Research On Channel Estimate Algorithm Based On The Pilot Carrier Frequency Of OFDM System

With the development of the mobile communication technology,the Orthogonal Frequency Division Multiplexing(OFDM) system has become the hotspot.It modulates the signals to sub-carriers which are orthogonal and increaseth e time for sending signals,while reduce the effect of inter-symbol interference(ISI) effectively. Channel estimation is one of the key technologies of OFDM system.Channel estimation algorithm just makes the mean square error(MSE) minimum,while obtains less complexity and the good pilot carrier performance.This article only discussed the channel estimate algorithm baed on the pilot carrier frequency.The typical algorithm estimated which based on the pilot carrier frequency includes:LS, LMMSE,DFT-based channel estimator and DC-T based channel estimator and so on. On the base of this,a DC-T based channel estimator for OFDM system is proposed. The proposed algorithm works in an iterative fashion.By exploiting the properties of DC,Tthis method mitigates the aliasing effect in the DFT-based channel estimator when the multi-path fading channels have non-sample-spaced path delays.This algorithm enables OFDM system to work well in mobile situations.From the Bit Error Ratio(BER) and mean square error(MSE),I compared the DC-T based channel estimator and the DFT-based channel estimator.The computer simulation results demonstrate effectiveness of the proposed DCT-based channel estimation method.