Investigation of the SINR behavior of the beamforming-applied cellular CDMA base station receiver

This paper presents the analytic derivations and the operation simulations of the SINR behavior when a linear array antenna is accommodated into the cellular CDMA base station with beamforming (BF) algorithms. The roles of the two major performance affecting design factors, i.e., the direction selectivity of an array antenna and the direction-of-arrival (DOA) precision in the BF algorithm, are investigated not only in view of the SINR itself but also in view of the BF algorithm´s robustness to the erroneous factors of spatial scattering of radio waves and DOA error. It is confirmed from this study that there exists trade-off characteristics between the SINR and the robustness with respect to the two design factors. The trade-off characteristics can be capitalized to obtain an economic means of BF implementation for cellular CDMA system which does not severely deteriorate SINR performance while ensuring its robustness to the erroneous factors