【摘要】 研究了基于LS码和Walsh码多天线CDMA系统在干扰方差已知和干扰方差未知2种情况下的容量,给出了理论分析.仿真结果表明,使用LS码的系统容量远远大于基于使用Walsh码的CDMA系统;干扰方差对LS码系统没有任何影响,容量与信噪比呈线性关系;而对于传统CDMA系统,干扰方差未知要损失一定的容量,并且在信噪比大于18 dB时有平台效应.更多还原

【Abstract】 The capacity of multi-antennas CDMA systems with LS codes and Walsh codes under known and unknown interference covariance is analyzed theoretically.Both theoretical and simulation results show that the capacity of CDMA systems based on LS codes is much larger than that on Walsh codes;the interference covariance has no influence on capacity for LS CDMA systems,and capacity is linear with SNR when using multi-code detection;but it will loss certain capacity under unknown interference covariance for conventional CDMA systems,and form a floor when SNR is great than 18?dB.更多还原