi-user communication between an access point and a plurality of terminals in one transmission opportunity by introducing a multiple access method has been proposed (for example, Non-Patent Documents 2 and 3). Compared to single-user communication, in multi-user communication, uplink multi-user communication or downlink multi-user communication is performed between an access point and a plurality of terminals in one transmission opportunity. Therefore, transmission can be started earlier, and transmission delay time is reduced. Further, the throughput is also improved by improving frequency resource utilization efficiency (in the case of Spatial Division Multiple Access (SDMA), channel capacity expansion, and in the case of Orthogonal Frequency Division Multiple Access (OFDMA), multi-user diversity effect).

IEEE 802.11-2007, IEEE Standard for Information technology-Telecommunications and information exchange between systems-Local and metropolitan area networks-Specific requirements-Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications Daewon Jung, Hyuk Lim, “Opportunistic MAC Protocol for Coordinating Simultaneous Transmissions in Multi-User MIMO Based WLANs,” IEEE Communications Letters, Vol. 15, No. 8, pp. 902-904, Aug. 2011. Stefan Valentin, Thomas Freitag, Holger Karl, “Integrating Multiuser Dynamic OFDMA into IEEE 802.11 WLANs-LLC / MAC Extensions and System Performance,” Proc. Of 2008 IEEE International Conference on Communications (ICC'08), pp. 3328-3334, May 2008.

  However, only one of the downlink multiuser communication and the uplink multiuser communication is performed in one transmission opportunity. Therefore, in order to start uplink multi-user communication after the end of downlink multi-user communication, it is necessary to acquire the transmission right again. The same applies when downlink multiuser communication is started after the completion of uplink multiuser communication.

  In a medium access control method that autonomously acquires a transmission right, such as CSMA / CA (Carrier Sense Multiple Access with Collision Avoidance), a transmission right is generally acquired. In addition, a period of time during which the frequency resource is unused (idle) occurs for a long period of time. For this reason, in multi-user communication in which it is necessary to reacquire the transmission right every time switching between uplink and downlink, there is a problem that transmission delay time becomes long and throughput is reduced.

  In view of the above circumstances, an object of the present invention is to provide a technique capable of reducing the transmission delay time in wireless communication.

  One aspect of the present invention is a wireless communication method performed by a terminal and a host device thereof, wherein the host device acquires a transmission right in a communication channel and releases the transmission right; In a single transmission opportunity from acquiring the transmission right until releasing the transmission right, both downlink wireless communication from the own device to the terminal and uplink wireless communication from the terminal to the own device are performed. The upper apparatus side communication step to be executed, and the terminal performs both the downlink radio communication from the upper apparatus to the own apparatus and the uplink radio communication from the own apparatus to the upper apparatus at the one transmission opportunity. And a terminal side communication step to be executed.

  One aspect of the present invention is the above-described wireless communication method, wherein in the upper device side communication step, the upper device performs one or both of downlink wireless communication and upstream wireless communication a plurality of times at the one transmission opportunity. And performing pre-processing and post-processing related to the downlink radio communication or the uplink radio communication before and after the main process, respectively, and in the terminal-side communication step, the terminal performs the one transmission opportunity. One or both of the downlink radio communication and the uplink radio communication are performed a plurality of times, and the pre-processing and post-processing related to the downlink radio communication or the uplink radio communication are respectively performed before and after this process.

  One aspect of the present invention is the above-described wireless communication method, wherein in the upper device side communication step, the upper device performs one or both of downlink wireless communication and upstream wireless communication a plurality of times at the one transmission opportunity. Performing all pre-processing related to the downlink wireless communication or the uplink wireless communication before performing the first main processing, and performing all post-processing related to the downlink wireless communication or the uplink wireless communication in the final main processing. Implemented later, in the terminal side communication step, the terminal performs one or both of downlink radio communication and uplink radio communication a plurality of times in the one transmission opportunity, and performs all of the downlink radio communication or the uplink radio communication. Pre-processing is performed before the first main processing, and all post-processing related to the downlink radio communication or the uplink radio communication is performed after the last main processing.

