Title :
Decision directed channel estimation for improving performance in LTE-A
Author :
Ketonen, Johanna ; Juntti, Markku ; Ylioinas, Jari
Author_Institution :
Centre for Wireless Commun., Univ. of Oulu, Oulu, Finland
Abstract :
The use of decision directed (DD) channel estimation in a MIMO-OFDM downlink receiver with a LTE pilot structure is studied in this paper. The space-alternating generalized expectation-maximization (SAGE) algorithm is used to improve the receiver performance from the one obtained by using the pilot symbol based least-squares (LS) channel estimator. The DD channel estimation improves the performance with high user velocities, where the pilot symbol density is not sufficient. The DD channel estimation can also be used to reduce the pilot overhead without any performance degradation by transmitting data instead of pilot symbols. The complexity of the SAGE channel estimator is discussed as well.
Keywords :
Long Term Evolution; MIMO communication; OFDM modulation; channel estimation; expectation-maximisation algorithm; least squares approximations; radio links; radio receivers; DD channel estimation; LTE pilot structure; LTE-A performance; MIMO-OFDM downlink receiver; SAGE algorithm; SAGE channel estimator; decision directed channel estimation; high user velocity; least-squares channel estimator; receiver performance; space-alternating generalized expectation-maximization algorithm; symbol density; Channel estimation; Complexity theory; Delay; OFDM; Throughput; Transmitting antennas;
Conference_Titel :
Signals, Systems and Computers (ASILOMAR), 2010 Conference Record of the Forty Fourth Asilomar Conference on
Conference_Location :
Pacific Grove, CA
Print_ISBN :
978-1-4244-9722-5
DOI :
10.1109/ACSSC.2010.5757787
