Research On The Key Technology Of Medium Wave Modem

Medium wave communication in our navy communication means of poverty, and foreignnaval vessels on the band application history can be traced back to the early application ofradio wave, modulation and demodulation technique is to make better use of medium waveband of the blank area, for the future of my modern military strategy to provide more diversemeans of communication.CPM (Continuous Phase Modulation) as the constant envelope and continuous phasemodulation signals, in contrast with other modulation techniques, has a very high bandwidthand power utilization rate. Due to constant envelope, continuous phase’s characteristics, whichdetermine its impact on characteristics of insensitive for the power amplifier of the nonlinearand the out-of-band radiation is smaller, which is leading the interference of small. In recentyears, CPM modulation and demodulation technology is developing rapidly, which in themobile communication, satellite communication, remote sensing and other fields have a widerange of applications.This paper is in combination with the Medium Wave communication channelenvironment, there is a comprehensive of detailed researches and analysis for the continuousphase modulation technology, first of all, the effects of performance parameters onContinuous Phase Modulation system were studied, this simulations show that under thecondition of different parameters, there is an different influence on performance. Secondly,combinewith the continuous phase modulation systems and convolutional codes, seriallyconcatenated continuous phase modulation system (SCCPM) is conducted with in-depthresearches, which have algorithm analysis and simulation of the SCCPM demodulationsystem based on Turbo,and it put forward a SISO of optimization algorithm on serialsystem.Then, based on the single index CPM (single-h CPM) system, deduce the multi indexCPM (Multi-h CPM) signal model, and makes the detailed description that proposed onekind based on the optimum detection of Viterbi algorithm and demodulation algorithm.Finally, the PAM pulse decomposition algorithm to reduce system complexity by Matlabsimulation for complex multi-index CPM system was proposed several methods to reduce thecomplexity of their systems.