Optimal single-relay distributed opportunistic channel access method under delay constraint

Abstract

The invention discloses an optimal single-relay distributed opportunistic channel access method under delay constraint. The method comprises the following steps that: each information source competesfor a channel, when only one information source exists, the information source obtains a channel access opportunity, otherwise, all the information sources restart channel competition; after the information source i competes successfully, the relay receives the RTS packet sent by the information source i, calculates the channel quality from the information source i to the relay, then sends the RTSpacket to the information sink i, the information sink i replies to the relay after receiving the RTS packet, and the relay node calculates the channel quality from the relay to the information sinki; the relay node feeds back all information to a signal source i, and the signal source i calculates the maximum transmissible rate and makes a decision: selecting an access channel, and selecting anoptimal single relay capable of reaching the maximum rate to perform channel access by the signal source i; otherwise, the information source i gives up the channel opportunity, and all the information sources compete for the channel again. According to the method, the user diversity and the time diversity are fully utilized, and the system throughput and the spectrum utilization rate are effectively improved.

Description

technical field [0001] The invention relates to the technical field of wireless communication, in particular to an optimal single-relay distributed opportunistic channel access method under delay constraints. Background technique [0002] With the continuous development of the times and the continuous innovation of science and technology, modern society has higher and higher requirements for the communication quality of wireless networks, which are embodied in the real-time, high efficiency and reliability of information transmission. As a result, the demand for resources has also doubled, and the problem of insufficient spectrum resources has become increasingly serious, which will seriously restrict the development of future wireless networks. In order to solve such problems, the most direct and effective methods include developing new spectrum and improving the utilization rate of existing spectrum. However, due to the constraints of existing technologies, it is difficul...

AI Technical Summary

Problems solved by technology

[0004] In the traditional wireless network, the standard protocol studies the media access control layer and the physical layer independently. This method is simple in design and the overhead generated between layers is low, but because the media access control layer does not consider the channel Status information, users with poor channel status will occupy the channel at a low rate for a long time. At this time, even if there are users with good channel status who need to transmit, they can only enter the waiting state until the channel is free to access the channel. However, Since the channel state changes dynamically over time, the channel state of the user may be poor when accessing the channel

Therefore, independent research on each layer is difficult to meet the design requirements of improving system throughput and system service quality, and the spectrum utilization rate cannot be effectively improved.

[0005] In addition, most of the existing methods of opportunistic channel access only consider the throughput performance of channel access, and do not analyze based on usage scenarios

For example, in some actual scenarios, many video applications and voice applications have different delay requirements, and even some applications have extremely low tolerance for delay. When the user exceeds the given delay constraint, even if the channel is in good condition, It is meaningless to perform channel access again, but seriously reduces the video or voice performance, thus affecting the overall service quality

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