Performance Evaluation on Interference-Resistance of a Multi-Gbps WPAN 60GHz System

摘要

This paper presents the performance evaluation of a multi-Gbps 60GHz single carrier wireless personal area network (WPAN) system in the presence of adjacent channel interference (ACI). ACI is generated by spectral-regrowth from spectrum bands occupying adjacent channels. The presence of ACI significantly compromises system performance. In this paper, it is found that the signal modulation type changes the tolerance of the system against ACI. Additionally, radio frequency (RF) component impairment such as power amplifier (PA) non-linearity is a major factor affecting the generation of ACI. For a quadrature-phase-shift-keying (QPSK) system, a 0.5dB signal to noise ratio (SNR) degradation is observed with ACI=15dB, whereas for a 16-quadrature amplitude modulation (QAM) system, the same degradation is observed with ACI as low as 5dB. With the presence of ACI=0dB in a 16-QAM system, the employment of an RF 60GHz PA with output back-off (OBO) = 5dB outperforms 2dB over that with OBO=3dB. For a modulation with constant envelope such as π/2-binary phase shift keying (BPSK) system, error floor for bit error rate (BER) is not observed until ACI extends beyond 25dB. It is also found that phase noise significantly degrades system performance especially that of the 16-QAM by causing error floor at ACI as low as OdB.