JP6051658B2 - Wireless communication apparatus, wireless communication method and program - Google Patents

Description

The present invention, in a wireless communication network, the video information, the wireless communication device that wirelessly communicates equal information isochronous maintenance is required, such as audio information, radio communications method, and a program.

  In recent years, many wired networks have been replaced by wireless communication networks, and wireless communication technology is expected to increase in demand in the future. Wireless communication speed is dramatically improved, and it becomes possible to wirelessly communicate high-capacity video data, audio data, and other real-time communication traffic, and connect home electronic devices via a wireless communication network. Increasingly, home wireless communication networks are being built, and multiple notebook PCs (Personal Computers) and projectors are communicating wirelessly in company meeting rooms.

  When communicating video information, it is required to communicate large amounts of data at high speed and to maintain isochronism, so QoS (Quality of Service) technology for preferentially securing the communication bandwidth is required. It is necessary not to be obstructed by other communications such as use.

  Generally, in a wireless communication network composed of a plurality of wireless communication devices, each wireless communication device transmits a beacon frame at a certain period so that the wireless communication devices can communicate synchronously. In a distributed control type wireless communication network, all information belonging to the network is set in order to negotiate and determine the time at which each wireless communication device transmits and receives traffic by setting time information and communication reserved bandwidth information in a beacon frame. It is necessary to transmit all beacon frames transmitted by wireless communication devices other than itself. Therefore, unlike a case where a single control station performs bandwidth management for all wireless communication apparatuses as in a centralized control network, the beacon frame transmission / reception period becomes long.

  On the other hand, the video output device outputs one piece of video data, that is, one frame storing video information (hereinafter referred to as video data frame) at a certain cycle (video frame rate). Unlike the beacon cycle of the wireless communication network, this period is not synchronized with the time when the video output device outputs the video data and the time when the wireless communication device communicates the video data. There is a timing when the beacon periods overlap. At this timing, video data communication is interrupted in order to transmit and receive beacon frames, and there is a problem that the communication throughput is lowered and isochronism cannot be maintained.

  As a system that copes with such a problem, there is a communication system described in Patent Document 1. In this communication system, for the purpose of displaying video at a timing according to the video display standard, a beacon frame received from another wireless communication device is analyzed to predict a period during which the beacon frame is transmitted, During the period, the video data output from the video output device is stored in a buffer in the communication device and controlled so as not to communicate.

  However, in this communication system, since the video information has a large capacity, the capacity of the RAM for buffering the video information becomes very large, and the delay time for transmitting the video information only for the time for transmitting and receiving the beacon frame. There is a problem that occurs.

  The present invention has been made to solve such a problem, and its object is to reduce communication throughput when communicating video information and the like in a wireless communication network composed of a plurality of wireless communication devices. And maintaining isochronism by suppressing transmission delay.

The wireless communication device according to the present invention is used in a wireless communication network including a plurality of wireless communication devices that perform communication conforming to a frame format having a beacon period and a data transfer period and having a predetermined first cycle. A data acquisition means for acquiring data conforming to a frame format having a predetermined second period different from the first period, and comprising a data output period and a data non-output period; Data transmitting means for transmitting data stored in a frame of the data output period acquired by the data acquiring means, beacon frame transmitting / receiving means for transmitting / receiving a beacon frame, and the beacon frame transmitting / receiving means for the data non-output period Performs transmission and reception, and the data transmission means performs transmission during the data transfer period. And means for adjusting the timing so, when returning from hibernation mode, means for determining whether the start time of the beacon frame transmission and reception periods of the radio communication network has changed, based on the determination result by said means self Means for adjusting a start time of a beacon frame transmission / reception period of the device.

  ADVANTAGE OF THE INVENTION According to this invention, when video information etc. are communicated in the radio | wireless communication network comprised by a some radio | wireless communication apparatus, the fall of communication throughput and a transmission delay can be suppressed, and isochronism can be maintained.

