opEBPSK Based UNB Demodulation by Using Special Filters

UNB modulation, for its good performance, is paid to more attention. Special filter design is the key to UNB realization. Using opEBSK as UNB modulation scheme, the article presents a special design to realize opEBSK based UNB demodulation. The article first introduces optimized EBPSK modulation method and gives its time and frequency domain characteristics, and compared to that of EBPSK in the same time, opEBSK can lower the sideband level, while keeping the modulation information un-lost. Then, filter design is discussed, two zero and two pole digital filter is related, which shows narrower bandwidths and a fast response speed to the opEBPSK based UNB modulated signals, the filtered time domain waveforms are given. Although the filter bandwidth is much narrower, the modulation information still can be seen after passing them. Last, a system diagram is presented, simulation of UNB modulation and demodulation based on opEBPSK is done, experiments show that opEBPSK based UNB modulation has high bandwidth efficiency and good, even better BER performance.