  One aspect of the present invention is the above-described radio communication method, wherein in the uplink radio communication, a total value of uplink periods, a total value of the number of uplink terminals required for radio communication in the one transmission opportunity, an uplink, An upper limit is provided for any one or more of the total amount of data, and in the downlink wireless communication, the total value of the downlink period required for wireless communication in the one transmission opportunity, the number of downlink terminals An upper limit is provided for one or more of the total value and the total value of the downlink data amount.

  One aspect of the present invention is a wireless communication system including a terminal and a host device thereof, wherein the host device acquires a transmission right in a communication channel and releases the transmission right; and the transmission right Both the downlink wireless communication from the own device to the terminal and the uplink wireless communication from the terminal to the own device are executed at one transmission opportunity from the acquisition of the transmission right until the transmission right is released A higher-level device side communication unit, and the terminal performs both the downlink wireless communication from the higher-level device to the own device and the upstream wireless communication from the own device to the higher-level device at the one transmission opportunity. And a terminal-side communication unit that executes

  One aspect of the present invention includes a transmission right control unit that acquires a transmission right in a communication channel and releases the transmission right, and a transmission opportunity that occurs after the transmission right is acquired and until the transmission right is released. The host device includes a higher-level device side communication unit that performs both downlink wireless communication from the own device to the terminal and uplink wireless communication from the terminal to the own device.

  One aspect of the present invention is a transmission right control step for acquiring a transmission right in a communication channel and releasing the transmission right, and a transmission opportunity once from the acquisition of the transmission right to the release of the transmission right. A computer program for causing a computer to execute a higher-level apparatus side communication step for executing both downlink wireless communication from the own apparatus to the terminal and uplink wireless communication from the terminal to the own apparatus.

  According to the present invention, it is possible to reduce the transmission delay time in wireless communication.

1 is a block diagram showing a configuration of a wireless communication system 1 according to a first embodiment. It is a block diagram which shows the function structure of the access point AP and terminal 10 by 1st Embodiment. 4 is a flowchart for explaining the operation of the wireless communication system 1 according to the first embodiment. It is a conceptual diagram which shows the communication protocol which implements both the downlink multiuser communication and uplink multiuser communication in the radio | wireless communications system 1 by 1st Embodiment. 6 is a flowchart for explaining the operation of the wireless communication system 1 according to the second embodiment. It is a conceptual diagram which shows the communication protocol which implements both downlink multiuser communication and uplink multiuser communication by 2nd Embodiment. It is a conceptual diagram which shows the communication protocol (MAC protocol) which implements downlink multiuser communication by a prior art. It is a conceptual diagram which shows the communication protocol which implements uplink multiuser communication by a prior art. It is a conceptual diagram which shows the relationship between offered load (traffic amount of each terminal) and 90% delay time in this invention and a prior art. FIG. 6 is a conceptual diagram showing a relationship between offered load (traffic amount of each terminal) and throughput in the present invention and the 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 of a wireless communication system 1 according to the first embodiment. In FIG. 1, a wireless communication system 1 includes a plurality of terminals 10-1 to 10-n (n is an integer of 2 or more) and an access point AP that is a higher-level device. Note that the wireless communication system 1 may include another device such as a base station instead of the access point AP as a higher-level device. A plurality of terminals 10-1 to 10-n are collectively referred to as terminal 10. In the wireless communication system 1, a plurality of terminals 10-1 to 10-n (or one of the terminals 10-i: hereinafter referred to as a single terminal 10-i) and the access point AP use the acquired frequency resources. Wireless communication.

FIG. 2 is a block diagram showing functional configurations of the access point AP and the terminal 10 according to the first embodiment.
The access point AP includes a restriction setting unit 1, a transmission right control unit 2, a downlink multi (single) user communication unit 3, and an uplink multi (single) user communication unit 4. The names of the downlink multi (single) user communication unit 3 and the uplink multi (single) user communication unit 4 indicate that multi-user communication or single-user communication may be used. Hereinafter, an embodiment in which the two functional units are functional units performing multi-user communication will be described. The restriction setting unit 1 can perform a total downlink period (total period), a total uplink period (total period), and a total downlink for downlink multiuser communication and uplink multiuser communication depending on the actual communication network conditions. Maximum number of link terminals (total number of terminals), total number of uplink terminals (total number of terminals), total downlink data packet size (combined data packet size), and total uplink data packet size (combined data packet size) Set. Details of the restriction contents will be described later. The limit setting unit 1 may set an upper limit for all of the above values, or may set an upper limit for a part of the above values.

