Kodlu devamlı faz modülasyonu taktik alıcı-vericileriçin

Satisfying the various demands of tactical transceivers is one the common challenges in military communications. Different modulation, coding and spread spectrum techniques are needed to meet these requirements. Although FSK is the most popular modulation technique used for tactical waveforms and frequently employed in military walkie-talkies, Continuous Phase Modulation (CPM) is superior to this conventional method due to its spectral efficiency feature. High spectral efficiency and constant envelope are the speci fications that make this modulation technique attractive for tactical waveforms. Serial concatenation of CPM with Low Density Parity Check Codes (LDPCs) provides a superior performance due to coding gains of this powerful code family. The choice of proper combination of LDPC and CPM is crucial to satisfy the targeted tactical waveform requirements of spectral efficiency, power efficiency and receiver complexity. In this thesis we address the problem of selecting the optimal transmission parameters in an LDPC-coded CPM system and investigating the performances under different jamming scenarios. The parameters are chosen to satisfy a given spectral efficiency subject to a constraint on the demodulator complexity. Speci cally, we consider modulation index, alphabet size, pulse shape duration and code rate as transmission parameters. Utilizing a systematic search procedure, we identify the proper transmission parameters to achieve a targeted spectral efficiency and error rate. Thereafter, the selected schemes are tested under attack of different frequency jamming signals.