Abstract
We have studied equalization techniques using pilot carriers for an OFDM system. The signal to interference ratios (SIRs) of the equalizer output signal over the time-invariant multipath channel (D/U=10dB) are calculated for several interpolation schemes : interpolation by FIR filters with the sinc functional impulse response, constant interpolation, linear interpolation and simplified liner interpolation (which can be realized without multipliers) schemes for the channel response estimation. The results show that the SIR of 26dB (input CNR=30dB, delay time of interference signal=11 μ S) are obtained for the simplified linear interpolation which can reduce the hardware complexity compared with other interpolation schemes. The SIRs are also calculated to the timing phase offset for the FFT window position in case of the FIR filters and the simplified linear interpolations. The results show that the degradation of SIR is very little even when the offset value becomes up to 20 samples for both cases.
