由匹配滤波器的讨论以及仿真分析可以得知，线性调频信号在经过传输时延以及加性噪声干扰的情况下，依然可以很有效的判断出信号的存在。-By matching the filter is discussed and the simulation analysis, linear FM signal after transmission delay and additive noise condition, still can be very effective to determine the pres