Field Experiments on Pilot Symbol-Assisted Coherent Multistage Interference Canceller in DS-CDMA Reverse Link

摘要

This paper presents the results of field experiments on the pilot symbol assisted (PSA) coherent multistage interference canceller (COMSIC) receiver in the direct sequence code division multiple access (DS-CDMA) reverse link. The implemented COMSIC receiver comprising three cancellation stages employs PSA channel estimation and replica generation of multiple access interference (MAI) of other users. The experimental results demonstrate that the COMSIC receiver associated with antenna diversity reception and fast transmission power control (TPC) exhibits effectiveness in suppressing severe MAI in actual multipath fading channels. The transmission power of a mobile station (MS) when the COMSIC receiver is employed at a base station (BS) is reduced by approximately 2.0 and 4.0 dB compared to that with the matched filter (MF)-based Rake receiver when the ratios of the target signal energy per bit-to-interference power spectrum density ratio (E_b/I_0) of the desired user to the target user are Δ_(target) = -6 and -9 dB, respectively. Furthermore, for the COMSIC receiver, the transmission power of a MS at the average bit error rate (BER) of 10~(-3) with antenna diversity is decreased by approximately 7.5 and 11 dB compared to that without antenna diversity when the Δ_(target) values are -6 and -9 dB, respectively.