Abstract:

In the downlink transmission，LTE（long term evolution）system adopts OFDM technology，which modulates the highspeed data streams to N way orthogonal carriers. As a result，it is so vulnerable to the impact of frequency offset，especially in the Doppler frequency shift of high-speed environment，there will be a serious interference. In this paper，a special channel estimation process in LTE system is proposed for high-way environment. It is based on LS estimation，employing the methods of the CP-based frequency offset estimation and time domain energy concentration and other treatment to meet the high-speed mobile environment. Simulation results show that this method is more suitable for high-speed scenario compared with traditional methods，and as the speed reached 500 km/h，the error rate is still well-behaved.

Key words: LTE, channel estimation, high-speed railway, Doppler spread, down-sampled