A Low-Complexity Adaptive Transmission Scheme Based on the Dual-Codebook of 3GPP LTE-Advanced
In order to meet the peak spectral ef.ciency requirements of up to 30 bit/s/Hz, LTE-Advanced supports up to eight transmit antennas in its downlink, for which a dualcodebook is agreed for precoding. In the dual-codebook approach, the precoding matrix to be used is obtained via the multiplication of two precoding matrices W1 and W2 selected from each of the dual-codebook. For adaptive precoding under this con.guration, user equipment (UE) is required to include in its feedback information the precoding matrix indicators (PMIs) corresponding to both W1 and W2. In this paper, we propose a low-complexity precoding select method to select W1 and W2 separately, considering the the dual-codebook functionality. In the proposed scheme, a W1 for every possible rank will be chosen .rstly according to the principal directions of the long-term channel and thereafter an appropriate rank and W2 are sought to maximize the sum minimum mean square error (MMSE) rate. Besides, UE will feed back a channel quality indicator (CQI) for each codeword to signal the supported adaptive modulation and coding scheme to achieve a target codeword error ratio (CWER). Simulation results show that the proposed scheme has a comparable performance with the general extensive joint select method but with a substantially reduced complexity due to the signi.cantly reduced number of channel inversions.
MIMO LTE-Advanced Link Adaption Dual-Codebook Precoding.
Minxia Hu Shi Jin Xiqi Gao
National Mobile Communications Research Laboratory, Southeast University Nanjing 210096, China
国际会议
南京
英文
1-5
2011-11-09（万方平台首次上网日期，不代表论文的发表时间）