Higher Order Differential Amplitude And Phase Shift Keying Modulation And Demodulation System And Simulation

This project study modulation arithmetic and demodulation arithmetic of multidifference amplitude and phase shift keying (MDAPSK). It is well known that QAMhas been used in many practical applications because it has high bandwidth efficiency.MDAPSK is combined by DASK and DPSK, non-coherent demodulation is adapted indemodulation module, the realization is easier than QAM, and the training sequence ofsymbol is not necessary. It can make the system transportation faster. The modulationand demodulation arithmetic is simulated in this paper, including MDPS29K,MDAPSKwith single carrier. MDAPSK modulation and demodulation with two carriers is alsosimulated in the paper. The relationship between SNR and EPR all modulation anddemodulation is depicted.The main contribution of this dissertation can be concluded as following.At first,difference phase shift keying is introduced,includingπ/4--DQPSK,8DPSK and 16DPSK. The relationship between EBR and SNR of 8DAPSK and16DAPSK is compared.Secondly, the modulation and demodulation theory and arithmetic of MDAPSK isstudied based on DPSK modulation and demodulation theory and arithmetic, the systemframework is designed according the theory and arithmetic. The modulation anddemodulation system of MDAPSK (M=16 32 64) is simulated in Matlab. 16DAPSK hastwo ways, one is 2DASP combine with 8DPSK, the other is 4DASK combine withπ/4--DQPSK. The relationship of SNR and BER is simulated and analyzed. Differenceof frequency according different M is studied.Thirdly, the simplified MDAPSK modulation and demodulation system isintroduced with 32DAPSK which is combined by 4DASK with 8DPSK based onMDAPSK modulation and demodulation. The two demodulation of 32DAPSK issimulated; they are the general 32DAPSK demodulation and the simplified 32DAPSKdemodulation, the adjudged valued can be algebraic average or geometrical average.The SNR performance of two 32DAPSK demodulation system is compared.At last, the modulation and demodulation system with two carriers is proposed to use in this paper, and the system is simulated in Matlab. The frame header can beused to realize synchronization; the identified codes are placed in modulate codes atevery carrier. The relationship of SNR and EBR is also simulated, and compare with thesingle carrier system.