  The transmission right control unit 2 acquires the k-th transmission right (access right) and notifies the terminal 10 related to the downlink multi-user transmission of the acquired result. The transmission right control unit 2 releases the transmission right after finishing all the downlink multi-user communication and the uplink multi-user communication. The downlink multi (single) user communication unit 3 performs multiple times of downlink multi (single) user communication for transmitting information to a plurality of terminals. The uplink multi (single) user communication unit 4 performs uplink multi (single) user communication a plurality of times to receive information from a plurality of terminals. The downlink multi (single) user communication unit 3 and the uplink multi (single) user communication unit 4 are collectively referred to as a higher-level device side communication unit 5.

  The terminal 10 includes a transmission right control unit 11, an uplink communication unit 12, and a downlink communication unit 13. The transmission right control unit 11 acquires the k-th transmission right (access right) according to the notification received from the access point AP. The transmission right control unit 11 releases the transmission right after finishing all the downlink multi-user communication and the uplink multi-user communication. The uplink communication unit 12 performs uplink communication a plurality of times for transmitting information to the access point AP. The downlink communication unit 13 performs downlink multiuser communication a plurality of times for receiving information from the access point AP. The uplink communication unit 12 and the downlink communication unit 13 are collectively referred to as a terminal side communication unit 14.

  FIG. 3 is a flowchart for explaining the operation of the wireless communication system 1 according to the first embodiment. FIG. 4 is a conceptual diagram showing a communication protocol for performing both downlink multi-user communication and uplink multi-user communication in the wireless communication system 1 according to the first embodiment.

  First, in the access point AP, the restriction setting unit 1 determines the total period, the total number of terminals, the combined data for the downlink multiuser communication and the uplink multiuser communication described above according to the actual communication network status. An upper limit of the packet size is set (step S1).

Hereinafter, various upper limits set by the limit setting unit 1 will be described.
The limit setting unit 1 sets an upper limit of the total downlink period necessary for performing N downlink multiuser communications. Similarly, the limit setting unit 1 sets an upper limit of the total uplink period necessary for performing M uplink multiuser communications. For example, when the upper limit of the total downlink period is set to “0”, only uplink multiuser communication is performed. Similarly, when the upper limit of the total uplink period is set to “0”, only downlink multiuser communication is performed.

  The restriction setting unit 1 sets an upper limit of the total number of downlink terminals included in the implementation of N downlink multiuser communications. Similarly, the restriction setting unit 1 sets an upper limit of the total number of uplink terminals included in the implementation of M uplink multiuser communications. For example, when the upper limit of the total number of downlink terminals is set to “0”, only uplink multiuser communication is performed. Similarly, when the upper limit of the total number of uplink terminals is set to “0”, only downlink multiuser communication is performed.

  Further, the limit setting unit 1 sets an upper limit of the total downlink data packet size included in the implementation of N downlink multiuser communications. Similarly, the limit setting unit 1 sets an upper limit of the total uplink data packet size included in the implementation of M downlink multiuser communications. For example, when the upper limit of the total downlink data packet size is set to “0”, only uplink multiuser communication is performed. Similarly, when the upper limit of the total uplink data packet size is set to “0”, only downlink multiuser communication is performed in the first embodiment.

  As described above, by setting the upper limit of the total downlink period, the upper limit of the total uplink period, the total number of downlink terminals, the total number of uplink terminals, the total downlink data packet size, the total uplink data packet size, It can be limited to the implementation of only downlink communication or uplink communication.

  Returning to the description of FIG. After the processing of step S1, the transmission right control unit 2 of the access point AP acquires an arbitrary k-th transmission right (access right). The transmission right control unit 2 expands or improves the acquired result to realize a control signal (for example, an RTS (Request to Send) signal used in a wireless local area network (LAN)) or multi-user communication. The terminal 10 related to the downlink multi-user transmission is notified (step S2). The transmission right control unit 11 of the terminal 10 recognizes acquisition of an arbitrary k-th transmission right (access right) according to the notification received from the access point AP.

