TY - JOUR
T1 - MIMO systems with limited rate differential feedback in slowly varying channels
AU - Kim, Taejoon
AU - Love, David J.
AU - Clerckx, Bruno
N1 - Funding Information:
This work was supported in part by Samsung Electronics, the National Science Foundation under grant CCF0513916, the SBC Foundation, and by the Doctoral Fellowship Program funded by the Korean Government (MOCIE). The materials in this paper have been presented in part at the IEEE Globecom Conference, December, 2008.
PY - 2011/4
Y1 - 2011/4
N2 - In this paper, an adaptive limited feedback linear precoding technique for temporally correlated multiple-input multiple-output (MIMO) channels is proposed, where the receiver has perfect channel knowledge but the transmitter only receives a quantized channel direction. To perform adaptation to the time correlation structure, we employ a differential feedback, where the "amount" of the perturbation added to the previous precoder is determined by the statistics of the directional variation. Based on random matrix quantization analysis, we develop a spherical cap codebook approach, where the cap is centered at the previous precoder and the radius of the cap is determined proportional to the identified directional variation. If the channel is highly correlated in time, it is shown that the proposed differential feedback scheme achieves significant throughput improvement in the large codebook size regime. The rest of the paper is devoted to developing a systematic spherical cap codebook generation method. The developed approach employs a feedback scheme that uses a differential rotation of the previously used precoder. Our codebook adaptation is based on generating a perturbation in Euclidean space and projecting the perturbation onto the unitary space. Simulation results show that the proposed adaptation scheme accurately tracks the channel using only a small rate of feedback.
AB - In this paper, an adaptive limited feedback linear precoding technique for temporally correlated multiple-input multiple-output (MIMO) channels is proposed, where the receiver has perfect channel knowledge but the transmitter only receives a quantized channel direction. To perform adaptation to the time correlation structure, we employ a differential feedback, where the "amount" of the perturbation added to the previous precoder is determined by the statistics of the directional variation. Based on random matrix quantization analysis, we develop a spherical cap codebook approach, where the cap is centered at the previous precoder and the radius of the cap is determined proportional to the identified directional variation. If the channel is highly correlated in time, it is shown that the proposed differential feedback scheme achieves significant throughput improvement in the large codebook size regime. The rest of the paper is devoted to developing a systematic spherical cap codebook generation method. The developed approach employs a feedback scheme that uses a differential rotation of the previously used precoder. Our codebook adaptation is based on generating a perturbation in Euclidean space and projecting the perturbation onto the unitary space. Simulation results show that the proposed adaptation scheme accurately tracks the channel using only a small rate of feedback.
KW - Multiple-input multiple-output (MIMO) channel
KW - adaptive linear precoding
KW - differential feedback
KW - limited feedback
KW - temporal correlation
UR - http://www.scopus.com/inward/record.url?scp=79955463718&partnerID=8YFLogxK
U2 - 10.1109/TCOMM.2011.022811.090744
DO - 10.1109/TCOMM.2011.022811.090744
M3 - Article
AN - SCOPUS:79955463718
VL - 59
SP - 1175
EP - 1189
JO - IEEE Transactions on Communications
JF - IEEE Transactions on Communications
SN - 0090-6778
IS - 4
M1 - 5723047
ER -