It is a figure which shows the structure of the radio | wireless communications system which concerns on embodiment of this invention. It is a block diagram which shows the hardware constitutions of the radio | wireless communication apparatus of the transmission side in the radio | wireless communications system which concerns on embodiment of this invention, and the radio communication apparatus of a reception side. It is a figure which shows the structure of the super frame defined by the WiMedia-MAC standard. It is a figure which shows the video display period and video non-display period in a video data frame. 5 is a timing chart when the beacon frame transmission / reception period is not matched with the video non-display period in the wireless communication system according to the embodiment of the present invention. 5 is a timing chart in a case where a beacon frame transmission / reception period is set to a video non-display period in the wireless communication system according to the embodiment of the present invention. In the wireless communication system according to the embodiment of the present invention, it is a timing chart when switching the wireless communication device on the transmission side when the transmission / reception period of the beacon frame is matched with the video non-display period. It is a figure which shows a beacon frame format. 7 is a flowchart illustrating processing of a wireless communication device that stops transmission when switching a wireless communication device on a transmission side in the wireless communication system according to the embodiment of the present invention. 7 is a flowchart showing processing of a wireless communication apparatus that starts transmission newly when switching a wireless communication apparatus on the transmission side in the wireless communication system according to the embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
<Configuration of wireless communication system>
FIG. 1 is a diagram showing a configuration of a wireless communication system according to an embodiment of the present invention.
This wireless communication system includes three wireless communication devices 1-1 to 1-3 (transmitting stations 1 to 3) serving as transmitting stations (transmitting side) and one wireless communication device serving as a receiving station (receiving side). It consists of three. Each of the wireless communication devices 1-1 to 1-3 includes a video data output unit, and the wireless communication device 3 includes a video data display unit.

  In the description of operations described later, the number of wireless communication devices that transmit video information is limited to one, and when other wireless communication devices output video information, the transmitting station is switched. Can be simultaneously used as a transmission station for video information.

<Configuration of wireless communication device>
FIG. 2 is a block diagram illustrating a hardware configuration of the transmission-side wireless communication device and the reception-side wireless communication device in FIG. 2A is a block diagram of the wireless communication apparatuses 1-1 to 1-3 on the transmission side, and FIG. 2B is a block diagram of the wireless communication apparatus 3 on the reception side.

  Here, for the sake of convenience, the description will be made assuming that the transmitting-side radio communication devices 1-1 to 1-3 and the receiving-side radio communication device 3 have different configurations and functions, but the transmitting-side radio communication device 1 The hardware configuration of the parts other than the video data output unit 16 in -1 to 1-3 and the parts other than the video data display unit 36 in the reception-side wireless communication device 3 are the same. That is, here, functions when the transmission operation and the reception operation are performed will be described.

  The configuration shown in this figure is an example, and a different configuration may be used as long as the function of the present invention can be realized. That is, for example, the video data output unit 16 and the video data display unit 36 may be connected as external devices of the transmission-side wireless communication devices 1-1 to 1-3 and the reception-side wireless communication device 3, respectively.

  The wireless communication device on the transmission side includes a video data processing unit 11, a CPU (Central Processing Unit) 12, a DMAC (Direct Memory Access Controller) 13, a RAM ( Random Access Memory) 14, a wireless communication processing unit 15, and a video data output unit 16.

  The wireless communication processing unit 15 includes a MAC (Media Access Control) unit 17, a signal processing unit 18 connected to the MAC unit 17, an RF (Radio Frequency) unit 19 connected to the signal processing unit 18, and an RF unit 19 And a beacon frame generation unit 21, a beacon frame transmission / reception time adjustment unit 22, and a video frame transmission time adjustment unit 23 connected to the MAC unit 17.

  The video data output unit 16 is means for generating and outputting video data compliant with a predetermined frame format (details will be described later). The video data processing unit 11 is means for acquiring video data from the video data output unit 16 and processing (data compression or the like).

  The CPU 12 is a processor that controls the entire wireless communication apparatus. The DMAC 13 performs data copying by DMA transfer of the video data processed by the video data processing unit 11 to the MAC unit 17 of the wireless communication processing unit 15. The RAM 14 stores a program executed by the CPU 12.

