高动态环境下高阶双二进制偏移载波信号的精确捕获

Accurate Acquisition of High Order Double Binary Offset Carrier Signals for High Dynamic Environment

针对高动态环境下双二进制偏移载波(DBOC)调制信号无法精确捕获的问题,该文提出一种基于部分匹配滤波结合快速傅里叶变换(PMF-FFT)的捕获方法。又针对捕获过程中相关损失和扇贝损失引起的检测性能降低问题,提出一种改进的捕获方法。该方法首先利用离散多项式相位变换(DPT)去除接收信号的高阶动态项,然后针对DBOC信号重新设计PMF-FFT算法;最后利用频谱校正法对FFT后的功率谱最大值进行校正。仿真结果表明,在同一条件下,该方法将检测概率提高了2 dB左右,并且有效缩短了捕获时间。

For the problem of without accurate acquisition of Double Binary Offset Carrier （DBOC） modulated sigual for high dynamic environment, a method which is based on Partial Matched Filtering （PMF） - Fast Fourier Transform （FFT） is proposed. According to the problem of low detection performance caused by the related loss and scallop loss, a new improved acquisition scheme is proposed. Firstly, the Discrete Polynomial phase Transform （DPT） is used to remove the high order dynamic term of the received signal, and then the PMF-FFT algorithm is redesigned for the DBOC signal. Finally, the spectrum correction method is used to correct the maximmn power spectrum after FFT. Simulation results show that, under the same conditions, the proposed scheme improves the detection probability by about 2 dB, and shortens effectively the acquisition time.