无信号内干扰的降噪多用户CDSK混沌通信系统

Chaotic communication system of noise reduction multiuser correlation delay shift keying with no intra-signal interference

针对传统的相关延迟键控(correlation delay shift keying,CDSK)方案误码率(bit error rate,BER)高的缺点,提出一种无信号内干扰的降噪多用户CDSK(noise reduction multiple-user CDSK)混沌通信系统。在发送端,参考信号长度为R的混沌序列复制P次所得,之后分为两路,利用Walsh码序列的正交性,使得每路中参考信号与N个信息信号之间彼此正交,并结合正交调制进一步提升数据传输速率。在接收端,接收信号利用滑动平均滤波器降低噪声方差,并进行相关解调。对该系统在加性高斯白噪声(additive white Gaussian noise,AWGN)信道和两径Rayleigh衰落信道中进行了BER公式推导与仿真分析,结果显示该系统能够有效地提升BER性能与数据传输速率。

Because of the disadvantages of traditional chaotic communication system correlation delay shift keying(CDSK)scheme which has high bit error rate(BER),a chaotic communication system of noise reduction multiple-user CDSK system with no intra-signal interference is proposed.At the transmitter,the reference signal is obtained by duplicating P times of R-long chaotic sequence,and then divided into two channels.The orthogonality of Walsh code is used to make the reference signal and the information signal in each channel orthogonal to each other and the data transmission rate is further improved by combining with orthogonal modulation.At the receiver,the received signal is processed with a moving average filter to reduce the noise variance and the correlation is demodulated.The BER formula is derived and simulated about the system in additive white Gaussian noise(AWGN)channel and two-path Rayleigh fading channel.The results show that this system can effectively improve the BER performance and data transmission rate.