  The MAC unit 17 performs wireless communication protocol control, the signal processing unit 18 modulates the transmission frame, and the RF unit 19 converts the transmission frame into a radio wave and transmits it from the antenna 20. The beacon frame generation unit 21 generates a beacon frame at each beacon frame transmission time described later. In addition, when the device itself transmits a video data frame, it generates a beacon frame in which information for performing a change notification of the beacon frame transmission start time (beacon period change notification) is set. The beacon frame transmission / reception time adjustment unit 22 measures the time when the beacon frame is transmitted, and transmits the generated beacon frame. The video frame transmission time adjustment unit 23 adjusts so that the video data frame is transmitted in a period (data transfer period) other than the beacon period.

  The reception-side wireless communication apparatus includes a video data processing unit 31, a CPU 32, a DMAC 33, a RAM 34, a wireless communication processing unit 35, and a video data display unit 36 that are connected to each other via a data transfer bus 30.

  The wireless communication processing unit 35 includes a MAC unit 37, a signal processing unit 38 connected to the MAC unit 37, an RF unit 39 connected to the signal processing unit 38, an antenna 40 connected to the RF unit 39, and a MAC A beacon frame generation unit 41 connected to the unit 37, a beacon frame transmission / reception time adjustment unit 42, and a video frame reception time adjustment unit 43.

  The video data display unit 36 is means for displaying video data that conforms to a predetermined frame format. The video data processing unit 31 is a means for processing video data (such as data expansion) and outputting it to the video data display unit 36.

  The CPU 32, the DMAC 33, and the RAM 34 have the same configurations and functions as the CPU 12, the DMAC 13, and the RAM 14 in the transmission-side wireless communication device, respectively. That is, the CPU 32 is a processor that controls the entire wireless communication apparatus. Further, the DMAC 33 performs data copy by DMA transfer of video data from the MAC unit 37 to the video data processing unit 31. Further, the RAM 34 stores a program executed by the CPU 32.

  In addition, the MAC unit 37, the signal processing unit 38, the RF unit 39, the antenna 40, the beacon frame generation unit 41, the beacon frame transmission / reception time adjustment unit 42, and the video frame reception time adjustment unit 43 in the wireless communication processing unit 35 are respectively transmitted. The same or corresponding configuration as the MAC unit 17, the signal processing unit 18, the RF unit 19, the antenna 20, the beacon frame generation unit 21, the beacon frame transmission / reception time adjustment unit 22, and the video frame transmission time adjustment unit 23 in the wireless communication device on the side And it has a function.

  That is, the RF unit 39 extracts a received frame from the radio wave received by the antenna 40, the signal processing unit 38 demodulates the received frame, and the MAC unit 37 performs wireless communication protocol control. Further, the beacon frame generating unit 41 generates a beacon frame at every beacon frame transmission time. The beacon frame transmission / reception time adjustment unit 42 measures the time when the beacon frame is transmitted, and transmits the generated beacon frame. When a beacon frame in which a beacon period change notification is set is received, the beacon frame transmission / reception start time is changed from an appropriate super frame (details will be described later) based on the information. The video frame reception time adjustment unit 43 performs adjustment so that the video data frame is received during a period other than the beacon period.

<Superframe configuration>
FIG. 3 is a diagram showing the structure of a super frame defined by the WiMedia-MAC standard.
The super frame is composed of MAS (Medium Access Slot) which is 256 time slots, and one MAS occupies a time of 256 μsec. Further, the super frame includes a beacon period starting from BPST (Beacon Period Start Time) indicating the start time and a data transfer period following the beacon period.

  That is, the first several MASs are assigned to a beacon period, which is a beacon frame transmission / reception period, and all wireless communication devices belonging to the wireless communication network transmit beacon frames in each beacon slot. Each wireless communication device sets the MAS usage status and MAS reservation negotiation information in the beacon frame, and performs transmission / reception of data frames in the MAS after the beacon slot.

