Adaptive Antenna Array Based Non-Cooperative Co-Channel Interference Cancellation System for Ultrashort Wave Radios and Non-Ideality Analysis

Interference cancellation holds great promising to suppress the non-cooperative interference. However, it is usually difficult to obtain an ideal copy of the non-cooperative interference since its statistical characteristics are unknown. A novel adaptive antenna array based non-cooperative co-channel interference cancellation system for ultrashort wave (USW) radios is proposed in this article. By adopting the auxiliary antenna array, the designed system realizes blind interference extraction from the received mixed signal based on the constrained maximum variance criterion. Then, the extracted interference is assigned as the reference signal to realize interference cancellation of the received signal in the reference antenna channel. Meanwhile, the non-ideality characteristics including nonlinearity and IQ imbalance in the receiver chain are taken into account. A widely linear least mean square (WLLMS) model based on Volterra series is introduced in the cancellation process. As a blind method, no extra reference signal and specified array structure are required in this proposed system. Simulation and experimental results validate the effectiveness of the proposed scheme, which implies comparatively strong practicality in non-cooperative co-channel interference cancellation for USW radios in engineering.