  Next, the downlink multi (single) user communication unit 3 of the access point AP and the uplink communication unit 12 of the terminal 10 perform downlink multi-user communication a plurality of times (step S3). Next, the uplink multi (single) user communication unit 4 of the access point AP and the downlink communication unit 13 of the terminal 10 perform uplink multi-user communication a plurality of times (step S4).

  FIG. 4 shows that downlink multiuser communication is performed N times and uplink multiuser communication is performed M times so as not to lose generality. However, N downlink multiuser communications and M uplink multiuser communications do not necessarily have to be performed in the order shown in FIG. Depending on the situation of the communication network, the order of downlink communication and uplink communication may be changed, and a plurality of downlink communications and a plurality of uplink communications may be performed as a group rather than as a group. .

  In addition, depending on the situation of the communication network, a de facto single-user communication including only one user terminal is performed in N downlink multiuser communication and M uplink multiuser communication to be performed. Also good.

As shown in FIG. 4, the implementation of each downlink multi-user communication is further broken down into three stages: pre-processing, main processing, and post-processing.
In the preprocessing, a control signal (for example, a CTS (Clear to Send, reception ready) signal used in a wireless LAN) or an expanded or improved CTS for realizing multi-user communication from the terminal 10 to the access point AP. Ready to start downlink multi-user transmission.

  In this process, an information signal (for example, corresponding to a data packet in the case of a wireless LAN) is transmitted from the access point AP to a plurality of terminals 10.

  In the post-processing, a control signal (for example, an ACK (Acknowledgment) signal used in a wireless LAN) or an ACK signal extended or improved to realize multi-user communication from the plurality of terminals 10 to the access point AP. Etc.) to notify the success or failure of the downlink multi-user transmission.

  Similarly, as shown in FIG. 4, the implementation of each uplink multi-user communication is further broken down into three stages: pre-processing, main processing, and post-processing.

  In the preprocessing, the access point AP transmits a control signal (for example, a CTS signal used in a wireless LAN or an extended or improved CTS signal for realizing multi-user communication) to the terminal 10, and Prepare to start link multi-user transmission.

  In this process, an information signal (for example, corresponding to a data packet in the case of a wireless LAN) is transmitted from a plurality of terminals 10 to the access point AP.

  In the post-processing, a control signal (for example, an ACK signal used in a wireless LAN or an ACK signal extended or improved for realizing multi-user communication) is transmitted from the access point AP to the plurality of terminals 10. Informing the success or failure of the uplink multi-user transmission.

  Finally, when all the downlink multi-user communication and uplink multi-user communication are finished, the transmission right control unit 2 of the access point AP and the transmission right control unit 11 of the terminal 10 transmit the current transmission right (see FIG. 4, the k-th communication right) is released (step S5).

  The multiple access method used for the downlink multiuser communication and the uplink multiuser communication described above is the multicarrier multiple access method OFDMA, the multi-antenna multiple access method SDMA, or the interleaver multiple access method IDMA (Interleaved Division Multiple Multiplexing). Access) or a combination of these multiple access schemes and multiplex transmission schemes, for example, SDM-OFDMA, OFDM-SDMA, OFDM-IDMA, and the like.

[Second Embodiment]
Next, a second embodiment of the present invention will be described.
The configuration of the wireless communication system is the same as in FIG. 1, and the configuration of the access point AP and the configuration of the terminal 10 are also the same as those in FIG.

  FIG. 5 is a flowchart for explaining the operation of the wireless communication system 1 according to the second embodiment. FIG. 6 is a conceptual diagram showing a communication protocol for performing both downlink multi-user communication and uplink multi-user communication according to the second embodiment.

  First, in the access point AP, the restriction setting unit 1 determines the total period, the total number of terminals, the combined data for the downlink multiuser communication and the uplink multiuser communication described above according to the actual communication network status. An upper limit of the packet size is set (step S10).

