Vehicle speed estimation method for array antenna assisted fast time-variation compensator in digital terrestrial television broadcasting receiver

摘要

OFDM (Orthogonal Frequency Division Multiplexing) is a multicarrier modulation technique capable of establishing wideband digital transmission over multipath environment and has been adopted in DTTB (Digital Terrestrial Television Broadcasting) systems. Although it is robust to the frequency selective fading due to multipath propagation it is vulnerable to the channel time-variation caused by Doppler spread. This weak point in OFDM causes the degradation of the reception quality in the mobile reception of DTTB. In this paper we propose a new array antenna assisted time-variation compensator with vehicle speed estimator. Computer simulation results show that the speed estimator can exactly estimate the vehicle speed And we conclude that the proposed compensator can considerably improve the bit error rate in the mobile reception of DTTB.