关键词：传感器；数字通信；数据通信系统；模拟波形
摘 要：In digital communications, either fixed, chaotic, or random, analog waveforms of finite duration are used to carry the information. To optimize a waveform communications system or determine its noise performance in analytic form, mathematical models of modulation and detection have to be developed. This chapter extends the conventional waveform communications concept to chaotic communications. A common property of chaotic modulation schemes, namely, the estimation problem that, if not prevented, corrupts the noise performance of chaotic communications systems, is discussed. Then, introducing the Fourier analyzer concept, a received signal space is defined in which every received signal either deterministic, chaotic, or random can be represented. Finally a step-by-step approach is given for the derivation of different detection algorithms. As examples, the derivations of coherent, averaged optimum noncoherent, and autocorrelation detection algorithms and detector configurations are shown. To show the feasibility of chaotic communications, an FM-DCSK data communications system operating in the 2.4-GHz ISM band is implemented. The FM-DCSK transceiver is implemented in software and a universal hardware device is used to convert the signals between the RF domain and baseband.