Distributed interference alignment in high-speed railway wireless access system

According to the characteristics of high-speed railway, we propose a scheme of wireless communication access system based on distributed interference alignment. This system contains two sets of dual-antenna integrated access units inside the train. It can support four users accessing to the high-speed railway wireless access system simultaneously. The integrated access unit can separate expected signal from interference signal. Simulation results show that this inside access system can obtain totally four degrees of freedom and its performance of bit error rate is better than that without adopting this interference alignment technology. Moreover, the performance of downlink bit error rate is slightly better than its uplink´s.