摘要
针对直扩MSK信号的特殊性以及高动态环境下载波多普勒频偏对伪码捕获的影响,提出了一种直扩MSK信号的二维联合捕获方法。将直扩MSK信号构造成近似直扩BPSK的信号形式,在高动态环境下采用基于多普勒补偿-FFT的二维联合捕获算法对伪码相位和载波频率进行搜索,得到二者的估计值。最后通过MATLAB仿真得到了二维捕获的相关输出图形以及恒虚警条件下系统的检测概率和虚警概率随信噪比变化的曲线。仿真结果表明,由该方案设计的直扩MSK信号的捕获方法能够快速而准确地对伪码相位和载波多普勒频偏进行二维捕获。
In view of the special characteristics of the MSK signal and the influence of the Doppler frequency offset on the acquisition of PN code in highly dynamic environment, a two- dimensional joint acquisition method for MSK signal was proposed. Firstly,the DS- MSK signal was structured into an approximate expansion of DS- BPSK signal. Secondly, the two- dimensional acquisition al-gorithm based on the Doppler compensation and FFT was applied to search the pseudo code phase and carrier frequency and then get the estimation value of them. In the end, the graph of the result for the the two- dimensional acquisition algorithm and the curves of the detection probability and false alarm probability changing with SNR under the condition of constant false alarm were given. The result shows that the acquisition method designed according to the technology can complete the two- dimensional acquisition quickly and accurately.
出处
《电子技术应用》
北大核心
2016年第2期81-84,共4页
Application of Electronic Technique