  Also in the second embodiment, similarly to the first embodiment, the limit setting unit 1 sets an upper limit of the total downlink period necessary for performing all N times of downlink multiuser communication. Similarly, the upper limit of the total uplink period required for implementation of all M downlink multiuser communications is set. For example, if the upper limit of the total downlink period is set to “0”, only the uplink multiuser communication is performed in the second embodiment. Similarly, if the upper limit of the total uplink period is set to “0”, in the second embodiment, only downlink multiuser communication is performed.

  Further, the restriction setting unit 1 sets an upper limit of the total number of downlink terminals included in the implementation of all N times of downlink multiuser communication. Similarly, the upper limit of the total number of uplink terminals included in the implementation of all M downlink multiuser communications is set. For example, if the upper limit of the total number of downlink terminals is set to “0”, in the second embodiment, only uplink multiuser communication is performed. Similarly, if the upper limit of the total number of uplink terminals is set to “0”, in the second embodiment, only downlink multiuser communication is performed.

  Furthermore, the restriction setting unit 1 sets an upper limit of the total downlink data packet size included in the implementation of all N downlink multiuser communications. Similarly, the upper limit of the total uplink data packet size included in the implementation of all M downlink multiuser communications is set. For example, if the upper limit of the total downlink data packet size is set to “0”, in the second embodiment, only uplink multiuser communication is performed. Similarly, if the upper limit of the total uplink data packet size is set to “0”, in the second embodiment, only downlink multiuser communication is performed.

  As described above, the total downlink period and / or the upper limit of the total uplink period, the total number of downlink terminals, and / or the total number of uplink terminals, the total downlink data packet size, and / or the total uplink data packet By setting the upper limit of the size, the second embodiment can be limited to implementation of downlink communication or uplink communication only.

  Next, in the access point AP, the transmission right control unit 2 acquires an arbitrary k-th transmission right (access right), and the acquired result is a control signal (for example, an RTS signal used in a wireless LAN or a multiuser A terminal related to downlink multi-user transmission is notified using an RTS signal extended or improved to realize communication (step S11). The terminal 10 recognizes acquisition of an arbitrary k-th transmission right (access right) according to the notification from the access point AP.

  Next, in the downlink multi (single) user communication unit 3 and the uplink multi (single) user communication unit 4 of the access point AP, and the uplink communication unit 12 and the downlink communication unit 13 of the terminal 10, All N times of downlink preprocessing and all M times of uplink preprocessing are performed (step S12). Specifically, as shown in FIG. 6, it is necessary for all N times of downlink multi-user communication and all N times of downlink pre-processing, and for all M times of uplink multi-user communication. , All M times uplink pre-processing is performed before all N times downlink multi-user communication main processing and all M times uplink multi-user communication main processing.

  In all N times downlink pre-processing and all M times uplink pre-processing, a control signal (for example, a CTS signal used in a wireless LAN or multi-user communication is realized between the access point AP and the terminal 10. By transmitting and receiving an extended or improved CTS signal, etc., preparations for starting all N times downlink (multiuser communication) main processing and all M times uplink (multiuser communication) main processing are prepared.

  Next, the downlink multi-user communication unit 3 of the access point AP and the downlink communication unit 13 of the terminal 10 perform downlink multi-user communication a plurality of times (step S13). Next, the uplink multi-user communication unit 4 of the access point AP and the uplink communication unit 12 of the terminal 10 perform uplink multi-user communication a plurality of times (step S14).

  In all N times downlink (multiuser communication) main processing and all M times uplink (multiuser communication) main processing, an information signal (for example, in the case of a wireless LAN, a data packet) between the access point AP and the terminal 10 Equivalent to).

  FIG. 6 shows that downlink multiuser communication is performed N times and uplink multiuser communication is performed M times so as not to lose generality. However, N downlink multiuser communications and M uplink multiuser communications are not necessarily performed in the order shown in FIG. Depending on the situation of the communication network, the order of downlink communication and uplink communication may be changed, or a plurality of downlink communications and a plurality of uplink communications may be disassembled without being fixed.

  In addition, depending on the situation of the communication network, the actual single user communication including only one user terminal is possible in N downlink multiuser communication and M uplink multiuser communication to be performed. .

