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Channel Estimation Techniques in LTE for Downlink

Sinshaw Bekele, Dilip Mali


Multiuser and multi-antenna techniques are considered key to the latest mobile communication technology, which is termed as Long Term Evolution (LTE), to achieve peak user data rates. These techniques demand a precise measurement of the channel state. This study presents a review of channel estimation techniques put forward for LTE-downlink. Performance and implementation complexity of different pilot-assisted schemes such as Minimum Mean Square Error (MMSE), Least Square (LS) based channel estimation methods will be discussed in detail. Furthermore, semi-blind algorithms which make use of the data symbols in addition to the pilot tones are also presented.


Channel Estimation, LTE, MU-MIMO, LS, LMMSE

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