HHT AND DWT BASED MIMO-OFDM FOR VARIOUS MODULATION SCHEMES: A COMPARATIVE APPROACH

摘要

This paper presents a comparative study of HHT and DWT Based MIMO-OFDM for BPSK, QPSK and QAM modulation schemes in AWGN and Raleigh Fading Channel. Angular diversity is used in radars to mitigate the impairment caused by rapid fluctuations in Radar Cross Section (RCS) of the target. The antennas are placed in separate locations so that the target is seen from different angles. Such systems are called Statistical Multiple Input Multiple Output (MIMO) or MIMO radars with distributed antennas. This statistical MIMO radar exploits angular diversity to mitigate the impacts of RCS fluctuations. The channel capacity in AWGN channel is better when compared to the Rayleigh fading noise channel, since the SNR is high with low BER for any signal in any type of modulation technique. So that AWGN channel gives good results. Wavelet based OFDM has a lot of advantages compared to the FFT based OFDM. There is no need for cyclic prefix, flexibility and gives an optimal resolution. HHT based MIMO-OFDM gives better SNR and low BER compared to the FFT and DWT based MIMO-OFDM. In DWT MIMO OFDM, wavelets are applicable in almost all the areas of communications schemes with OFDM, which is a durable applicant for next peers of wireless schemes. Comparing different types of modulation schemes such as BPSK, QPSK and QAM, BPSK gives good results. So, finally HHT based MIMO OFDM In AWGN channel by using BPSK modulation technique gives better results compared to the DWT based MIMO OFDM.