非周期长码直扩信号扩频码盲估计中的时窗划分准则

针对非周期长码直扩信号扩频码盲估计研究中缺乏时窗划分准则的问题，从时窗宽度和重叠宽度两个方面提出了时窗划分的基本准则。首先，通过分析时窗宽度、扩频比和扩频码周期对信息码跳变概率的影响，推导了时窗宽度、信息码跳变概率与误码率间的函数关系，从而确定了时窗宽度的选择依据；其次，以扩频码子段相位模糊的无误判决为原则，通过构造的相位模糊判决函数，推导出重叠宽度的选择依据。上述研究为扩频码子段的盲估计和相位模糊消除提供了理论支撑，进一步完善了非周期长码直扩信号的扩频码盲估计方法。

Time-window division criteria for blind estimation of NPLC-DS-SS signal spreading codes

There is a lack of exploration on the criteria for time-window partitioning in the blind estimation of spreading codes for non-periodic long-code direct sequence spread spectrum(NPLC-DS-SS) signals.In response to this problem,the basic principle of time-window division is proposed from two aspects,time window width and overlap width.Firstly,by analyzing the influence of the time window width,the spread spectrum ratio and the spreading code period on the information code jump probability,the function relation between the time window width,the information code jump probability and bit error rate(BER) is deduced,and the selection basis of the time window width is determined.Secondly,by using the unambiguous decision of the phase ambiguity of the spreading code subsegment as a criterion,the overlap width is derived through the phase fuzzy decision function.The time-window partitioning criteria established in above studies provides theoretical support for blind estimation and phase-blurring of the spreading code sub-segments,and further improve the blind-spectrum code blind estimation method for NPLC-DS-SS signals.