Performance analysis of a pre-FFT equalizer design for DVB-T

Conventional OFDM employs a guard interval to combat delay spread distortion of transmitted data. This reduces the efficiency of the OFDM transmission. The combined OFDM-equalization strategy described here employs an adaptive equalizer to combat delay spread distortion and thereby facilitates the use of very short guard intervals and thus a more efficient OFDM modulation scheme. The OFDM receiver and the equalizer are described and performance is simulated for transmission in a multipath radio environment. It is shown that the combined OFDM-equalization method offers improved bandwidth efficiency over the conventional method but performance is sensitive to additive noise.