  Each wireless communication device constituting the wireless communication network notifies the other wireless communication devices in the same network of the MAS used by the wireless communication device using a beacon frame. At this time, each wireless communication device uses one beacon slot that is vacant in order from the smallest beacon slot number (close to BPST) in the beacon period, and transmits a beacon frame in that period.

  In other words, each wireless communication device secures the MAS and beacon slot that it uses in the first-come-first-served basis. Also, by using the beacon slot numbers in order from the smallest, the beacon period is shortened and the data transfer period is lengthened.

  In the present embodiment, the video data output from the video data output unit 16 of the wireless communication apparatuses 1-1 to 1-3 on the transmission side is changed by changing the number of MASs (changing the length of the superframe period). Each wireless communication device is set to transmit a beacon frame during the frame image non-display period.

<Video display period and video non-display period>
FIG. 4 is a diagram showing a video display period and a video non-display period in a video data frame. As shown in the figure, in the horizontal direction of the video data, the horizontal front porch period Hb and the horizontal back porch period Hc are respectively displayed forward and backward (left and right of the display screen) on the time axis of the horizontal display period Ha. is there. In the vertical direction of the video data, there are a vertical front porch period Vb and a vertical back porch period Vc, respectively, on the front and rear (upper and lower sides of the display screen) of the vertical display period Va.

  Video information is stored in a frame of a horizontal display period Ha and a vertical display period Va, and is output and displayed. On the other hand, video information is neither output nor displayed in the horizontal front porch period Hb, the horizontal back porch period Hc, the vertical front porch period Vb, and the vertical back porch period Vc.

  That is, the horizontal display period Ha and the vertical display period Va become the display period 100, and there are horizontal non-display periods 101 and 102 and vertical non-display periods 103 and 104 before and after the time axis.

  In the present embodiment, the video data output from the video data output unit 16 of the wireless communication devices 1-1 to 1-3 on the transmission side and the video data display unit 36 of the wireless communication device 3 on the reception side are input. The video data has a frame format shown in FIG. Further, as will be described in detail later, the wireless communication processing unit 15 and the reception of the wireless communication devices 1-1 to 1-3 on the transmission side so as to transmit and receive beacon frames during the vertical front porch period Vb and the vertical back porch period Vc. The wireless communication processing unit 35 of the wireless communication device 3 on the side operates.

<When the beacon frame transmission / reception period does not match the video non-display period>
FIG. 5 is a timing chart when the beacon frame transmission / reception period is not matched with the video non-display period in the wireless communication system according to the embodiment of the present invention. In this figure, the delay time associated with video data processing and communication processing in the wireless communication apparatus is ignored (the same applies to FIGS. 6 and 7).

  As shown in the figure, the video data output unit 16 in the wireless communication device 1-1 outputs two video data frames VD11 and VD12. In addition, the wireless communication processing unit 15 of the wireless communication devices 1-1 and 1-2 and the wireless communication processing unit 35 of the wireless communication device 3 transmit beacon frames 221 and 231 and 211, respectively, during the beacon frame transmission / reception period 201. In the beacon frame transmission / reception period 202, beacon frames 222, 232, and 212 are transmitted, respectively.

  In addition, the wireless communication processing unit 15 of the wireless communication device 1-1 transmits the entire video data frame VD11 and a part VD12-1 of the video data frame VD12 during the data transfer period between the beacon frame transmission / reception periods 201 and 202. The remaining VD12-2 of the video data frame VD12 is transmitted during the data transfer period following the beacon frame transmission / reception period 202. The video data transmitted from the wireless communication processing unit 15 of the wireless communication device 1-1 is received by the wireless communication processing unit 35 of the wireless communication device 3.

  In this case, the beacon frame transmission / reception periods overlap during the video data frame communication time, and the video data communication is stopped halfway and the beacon frame is transmitted / received (video data frame VD12- in the figure). 1, VD12-2). Therefore, it is necessary to buffer the video data from the video data output unit 16 in the RAM 14 during a period during which beacon frames are transmitted and received (beacon frame transmission / reception period 202 in the figure). In addition, it becomes difficult to ensure isochronism in video data communication.

