Position Optimization of Movable Auxiliary Receive Antenna for Co-site Interference Cancellation

Co-site interference in multi-radio systems, caused by insufficient isolation between high-power transmitters and receivers, induces deterioration of receiver communication performance. While existing co-site interference cancellation methods rely on fixed-position auxiliary receive antennas (ARA) requiring additional radio frequency (RF) cancellation circuits, this paper proposes a hardware-efficient movable auxiliary receive antenna (MA-ARA) interference cancellation (IC) method, which can minimize residual interference power by dynamically optimizing the position of MA-ARA. First, a position optimization model is formulated, followed by the closed form expression for residual interference power related to the position of MA-ARA is derived in dual-interference scenarios. Subsequently, swarm intelligence algorithms are utilized to solve the position optimization problem. Results demonstrate a 50.93 dB interference cancellation ratio (ICR) and 35.19 dB SINR improvement of dual-interference scenarios which is 80% faster convergence than brute force algorithm (BFA), and 60.03 dB ICR of single-interference scenarios which is 7dB higher than that of conventional RF cancellation method, confirming the effectiveness of the MA-ARA position optimization method.