基于Dual-Mode MMA+MDD 双模式T/2分数间隔盲均衡算法的研究

均衡技术是用来解决通信系统中码间干扰的常用方法.针对传统恒模算法的收敛速度和稳态剩余码间干扰大的缺点,将双模式多模算法和改进型判决引导算法结合起来,并且应用于分数间隔盲均衡器中.该算法初期用双模式算法收敛均衡器,然后切换到改进型判决引导算法中进一步收敛,由于分数间隔均衡器解决了波特间隔均衡器因抽样率不高带来的频谱混叠问题,从而进一步地提高了均衡效果.蒙特卡罗仿真表明,该算法不仅收敛速度快,而且得到较低的剩余码间干扰.

Research of Dual-Mode MMA+MDD Dual Mode based on T/2 fractionally-spaced equalization

Equalization technique is an usual way to solve the inter-symbol interference problem in communication system.The dual-mode modified multi-mode algorithm and modified decision directed algorithm were combined in the fractionally-spaced equalizer to improve the performance about convergence speed and steady residual inter-symbol interference which produced by traditional constant modulus algorithm.The dual-mode was used to adjust equalizer,and the equalizer was further adjusted by switching to decision directed algorithm.And fractionally-spaced equalizer solves the spectrum aliasing problem,caused by baund-spaced equalizer because the sampling rate is not high,thus the performance of equalizer was further improved.Monte Carlo simulation shows that the algorithm has fast convergence with lower residual ISI.