<When the beacon frame transmission / reception period is set to the video non-display period>
Therefore, in the wireless communication system according to the present embodiment, in order to solve this problem, the transmission / reception period of the beacon frame is matched with the video non-display period.

  FIG. 6 illustrates a case where the beacon frame transmission / reception period is adjusted so that the beacon frame is transmitted / received during the video non-display period in the wireless communication system according to the embodiment of the present invention. It is a timing chart in the case.

  As shown in the figure, the video data output unit 16 in the wireless communication device 1-1 outputs three video data frames VD11, VD12, and VD13. In addition, the wireless communication processing unit 15 of the wireless communication devices 1-1 and 1-2 and the wireless communication processing unit 35 of the wireless communication device 3 transmit beacon frames 321 and 331, and 311 respectively during the beacon frame transmission / reception period 301. In the beacon frame transmission / reception period 302, beacon frames 322, 332, and 312 are transmitted, respectively.

  The wireless communication processing unit 15 of the wireless communication device 1-1 transmits all of the video data frames VD11 and VD12 during the data transfer period between the beacon frame transmission / reception periods 301 and 302, and continues to the beacon frame transmission / reception period 302. The entire video data frame VD13 is transmitted during the data transfer period. The video data frame transmitted from the wireless communication processing unit 15 of the wireless communication device 1-1 is received by the wireless communication processing unit 35 of the wireless communication device 3.

  As described above, since the video data is wirelessly communicated during the video display period and the beacon frame is transmitted / received during the video non-display period (Vc + Vb), the beacon transmission / reception may not be performed during the transfer of the video data frame. Therefore, the video data frame from the video data output unit 16 need not be buffered in the RAM 14. Also, isochronism is ensured by video data communication.

  In FIG. 6, the video data frame is transmitted twice in one superframe period. However, as long as one beacon period is set to a multiple of the period in which the video data output unit 16 outputs one piece of video data, this number is limited. There is no. Although not shown, not only the beacon frame but a frame other than the video data frame such as a control frame for controlling the network may be transmitted during the video non-display period.

<Switching the wireless communication device on the transmission side>
FIG. 7 is a diagram illustrating a wireless communication system according to an embodiment of the present invention. When the transmission / reception period of the beacon frame is set to the video non-display period, the wireless communication apparatus on the transmission side is switched; It is a timing chart when adjusting a beacon frame transmission / reception period so that transmission / reception may be performed and switching a wireless communication apparatus on the transmission side. Here, a case is shown in which the wireless communication device (transmission station) that transmits video data is switched from the wireless communication device 1-1 (transmission station 1) to the wireless communication device 1-2 (transmission station 2).

  FIG. 8 is a diagram showing a beacon frame format. This figure is an excerpt of only the part (ASIE) related to the beacon period change notification. As illustrated, in this format, “the number of superframes until the beacon frame start time is changed” and “beacon start time” can be set. Here, the “beacon start time” is a time at which transmission / reception of a beacon frame is started, that is, a start time of a beacon frame transmission / reception period.

  In FIG. 7, the operation of each wireless communication apparatus in the beacon frame transmission / reception periods 301 to 302 is the same as that in FIG. Next, the following operation is executed with the transmission station switching period Pa as the interval between the beacon frame transmission / reception period 302 and the beacon frame transmission / reception period 303.

  That is, the wireless communication apparatus 1-2 uses the ASIE of the beacon frame before outputting the video data frame, and “the number of superframes until the beacon start time is changed” and “the beacon start offset time (the current beacon start time). The time from the time to the beacon start time after change) ”is transmitted, and the beacon start time is changed to all wireless communication devices belonging to the wireless communication network. Notice. When the number of superframes set in ASIE elapses, the beacon start time is changed from the next superframe, and at the same time, the wireless communication device 1-2 starts transmitting the video data frame VD21. FIG. 7 shows a case where the wireless communication apparatus 1-2 notifies that the beacon start time is changed using the ASIE of the beacon frame 333 transmitted in the beacon frame transmission / reception period 302 (performs a beacon period change notification). Yes.

