Based On Software Radio Digital Shortwave Receiver Research Regularly

With the rapid development of science and technology, the high precision time isincreasingly important in our life. The short-wave timing, as one of the major timetransfer means in China, is always playing an important role in national defense andnational production. A short-wave receiver, which is the key in whole system, isreceiving signal device in short-wave time transfer system. Its performance affectstiming precision directly.A design of digital short wave receiver with Software Defined Radio (SDR) ispresented in this thesis. First of all, it is introduced how a short-wave receiver workesand what the broadcasting format of BPM short wave timing signal is. Secondly, thetheoretical basis of digital short-wave receiver with SDR are researched, which consistsof sampling theory, quadrature demodulation, filter design, signal demodulate algorithmand synchronous mode. Thirdly, according to the analog shortwave receiver workingprinciple, the mathematical model of digital shortwave timing receiver is established.Then, based on this mathematical model, the design schemes of a single andmulti-channel shortwave receiver are presented, various filters, which are used thedigital short-wave timing receiver, are designed and Signal digital demodulationsoftware is developed with VHDL language, DSP assembly language and MATLABsoftware. At last, the proposed scheme are tested, and the results indicate that theperformance of this receiver clearly superior to the property of analog timing receiver.