Radio communication system, radio communication device, radio communication method, and computer program

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E04707619

21-01-2015

<dl><dt>PRIORITY TRANSMISSION </dt><dd>ORDER </dd></dl>

<dl><dt>THERE IS TRANSMISSION OF DATA </dt><dd>RTS SIFS + Backoff AFTER THE CONCLUSION OF THE TRANSMISSION OF THE PRIORITY TRANSMISSION RIGHT OF THE COMMUNICATIONS STATION </dd></dl>

<dl><dt>TRANSMISSION OF BEARINGS TO FOR COMMUNICATIONS STATION </dt><dd>ORDER </dd></dl>

<dl><dt>NO RIGHT OF TRANSMISSION </dt><dd>THERE IS NO TRANSMISSION OF DATA RTS FIFS + Backoff AFTER THE CONCLUSION OF THE TRANSMISSION OF THE PRIORITY TRANSMISSION RIGHT OF THE COMMUNICATIONS STATION </dd></dl>

<dl><dt>WITH PRIORITY </dt><dd>BEARING TRANSMISSION AA COMMUNICATION STATION ORDER </dd></dl>

<dl><dt>ALL </dt><dd>THERE IS DATA TRANSMISSION DATA SIFS SPACE AFTER CTS IS RECEIVED </dd></dl>

<dl><dt>COMMUNICATION STATIONS </dt><dd>DATA RECEIVED ACK SIFS SPACE AFTER THE DATA WAS RECEIVED </dd></dl>

With respect to the transmission of packets within the TPP of the local station, the communications station is also allowed to transmit the packet in the LIFS space. In addition, with respect to the transmission of the packet within the TPP of another station, another station transmits the packet in the FIFS + backoff space. Although the FIFS + backoff space is constantly used as the packet space in the IEEE802.11 system, in accordance with the arrangement of this embodiment, this space can be narrowed and thus, a more effective packet transmission becomes possible. .

Furthermore, although each communication station transmits a beacon fundamentally in each superframe period, depending on the cases, it is allowed to transmit a plurality of beacons or a signal similar to the beacon and can acquire the TPP each time it transmits these beacons. In other words, the communications station can maintain the priority transmission resources corresponding to the number of beacons transmitted in each superframe. In this case, the beacon that the communications station constantly transmits at the beginning of the superframe period is referred to as an "ordinary beacon" and the beacon that follows the second beacon that is transmitted at another timing, in order to acquire the TPP or for other purposes, it is referred to as an "auxiliary beacon."

TPP USE APPLICATION:

When the TPP is defined as 480 [µ sec], 21 packets corresponding to 60 [bytes] can be transmitted or approximately one packet of 6000 [bytes] can be transmitted. More specifically, even when the support means are congested, the transmission of approximately 21 ACK packets in 80 [milliseconds] can be guaranteed. Alternatively, when only TPP is used, a transmission line of 600 [kpbs] = (6000 [bytes] / 80 [msec]) can be kept at the lowest level. Although the priority transmission right is granted to the communications station in the TPP as described above, the priority transmission right is granted to a communications station that is called by the communications station in the TPP. Although the transmission has priority in the TPP fundamentally, when the communications station does not have any information to be transmitted, but it is clear that another station has information to be transmitted to the local station, a paging message or a paging message. Polling message can be transmitted to said "other station":

On the contrary, when the local station does not have any information to be transmitted even if it has transmitted the beacon and the communications station is not aware of the fact that another station has information to be transmitted to the local station, the previous communication station does nothing. , rejects does nothing, rejects the transmission priority granted by TPP and does not transmit any information. Then, after the LIFS + backoff or FIFS + backoff time has elapsed, another station starts transmission even in this time zone.

Having considered the arrangement in which the TPP is followed immediately after it can transmit the safety beacon is illustrated in Figure 16, it is preferable that the beacon transmission timing of each

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