An 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 constraints. The method is: each information source competes for the channel. When there is only one information source, the information source gets the channel access opportunity, otherwise, all information sources start the channel competition again; when the information source i competes successfully, the relay will receive the information The RTS packet sent by source i calculates the channel quality from source i to relay, and then relay sends an RTS packet to sink i, and sink i replies to the relay after receiving it, and the relay node calculates the channel quality from relay to sink i ; The relay node feeds back all the information to the source i, and the source i calculates the maximum transmission rate and makes a decision: select the access channel, and the source i will select the optimal single relay that can achieve the maximum rate for channel access; Otherwise, source i gives up the channel opportunity, and all sources re-compete for the channel. The invention fully utilizes user diversity and time diversity, and effectively improves system throughput and frequency spectrum utilization.

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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