A Survey on Fft/ifft Processor for High Speed Wireless Communication System

The demand for increased channel capacity in mobile and wireless communication has been rapidly increasing due to multi fold increase in demands of multimedia services and mobile data. In the present scenario, high data rate are offered by WLAN, WiMax and LTE/ LTE-Advanced (LTE-A). Developing a wireless system for more spectral efficiency under varying channel condition is a key challenge to provide high bit rates with limited spectrum. MIMO system with OFDM gives higher gain by using the direct and the reflected signals, thus facilitating the transmission at high data rate. Efficient implementation of MIMO-OFDM communication system is based on IFFT/FFT algorithm. There is several variations in the FFT architecture, which are being used in MIMO-OFDM transceivers and are discussed in this paper. In this work, it is seen that the proposed mixed radix algorithm uses only less number of logic gates, adders and counters. It is been evident that FFT architecture can provide higher throughput rate with minimal hardware cost by adding the features of SDF and MDC pipelined architecture. Keyword: FFT/IFFT processor, MIMO-OFDM, SDF, MDC.