针对传统延迟键控系统误码性能差的缺点，在频分复用的基础上，提出了一种新型的无信号内干扰多用户相关延迟键控通信系统.在所提出的系统中，发送端产生两路正交的混沌信号，并使用串并转换器在一个比特周期内发送多比特信息信号，再将两路正交混沌信号简单加、减法的线性组合以及调制的信息信号通过频分复用的方式实现传输.接收端将接收到的信号分别与对应混沌信号的组合进行相关解调，恢复出发送的多比特信息信号.推导了在Rayleigh衰落信道中系统的比特误码率公式并进行Monte Carlo仿真实验.理论分析及仿真结果均表明：随着用户数增加，系统的误码性能和传输速率得到提升，因此具有较好的实际应用价值.
In view of the defects of poor error performance in traditional correlation delay shift keying, a novel multi-user correlation delay shift keying with no intra-signal interference communication (NISI) system is proposed based on frequency division multiplexing (FDM). In the proposed system, the transmitter uses two branches those are orthogonal to each other and uses serial-parallel converter to transmit multi-bit information in one bit period, and it utilizes FDM to send the linear combination of simple addition and subtraction of two orthogonal chaotic signals and simultaneous information bearing signal. At the receiver, the received signals are noncoherent demodulation with the chaotic signals respectively to recover the multi-bit information signal. The bit error rate (BER) formula over Rayleigh fading channel is derived and Monte Carlo simulation experiments are worked. Theoretical analysis and simulation results show that with the increase of the number of users, the new scheme proposed in this paper can effectively improve BER performance and transmission rate, which indicates the good practical application feasibility.
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