Abstract:

An adaptive selective repeat automatic repeat request scheme in correlated Rayleigh fading channel is proposed. For this algorithm, we adapt the transmission modes or packet size to the channel state variation. Closed form expression of throughput efficiency of ideal and non-ideal adaptive selective repeat ARQ is derived using multi state Markov system model defined according to both channel state and transmission mode. Further,Optimum packet length corresponding to transmission mode and optimum channel state transition estimation parameters are explored. Simulation results demonstrate with the optimum packet lengths and optimum channel state transition estimation parameters, the throughput efficiency is very close to ideal adaptive SR ARQ and higher than those with non optimum parameters schemes in a wide range of signal to noise ratio.

Key words: correlated Rayleigh fading channel, Markov model, adaptive SR ARQ, throughput