OFDM Channel Estimation Based on Pilot

We investigate channel estimation with LS (least square)and MMSE(minimum mean squared error) estimation criterion combined with OFDM multicarriers transmission′s property that the length of channel impulse response is shorter than the length of OFDM symbol. Blocktypeand combtype arrangement pilotbased channel estimation is considerd here.The channel is restored utilizing variant algorithms from the view of timedomain and frequencydomain . We simulate all the aigorithms and analysis their effect to system′s SER in OFDM system at last,The channel model is timevaring multipath Rayleighfading model under the WSSUS(Widesense stationary uncorrelated scatterring) assumption.The result showed that when the number of pilots is larger than the channel length scaled by system′s sample interval,Timedomain estimation is better than frequencydomain estimation,Otherwise MMSE estimation is better than LS estimation.