摘要
主要是解决数字接收机中，对多路QPSK信号解调时所存在的较大载波频差的难题。采用理论研究分析和仿真验证相结合的方法，提出了一种将对大频差的直接估计转换成对一个已知序列的周期估计的新算法．该算法可以将实际解调中存在的用现有算法较难解决的大频差问题用一个较为简单的算法进行有效的估计和矫正，解决了数字化解调中的一个难题。研究认为，所提算法具有简单、计算量成小、统计特性好等特点，特别适用于多路QPSK信号的数字化解调。仿真结果表明该算法是可行的，目前已在实际系统中得到应用。
Abstract: Digitized demodulation of multi-channel QPSK signals often can not proceed normally due to the occurrence of unacceptably large frequency-offset. We now present an algorithm for estimating large frequency-offset and rectifying it to make it acceptably small. Section 1 gives the mathematics underlying our algorithm. Section 2 discusses in much detail the estimation of large frequency-offset and the proposed rectification to make it acceptably small. We like to point out that eqs. (11) and (12) are particularly important. Simulation results, as given in Tables 1 and 2, show preliminarily that our algorithm is feasible. Moreover, our algorithm functioned smoothly when it was employed in an actual system for digitized demodulation of 32-channel FDMA/QPSK signals implemented on TMS320C6X.
出处
《西北工业大学学报》
EI
CAS
CSCD
北大核心
2002年第1期87-90,共4页
Journal of Northwestern Polytechnical University
基金
国家自然科学基金(69872027)资助