<Processing flow when switching the wireless communication device on the sending side>
<< Processing of the wireless communication device that stops transmission >>
FIG. 9 is a flowchart showing processing of the wireless communication apparatus that stops transmission when the wireless communication apparatus on the transmission side is switched in the wireless communication system according to the embodiment of the present invention. That is, the flow in this figure is the processing of the wireless communication apparatus 1-1 in FIG.

  The wireless communication device 1-1 transmits and receives a beacon frame during the video non-display period, transmits video data during the video display period (step S1), and determines whether or not a beacon of a beacon period change notification is received (step S1). S2).

  When a beacon for notification of change in beacon period is received (step S2: YES), the number of superframes (N) in the beacon frame and the beacon start offset time are acquired (step S3), and transmission of video information is stopped (step S4). ).

  Next, a count value i of a counter for counting the number of super frames (hereinafter referred to as a super frame counter) is reset to 0 (step S5), and every time the super frame period ends (step S6: YES), the count of the super frame counter is counted. The value i is incremented (step S7).

  When the count value i of the superframe counter reaches the number of superframes (N) set in the received beacon frame (step S8: YES), that is, “the number of superframes until the beacon start time is changed” is superposed. When the frame period elapses, transmission / reception of a beacon frame is started from the next superframe at a time that matches the “beacon start offset time” set in the received beacon frame (step S9).

<< Processing of the wireless communication device that starts transmission >>
FIG. 10 is a flowchart showing processing of the wireless communication apparatus that starts transmission anew when switching the wireless communication apparatus on the transmission side in the wireless communication system according to the embodiment of the present invention. That is, the flow in this figure is the processing of the wireless communication apparatus 1-2 in FIG.

  The wireless communication device 1-2 that is not transmitting video data enters hibernation mode (sleep mode), which is one of the power saving modes, when there is no operation for a certain period of time from an external switch, button, or the like (not shown). The hibernation mode is continued until there is an external trigger for transmitting video data from an external switch, button, or the like (step S11: NO → step S12).

  When there is an external trigger for transmitting video data (step S11: YES), the scan mode is restored after returning to the normal mode (step S13), and the beacon start time on the wireless communication network is changed while in the hibernation mode. It is determined whether it has been performed (step S14).

  If it has been changed as a result of the determination (step S14: YES), the beacon start time is changed by adjusting the time of the internal timer set before entering the hibernation mode (step S15), and the superframe The count value i of the counter is reset to 0 (step S16).

  Next, the beacon frame in which the beacon period change notification is set, that is, “beacon period change notification”, “number of superframes until the beacon start time is changed (N)”, and “beacon start offset time” are stored. The transmitted beacon frame is transmitted (step 17).

  Thereafter, every time the super frame period ends (step S18: YES), the count value i of the super frame counter is incremented (step S19), and the count value i of the super frame counter is transmitted by the beacon frame transmitted in step S17. Steps S17 to S19 are repeated until the number of superframes (N) set in (Step S20: NO → S17 → S18 → S19 → S20).

  Here, the reason for repeating step S17 is to ensure that the wireless communication terminal device on the wireless communication network receives the beacon frame in which the beacon period change notification is set. Each time step S17 is executed, the number of superframes (N) set in the beacon frame is decremented.

  When the count value i of the superframe counter reaches the number of superframes (N) set in the beacon frame transmitted in step S17 (step S20: YES), the beacon offset time set in the beacon frame transmitted in step S17 is the beacon. The start time is set (step S21), transmission / reception of a beacon frame is started from that time, and transmission of video data is started in a data transfer period following the beacon period including that time (step S22).

  If the beacon start time in the wireless communication network has not been changed while in hibernation mode (step S14: NO), beacon frames are transmitted and received at the same timing, and video is transmitted during the data transfer period following the beacon period. Data transmission is started (step S22).

  In the processing described above, analysis of the received beacon frame, determination of the beacon slot number used for transmission, generation of the beacon frame, generation of parameters such as ASIE in FIG. 8 may be performed by the CPUs 12 and 32. it can.

