Hybrid LS-LMMSE Channel Estimation Technique for LTE Downlink Systems
In this paper, the authors propose to improve the performance of the channel estimation for LTE Downlink systems under the effect of the channel length. As LTE Downlink system is a MIMO-OFDMA based system, a Cyclic Prefix (CP) is inserted at the beginning of each transmitted OFDM symbol in order to mitigate both Inter-Carrier Interference (ICI) and Inter-Symbol Interference (ISI). The inserted CP is usually equal to or longer than the channel length. However, the cyclic prefix can be shorter because of some unforeseen channel behaviour.