小扩频系数下的多级非线性并行干扰删除器的衰减系数

Attenuation Factors of Multistage Non-linear Parallel Interference Cancellation with Small Spread Factors

并行干扰删除器由于较佳的性能和较低的复杂度已开始逐步实用化 .在日本 ,并行干扰删除器已用于3G的演示系统当中 .但由于 3G系统存在较小的扩频系数 ,并行干扰删除器的干扰再生的方法和结构必须加以调整 .本文针对CDMA系统在频率选择性瑞利衰落信道中 ,小扩频系数下多级非线性并行干扰删除器的干扰再生的问题 ,明确了衰减系数的概念、产生原因 ,提出了一种新型应用衰减系数的多级非线性并行干扰删除器 (PIC)方案 .此外 ,还详细分析了小扩频系数下衰减系数下多级非线性并行干扰删除器性能的提高 .最后 ,本文给出了衰减系数的仿真实现 。

Parallel interference cancellators have been used gradually because of their better performance and lower complexity, for example, in 3G demo systems of Japan. The approaches of regenerating interference and structures of parallel interference cancellators must be adjusted for the sake of small spread factors of 3G systems. Aiming at the question of interference regeneration of multistage non-linear parallel interference cancellators with small spread factors for frequency selective Rayleigh fading CDMA systems, we proposed a concept of attenuation factors, reasons and a novel scheme of multistage non-linear parallel interference cancellation (PIC) based on attenuation factors. Moreover, we analyze in detail the performance of multistage non-linear PIC with small spread factors, which benefits from attenuation factors. And simulation results show that to what extent the performance of the novel multistage non-linear PIC based on attenuation factors can be improved.