Abstract: In order to improve the fairness between uplink and downlink flows in AP optimization, a novel algorithm called FOUD(fairness over uplink and downlink) is proposed.Considering the influence of the attempt limit and the bit error rate of wireless, the FOUD algorithm modeling of AP and wireless stations is studied separately by using two-dimensional Markov chain, which derives the probability of data sending under the condition of different bit error rate and different number of uplink and downlink flows. Simulation results show that FOUD can improve the fairness of the uplink and downlink bandwidth as well as the throughput.

Key words: heterogeneous network, fairness between uplink and downlink flows, intelligent AP, dynamic probabilistic sending mechanism