caa a22 4500 606189939 CHVBK 20210128100852.0 cr unu---uuuuu 210128e20150301xx s 000 0 eng 10.1007/s10776-014-0257-5 doi (NATIONALLICENCE)springer-10.1007/s10776-014-0257-5 A Coherent PMI Estimation Scheme for Double Codebook [Elektronische Daten] [Dan Wang, Yong Liao, Yu Liu] The double codebook structures are proposed and applied in LTE-advanced, which can track both long-term and short-term channel state information. In traditional incoherent estimation, precoding matrix indicators (PMI) estimation is performed on each individual subcarrier and some form of averaging procedure then follows to combine the results from individual narrow-band processing. As a result, if there is a large deviation in any estimates of a subcarrier, it will lead to a larger deviation in the final result. Thus incoherent PMI estimation has a poor performance in low signal to noise ratio. This paper introduces a new PMI feedback scheme for wideband sources with coherent signal subspace method. This new technique estimates PMI based on an approximately coherent combination of each subcarrier by a focusing matrix. Simulation results show that the coherent estimation scheme has a better throughput performance than the traditional incoherent estimation. Springer Science+Business Media New York, 2014 PMI (precoding matrix indicators) nationallicence Double codebook nationallicence LTE-A nationallicence Wang Dan College of Communication Engineering, Chongqing University of Posts and Telecommunication, Chongqing, People's Republic of China aut Liao Yong Center of Communication and Tracking Telemetering Command, Chongqing University, Chongqing, People's Republic of China aut Liu Yu College of Communication Engineering, Chongqing University, Chongqing, People's Republic of China aut International Journal of Wireless Information Networks Springer US; http://www.springer-ny.com 22/1(2015-03-01), 67-72 1068-9605 22:1<67 2015 22 10776 https://doi.org/10.1007/s10776-014-0257-5 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s10776-014-0257-5 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Wang Dan College of Communication Engineering, Chongqing University of Posts and Telecommunication, Chongqing, People's Republic of China aut NATIONALLICENCE 700 1- Liao Yong Center of Communication and Tracking Telemetering Command, Chongqing University, Chongqing, People's Republic of China aut NATIONALLICENCE 700 1- Liu Yu College of Communication Engineering, Chongqing University, Chongqing, People's Republic of China aut NATIONALLICENCE 773 0- International Journal of Wireless Information Networks Springer US; http://www.springer-ny.com 22/1(2015-03-01), 67-72 1068-9605 22:1<67 2015 22 10776