  In the embodiment described above, the present invention is applied to a system that performs wireless communication of video information. However, the present invention is not limited to video information, and wireless communication of information that requires isochronism such as audio information. It is also applicable to a system that performs

  1-1 to 1-3: wireless communication device on transmission side, 3 ... wireless communication device on reception side, 16 ... video data output unit, 15, 35 ... wireless communication processing unit, 21, 41 ... beacon frame generation unit, 22 , 42 ... beacon frame transmission / reception time adjustment unit, 23 ... video frame transmission time adjustment unit, 36 ... video data display unit, 43 ... video frame reception time adjustment unit, 100 ... display period, 101 to 104 ... non-display period.

JP 2011-234166 A

Claims (7)

A wireless communication device used in a wireless communication network including a plurality of wireless communication devices that perform communication conforming to a frame format having a beacon period and a data transfer period and having a predetermined first cycle,
Data acquisition means for acquiring data conforming to a frame format having a predetermined second period different from the first period, the data output period and a data non-output period;
Data transmitting means for transmitting data stored in the frame of the data output period acquired by the data acquiring means;
Beacon frame transmission / reception means for transmitting / receiving a beacon frame;
Means for adjusting the timing so that the beacon frame transmission / reception means transmits and receives during the data non-output period and the data transmission means transmits during the data transfer period;
Means for determining whether the start time of the beacon frame transmission / reception period on the wireless communication network is changed when returning from the hibernation mode;
Means for adjusting the start time of the beacon frame transmission / reception period of the own device based on the determination result by the means;
A wireless communication device comprising: The wireless communication device according to claim 1,
A wireless communication apparatus, wherein the data is video data. The wireless communication device according to claim 1 or 2,
A wireless communication apparatus comprising means for setting the first period to a multiple of the second period. The wireless communication apparatus according to any one of claims 1 to 3,
A radio comprising means for transmitting a beacon frame for a beacon period change notification including a start time of a beacon frame transmission / reception period set so that a beacon frame is transmitted during the data non-output period when the data transmission means starts transmission Communication device. The wireless communication apparatus according to any one of claims 1 to 4,
A wireless communication apparatus comprising means for setting a beacon frame transmission / reception period of its own device at the start time when a beacon frame change notification including a beacon frame transmission / reception period start time is received. Consists beacon period and a data transfer period, and a radio communication method in a more composed wireless communication network to a plurality of wireless communication device that performs communication conforming to the frame format having a predetermined first period,
A step in which the wireless communication device on the transmission side acquires data conforming to a frame format having a predetermined second period that is different from the first period and includes a data output period and a data non-output period;
A beacon frame transmission / reception step in which the transmission-side wireless communication device and the reception-side wireless communication device transmit and receive a beacon frame during the beacon period; and
A data transmission step in which the wireless communication device on the transmission side transmits data stored in a frame of the data output period;
The transmitting wireless communication device and the receiving wireless communication device transmit and receive the beacon frame during the data non-output period, and the transmitting wireless communication device transmits and receives the data output period during the data transfer period. Adjusting the timing to transmit the data stored in the frame;
Determining whether the start time of the beacon frame transmission / reception period on the wireless communication network is changed when the wireless communication device on the transmission side returns from hibernation mode;
The wireless communication device on the transmitting side adjusts the start time of the beacon frame transmission / reception period based on the determination result of the step;
Wireless communication method Ru equipped with. Data output to a wireless communication device used in a wireless communication network composed of a plurality of wireless communication devices that perform communication conforming to a frame format having a beacon period and a data transfer period and having a predetermined first cycle A step of acquiring data compliant with a frame format having a predetermined second period different from the first period, and a beacon frame transmitting / receiving step of transmitting and receiving the beacon frame; A data transmission step of transmitting data stored in a frame of a data output period; transmitting and receiving the beacon frame in the data non-output period; and data stored in the frame of the data output period in the data transfer period The process of adjusting the timing to transmit and hibernation A step of determining whether or not the start time of the beacon frame transmission / reception period on the wireless communication network has been changed when returning from the mode, and the start time of the beacon frame transmission / reception period of the own device based on the determination result of the step And a program for executing the process .

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