  Next, in the downlink multi (single) user communication unit 3 and the uplink multi (single) user communication unit 4 of the access point AP, and the uplink communication unit 12 and the downlink communication unit 13 of the terminal 10, All N downlink post-processing and all M uplink post-processing are performed (step S15). Specifically, as shown in FIG. 6, all N downlink multi-user communication is performed after all N times downlink (multi-user communication) main processing and all M times uplink (multi-user communication) main processing. All N times of downlink post-processing and all M times of uplink post-processing necessary for carrying out all of the uplink multi-user communications.

  In all N times downlink (multi-user communication) post-processing and all M times uplink (multi-user communication) post-processing, the access point AP and the terminal 10 control signals (for example, an ACK signal used in a wireless LAN, or By transmitting / receiving an ACK signal extended or improved to realize multi-user communication), all N times downlink (multi-user communication) main processing and all M times uplink (multi-user communication) main processing Inform success or failure.

  Finally, when all the downlink multi-user communication and uplink multi-user communication are finished, the transmission right control unit 2 of the access point AP and the transmission right control unit 11 of the terminal 10 transmit the current transmission right (see FIG. 6, the k-th communication right) is released (step S16).

  The multiple access scheme used for the downlink multiuser communication and the uplink multiuser communication described above is the same as the first embodiment described above, the multicarrier multiple access scheme OFDMA, the multi-antenna multiple access scheme SDMA, or the interfacing scheme. -Lever multiple access schemes IDMA (Interleaved Division Multiple Access), or a combination of these multiple access schemes and multiple transmission schemes, for example, SDM-OFDMA, OFDM-SDMA, OFDM-IDMA, etc. are conceivable.

[Results of Numerical Experiments of Invention]
Next, in order to show the quantitative effect of the present invention, a numerical experiment example (simulation evaluation result) of the first embodiment (FIG. 4) described above will be described. In the first embodiment, downlink communication and uplink communication are performed once, downlink is performed first, and uplink is performed later.

  FIG. 7 is a conceptual diagram showing a communication protocol (MAC protocol) for implementing downlink multi-user communication according to the prior art. FIG. 8 is a conceptual diagram showing a communication protocol for performing uplink multi-user communication according to the prior art. In the conventional multi-user communication to be compared with the present invention, either downlink multi-user communication or uplink multi-user communication is performed in one transmission opportunity, as shown in FIG. 7 and FIG. To do.

  Note that parameters conforming to IEEE802.11g, which is a wireless LAN standard, are applied to both the present invention and the prior art. As a medium access method for acquiring a transmission right, the CSMA / CA method adopted in the IEEE 802.11 standard is used. An orthogonal frequency multiple access OFDMA scheme is used as a multiple access scheme for realizing downlink multiuser communication and uplink multiuser communication. Multi-user communication capable of multiple access of up to 4 users at a time using 13 subcarriers 15 OFDMA symbols as one basic unit was performed. Of course, since the effectiveness of the present invention is not limited to OFDMA, the same effect can be obtained by applying space division multiple access SDMA or interleave division multiple access IDMA.

  FIG. 9 is a conceptual diagram showing a relationship between offered load (traffic amount of each terminal) and 90% delay time in the present invention and the prior art. FIG. 10 is a conceptual diagram showing the relationship between offered load (traffic amount of each terminal) and throughput in the present invention and the prior art. In FIG. 9, 99% delay time represents the time at which 99% of packets generated at the access point AP and each terminal arrive at the destination (access point AP or terminal). From FIG. 9, it can be seen that the delay time is lower in the present invention than in the prior art, and the delay time can be reduced by the present invention. Further, FIG. 10 shows that the present invention has a higher throughput than the prior art, and the present invention can improve the throughput.

According to the first and second embodiments described above, the following effects can be obtained.
In downlink communication or uplink communication according to the conventional technology, only downlink communication or uplink communication is performed in one transmission opportunity. For this reason, it is necessary to acquire the transmission right again in order to start the communication of the other link after the communication of either the downlink or the uplink is completed.

  On the other hand, according to the first and second embodiments described above, both uplink communication and downlink communication are performed in one transmission opportunity, so there is no need to reacquire the transmission right. Therefore, the transmission delay time can be shortened.

