Realistic simulations of CDMA mobile radio systems using joint detection and coherent receiver antenna diversity

Due to time variant multipath propagation, both intersymbol interference and multiple access interference occur at CDMA receivers. These degrading effects can be combatted by joint detection (JD) techniques. In order to reduce the performance impairments resulting from time variance, coherent receiver antenna diversity (CRAD) can be used. A system model of CDMA mobile radio systems using various JD techniques in combination with CRAD is introduced. This system model is an evolution of the pan-European GSM and takes important real world aspects such as imperfect channel estimation, nonlinear amplification and D/A and A/D conversion into account. The viability of JD with CRAD is demonstrated by bit error rate simulations of this system model. It is shown that by using JD with two receiver antennas in bad urban areas, E_b/N₀<8 dB per antenna is sufficient for a bit error rate of 10^-2, and E_b/N₀<11 dB per antenna is required for a bit error rate of 10^-3