Abstract: Chirp modem is a reliable and robust data transferring tool which is a combination of Chirp signal and digital modulate mode. However, the received Chirp signal always contains voice noise transmitted by broadcasting station in engineering practice of communication which severely restricts the application of Chirp signal. Due to the non-smooth character of voice noise, tradtional denoising method hardly works. This paper puts forward a voise noise denoising algorithm which is available to Chirp signal. This algorithm is applied to process the received Chirp-BPSK signal. The power of the voice noise on received signal is cut down. Resultingly, the performance of the communication system is improved. The results show that the algorithm has a good performance.

Key words: Chirp signal, voice noise, non-smooth, linear predictive coding, denoising

摘要： 采用Chirp信号为载波与各种数字调制方式相结合的Chirp调制信号作为一种数传工具，具有很强的可靠性和鲁棒性。然而接收机上的Chirp接收信号常常伴有周边广播电台发射出的语音噪声干扰。随着广播电台的发展，语音噪声的能量有逐渐变强的趋势，严重影响Chirp信号传输的可靠性和有效性。由于语音噪声的非平稳性，传统的消噪方法难以取得较好的效果。提出一种适用于Chirp信号的语音消噪算法，对短波接收机上的Chirp-BPSK信号进行消噪处理。接收信号上的加性语音噪声被大幅度削减，系统的误码率性能得到很大提升，验证了该消噪算法的有效性。

关键词: Chirp信号, 语音噪声, 非平稳性, 线性预测, 消噪