The novel decision feedback equalizer for OFDM system with insufficient cyclic prefix

If the multipath delay difference is greater than the duration of a cyclic prefix, the performance of an orthogonal frequency division multiplexing (OFDM) system suffers severe degradation. The insufficient cyclic prefix phenomenon incurs two adverse interferences, intersymbol interference (ISI) from the adjacent symbols and intercarrier interference (ICI) from other subcarriers in the same OFDM symbol interval. We propose a novel decision feedback equalizer (DFE) receiver to improve the performance of an OFDM system with insufficient cyclic prefix. The proposed receiver does not require knowledge of the channel impulse response. Simulation results confirm the advantages of our proposed receiver over the TEQ technique.