Impact of Phase Noise on Sidelobe Cancellation System Utilizing Distributed Phase-Lock-Loops

Abstract

|Phase noise is a common hardware impairment that affects the performance of beamforming systems. Therefore, analysis of its impact is of great practical interest. Although Sidelobe Cancellation (SLC) is a mature technique, existing analyses typically ignore the effect of phase noise, due to the shared assumption that the down-conversion circuits have a common local-oscillator (LO). However, when distributed phase-lock-loops (PLLs) are used, the impact of phase noise cannot be neglected. Therefore, this paper derives new mathematical models of performances, including signal-to-interference-plus-noise ratio (SINR) and beamforming gain. Exact and approximated analytical models are obtained, respectively. In addition, we propose an average beam pattern formula to replace the traditional beam pattern formula, to improve the consistency between beam null depth and the beamforming gain. The theoretical (cid:12)ndings are veri(cid:12)ed through signal-level simulations.