Delay Model Analysis Of The CBN-ARQ Based On Noisy Channels And Multiple Relays

The technology of error control in the data link layer is an important content on theresearch of wireless communication. GBN-ARQ is one of the reliable and efficient data errorcontrol technology and the paper will give an exact analysis on the delay performance of themulti-channels and multiple relays GBN-ARQ based on Rayleigh fading.Firstly, the development background of error control technology and the researchsituation of GBN-ARQ scheme in the wireless communication are described. Meanwhile, thelink transmission efficiency of the three basic ARQ schemes is systematically analyzed.Secondly, taking the arriving packets at the slot of sending packet and different packeterror rates in different sub-channels into consideration, we mainly model the multiple parallelchannel GBN-ARQ scheme over Rayleigh fading channel as M/G/1and exactly analyze itsdelay performances with the Markov chain, where the system state is described solely by theaverage packet queue length. In analyzing, this paper revises the former relations between thearriving packets when the system is under idle and busy; we strictly decompose the statetransition probability in terms of the revised relations and take Binomial distribution exactlyto compute the transition probability when h packets are sent but only t packets aretransmitted successfully on any t sub-channels. Finally, the expressions of the average delayand throughput are obtained by solving the steady distribution. The MATLAB numericalsimulation on delay performance shows that a smaller service delay would be provided withthis system, especially in the case of higher channel error rate.Finally, taking the noise channels and the limited numbers of retransmission of dataframes in actual communication in to consideration, the paper model the multiple RelaysGBN-CARQ system as M/G/1in the wireless networks over Rayleigh fading channel. Afterexactly analyzing the probability distribution of transmitting frames successfully, theexpressions of the average transmission delay, the minimum numbers of Relays and theminimum sliding window length are obtained. Meanwhile, the method of determining theminimum numbers of Relays and the minimum sliding window length in a given situation isobtained, so that we could control the system effectively. The system simulation shows thatreducing the number of relays node will reduce the system transmission delay but increase theprobability of frame loss.