A comparative study of code acquisition using antenna diversity and beamforming techniques

We compare code acquisition using a receiver with multiple antennas in a frequency nonselective fast Rayleigh fading channel. Two different approaches are evaluated; a receiver based on m-antenna diversity and a receiver based on an m-element antenna array exploiting beamforming techniques. The beamforming approach is basically a two-dimensional (2D) search in the delay-angle domain. In both cases, an equal number of m correlating elements is considered. Results are presented as a function of m. First, theoretical models to evaluate system performance are presented. Then, performance figures are obtained through numerical simulations. It is found that, in low signal-to-noise ratio (SNR) scenarios, the diversity scheme provides best performance for all m. As SNR increases, the diversity approach is slightly outperformed by the beamforming scheme for low values of m. For larger SNR, performance figures in both cases are to some extent similar.