OFDM interfering signal rejection from 802.11ac channel

Efficient utilization of the IEEE 802.11ac 80 and 160 MHz channels has been considered recently. In this paper it is shown, how the successive interference cancellation (SIC) method can be used in a 80 MHz receiver to reject the interfering legacy 802.11a/n OFDM signal occupying any secondary 20 MHz channel inside the 80 MHz 802.11ac channel. The method can be also utilized in 160 MHz receiver in a similar manner. The simulation shows, that if the conditions specified in the paper are fulfilled then no frequency guard band is necessary between the interfering OFDM signal and the desired OFDM signal occupying the remaining part of the 802.11ac 80 MHz channel. Both OFDM signals, the interfering and the desired one, are transmitted with no symbol timing synchronization. The simulation results show that two or three iterations are enough to completely reject the interfering OFDM signal by the 80 MHz (or 160 MHz) receiver.