摘要
本文针对采用Gray映射的高阶PSK调制,提出一种比特软信息的简化计算方法.该方法利用Gray码的对称性,通过递推求取比特软信息.分析和仿真结果表明,在高阶调制下,此方法较传统的ML和Max-Log计算方法,运算负担大大降低且对系统性能影响不大.此外,该方法可对不同调制阶数的PSK信号统一处理,适合应用于自适应编码调制系统.
This paper proposes a simplified bit metric calculation method for high-order PSK signal with Graymapping. This method calculates the bit metric recursively by the symmetry of Gray code. Analysis and simulation results show that the proposed method can significantly reduce the computational complexity and maintain similar performance compared to ML and Max-Log bit metric. Additionally, this method generates bit metrics of PSK signals with different modulation order in the same way, so it can be applied to adaptive modulation system.
出处
《中国科学:信息科学》
CSCD
2012年第6期663-673,共11页
Scientia Sinica(Informationis)
基金
国家自然科学基金(批准号:60801052)
航空科学基金(批准号:2009ZC52036)
南京航空航天大学基本科研业务费专项科研项目资助
关键词
相移键控
高阶调制
比特软信息
软解调
比特交织编码调制
phase shift keying, high order modulation, bit metric, soft demodulation, bit-interleaved coded modulation