An active integrated circuit wireless interference cancellation solution

Abstract

This paper proposes a novel active interference cancellation system that allows simultaneous operation of multi-standard collocated radios. This method can be extended to other mutually interfering radio devices. A reference signal correlated to the original interferer is used to generate a cancellation signal by means of amplitude and phase alignment, and filtration. The filter employed emulates the coupling channel responsible for interference. An implementation of this procedure in 0.18 micrometer Si-CMOS IC technology is also presented. The circuits fabricated are tunable and are controlled externally by a closed loop adaptive process including an error minimization method. The cancellation system designed achieves 15-30 dB of interference suppression for different cases. A total power of 14 mW is dissipated by the CMOS ICs designed.