PERFORMANCE ANALYSIS OF SINGLE CARRIER-FREQUENCY DOMAIN EQUALIZATION OVER ORTHOGONAL FREQUENCY DIVISION MULTIPLEXING USING MATLAB

The driving force in today's wireless market is the excellent internet services and growing demand for wireless multimedia. OFDM has been widely accepted as a solution for high-speed broadband applications. In this paper, we have attempted to present a comprehensive overview of a promising alternative solution, SC-FDE, which has been historically shadowed by OFDM. Although the basic ideas behind SC-FDE can be traced back to Walzman and Schwartz's work on adaptive equalizers in 1973, the recent surge of interest in SC-FDE was subsequent to the work of Sari. SC-FDE enjoys a comparable complexity to OFDM due to the similar transceiver architecture based on efficient FFT/IFFT operations. Because of the single-carrier implementation, SC-FDE also avoids the inherent drawbacks of OFDM such as amplifier nonlinearities, carrier frequency offsets, and phase noise. OFDM is commonly used in practice in conjunction with coding. The comparative performance analysis of SC-FDE, coded OFDM, and adaptive OFDM schemes reveals that SC-FDE achieves comparable (or even better in some scenarios) performance compared to its OFDM counterpart. this paper has compared the two schemes SC-FDE and OFDM, especially the BER performance of OFDM & SC-FDE Zero forcing, SC-FDE(MMSE). Both schemes involve frequency-domain processing, and their complexity is similar, in BER curve for ZF and OFDM is OFDM performs better than SC-FDE with zero forcing equalizer. The Zero forcing equalizer runs almost parallel to OFDM BER curve though above it. The reason being whenever there are deep fades in the channel noise gets amplified and results in degradation of the performance & in the BER curve for MMSE equalizer shows better performance compared to OFDM beyond certain Signal to Noise ratio. Unlike ZF equalizer, MMSE coefficients takes into account the effect of channel noise. Also this equalizer can potentially exploit the full diversity available in the channel