一种新的软判决度量及其在多径衰落信道中的性能(英文)  

Performance of Generalized Soft Decision Metric Without Noise Variance Knowledge over Multipath Fading Channel

作　　者：李强[1] 毕光国[1] 杜鹏[1] 

机构地区：[1]东南大学移动通信国家重点实验室,江苏南京210096

出　　处：《应用科学学报》2004年第3期273-278,共6页Journal of Applied Sciences

基　　金：Project Supported by 86 3 Program of China Under Grant (2 0 0 1 AA1 2 3 0 1 5)

摘　　要：提出了一种新的简化软判决度量,并进一步推广到一般的p范数情形,得到了广义的简化软判决度量生成办法.同时给出了几种不同参数下LDPC编码的16QAM/64QAM系统的误比特率性能的计算机仿真结果.仿真结果表明,无论是在AWGN信道还是在多径衰落信道中,所提出的简化方法都没有性能损失.更重要的是,由于无需噪声方差估计,该方法可以简化系统实现,大大降低了实现的复杂度.进一步的计算机仿真显示,在高信噪比的多径信道中,当p略小于2时,广义的简化软判决度量比传统方法的误比特率性能要好.A new simplified soft decision metric, without noise variance knowledge, is derived in this paper. By recognizing that it is simply a distance metric in Euclidian space, we further generalize it to p-norm. Performance comparisons are presented for LDPC coded 16QAM/64QAM with different parameters. Simulation results show that, as compared with the simplified soft decision metric reported in ref.[6], there is no performance loss with our proposed generalized soft decision metric for both AWGN and multipath fading channel. Moreover, it is unnecessary to estimate noise variance at channel output, which greatly facilitates practical implementation. Further simulation indicates that, in multipath fading channel, a performance gain can be obtained with p a bit less than 2 at high signal to noise ratio.

关 键 词：软判决度量 多径衰落信道 低密度校验码 LDPC编码 误比特率 

分 类 号：TN911[电子电信—通信与信息系统]