IJF-OQPSK modulation schemes with MLSE receivers forportable/mobile communications

摘要

A receiver structure for constant enveloped IJF-OQPSK modulationnunder fading channel conditions is introduced. Its performance in AWGNnand Rayleigh fading channels was analyzed and verified by computernsimulations. Results show the relation between the performance of thensystem and the memory introduced by the double-interval overlappingnpulse shape. By properly using this memory, it is possible to achievensuperior performance compared to conventional schemes. Even though noncoding has been used, comparable results to coded schemes was obtainednwith no extra redundancy. Therefore, the complexity caused by multilevelnmodulation can be avoided, and transmission of signals with compactnspectrum and good performance is possible. The constant envelope,ncompact spectrum, superior performance in fading channels and lowncomplexity make the hardlimited IJF-OQPSK scheme a good choice fornportable/mobile communications, to achieve low cost, small size, andnhigh power and bandwidth efficiencies