基于正交解扩的信干比估计方法

研究了TDD-CDMA(时分双工-码分多址)系统中的SIR(信干比)估计问题。现有的SIR估计方法准确度依赖于信道条件和观测时间,而TDD-CDMA系统复用时隙短,车速条件下信道变化剧烈的特点使得估计准确度降低。针对这种情况,提出了一种基于正交解扩的SIR估计方法。通过COSSAP仿真对比结果表明,该方法在瑞利衰落信道和AWGN(加性高斯白噪声)信道条件不同调制方式下,从低SIR到高SIR的很大范围内都有比较好的性能。

An SIR Estimation Technique Based on Orthogonal Despreading

This paper studies the signal-to-interference-ratio(SIR) estimation in Time Divided Duplex-Code Division Multiple Access(TDD-CDMA) communication system.The precision of the existing SIR estimation techniques depends on channel condition and observation window.But in the TDD-CDMA system,the specific condition that the time slot multiplexed is short and channel condition varies sharply for different vehicle speed makes the accuracy of estimation decrease.In this paper an SIR estimation technique based on orthogonal despreading is proposed to solve this problem to some extent.The results of the simulated comparisons through COSSAP show that both in Rayleigh fading channel and in AWGN channel,with different constellation modulation method,the proposed SIR Estimation technique can perform well even at low SIR.