  Also, according to the first and second embodiments, as described above, since the frequency of transmission right acquisition is reduced, the frequency of transmission right acquisition frequency resources is reduced (idle). By increasing the frequency resources that can be used for communication, the throughput can be improved.

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and includes designs and the like that do not depart from the gist of the present invention.

  AP ... access point, 1 ... restriction setting unit, 2 ... transmission right control unit, 3 ... downlink multi (single) user communication unit, 4 ... uplink multi (single) user communication unit, 5 ... host device side communication unit, DESCRIPTION OF SYMBOLS 10, 10-1-10-n ... Terminal, 11 ... Transmission right control part, 12 ... Uplink communication part, 13 ... Downlink communication part, 14 ... Terminal side communication part

Claims (7)

A wireless communication method performed by a terminal and its host device,
The host device acquires a transmission right in a communication channel and releases the transmission right;
In a single transmission opportunity from when the higher-level device acquires the transmission right until the transmission right is released, downlink wireless communication from the own device to the terminal, and uplink wireless from the terminal to the own device A host device side communication step for performing both communication and
A terminal-side communication step in which the terminal performs both downlink radio communication from the host device to the host device and uplink radio communication from the host device to the host device at the one transmission opportunity;
A wireless communication method. In the upper apparatus side communication step, the upper apparatus performs one or both of downlink radio communication and uplink radio communication a plurality of times in the one transmission opportunity, and performs pre-processing and post-processing related to the downlink radio communication or the uplink radio communication. The process is performed before and after each process.
In the terminal side communication step, the terminal performs one or both of downlink radio communication and uplink radio communication a plurality of times at the one transmission opportunity, and performs pre-processing and post-processing related to the downlink radio communication or the uplink radio communication. The wireless communication method according to claim 1, wherein the wireless communication method is performed before and after each processing. In the upper apparatus side communication step, the upper apparatus performs one or both of the downlink radio communication and the uplink radio communication a plurality of times in the one transmission opportunity, and performs all preprocessing relating to the downlink radio communication or the uplink radio communication. Is performed before the first main process, and all post-processing related to the downlink radio communication or the uplink radio communication is performed after the last main process,
In the terminal side communication step, the terminal performs one or both of downlink radio communication and uplink radio communication a plurality of times in the one transmission opportunity, and performs all pre-processing related to the downlink radio communication or the uplink radio communication, Performed before the first main process, and performs all post-processing related to the downlink radio communication or the uplink radio communication after the final main process.
The wireless communication method according to claim 1. In the uplink wireless communication, there is an upper limit on one or more of the total value of the uplink period, the total value of the number of uplink terminals, and the total value of the uplink data amount required for the wireless communication in the one transmission opportunity. Provided,
In the downlink radio communication, there is an upper limit on any one or more of the total value of the downlink period, the total value of the number of downlink terminals, and the total value of the downlink data amount required for the radio communication in the one transmission opportunity. The wireless communication method according to claim 1, wherein the wireless communication method is provided. A wireless communication system comprising a terminal and a host device thereof,
The host device is
A transmission right control unit for acquiring the transmission right in the communication channel and releasing the transmission right;
Both the downlink radio communication from the own device to the terminal and the uplink radio communication from the terminal to the own device at one transmission opportunity from the acquisition of the transmission right to the release of the transmission right A higher-level device side communication unit that executes
The terminal
A terminal-side communication unit that performs both downlink radio communication from the host device to the host device and uplink radio communication from the host device to the host device in the one transmission opportunity;
A wireless communication system comprising: A transmission right control unit for acquiring the transmission right in the communication channel and releasing the transmission right;
After acquiring the transmission right, one transmission opportunity from the time when the transmission right is released, both downlink wireless communication from the own device to the terminal and uplink wireless communication from the terminal to the own device. A host device side communication unit to be executed;
A host device comprising: A transmission right control step of acquiring the transmission right in the communication channel and releasing the transmission right;
After acquiring the transmission right, one transmission opportunity from the time when the transmission right is released, both downlink wireless communication from the own device to the terminal and uplink wireless communication from the terminal to the own device. A host device side communication step to be executed;
A computer program for causing a computer to execute.

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