一种M进制短参考置换索引的差分混沌移位键控系统

Differential Chaos Shift Keying System with M-ary Short Reference Permutation Index

摘要:

为解决置换索引的差分混沌移位键控(PI-DCSK)通信系统存在能量效率低的问题,结合短参考技术,提出了一种M进制短参考置换索引的差分混沌移位键控(SR-PI-DCSK)系统。该系统将参考时隙的混沌序列缩短至小于半个符号周期,信息时隙将参考时隙的置换排列副本进行复制并拼接P次,在不增加PI-DCSK系统结构复杂度及维持相同的恢复比特信息所需能量的情况下,可以有效提高系统能量效率,同时提升系统的误比特率(BER)。然后,分析了SR-PI-DCSK 系统的能量效率,推导了其在多径瑞利衰落信道环境下的BER表达式,使用蒙特-卡罗模拟仿真验证了该理论推导的正确性。仿真结果表明,在同一条件下,所提出的系统与PI-DCSK系统相比具有更好的性能增益,这能为下一代物联网短距离通信应用提供一种混沌调制方案。

Abstract:

To solve the problem of the low energy efficiency of permutation index differential chaos shift keying (PI-DCSK) communication systems that employ short-reference technology, we developed an M-ary short-reference PI-DCSK (SR-PI-DCSK) system. We shortened the chaotic sequence of the reference time slot to less than half of a symbol period and confirmed that the information time slot copied and spliced the permutation arrangement of the reference time slot P times. We analyzed the energy efficiency of the SR-PI-DCSK system and derived its BER expression in a multipath Rayleigh fading channel. Further, we verified the accuracy of the theoretical derivation using Monte Carlo simulations. The simulation results indicate that compared with the PI-DCSK system, the proposed system has a better performance gain under the same conditions, thus providing a candidate chaotic modulation scheme for the next generation of short-range communication applications in the Internet of Things (IOT). Moreover, the system can effectively improve the energy efficiency and bit error rate (BER) of the PI-DCSK system without increasing its structural complexity while requiring the same energy to recover the bit information.