TY - GEN
T1 - QRD-based antenna grouping for MIMO transmission
AU - Lin, Chun Tao
AU - Wu, Wen-Rong
PY - 2011/12/23
Y1 - 2011/12/23
N2 - The hybrid of spatial multiplexing and transmit beamforming is a simple scheme to combat channel fading in multiple-input multiple-output (MIMO) transmission. In this scheme, a set of transmit antennas is used to transmit a bit stream and antenna grouping is then required. How to conduct the grouping optimally is the main concern. For maximum-likelihood (ML) receivers, the grouping criterion is equivalent to maximizing the minimum distance of receive signal constellations, referred to as free distance. However, finding the free distance needs an exhaustive search which is not desirable. In the literature, a singular-value-decomposition (SVD) based method was proposed to obtain a lower bound of the free distance. Using the lower bound as the grouping criterion, one can solve the problem much easier. In this paper, we first propose using a QR decomposition (QRD) based method to obtain another lower bound. It can be shown that the lower bound yielded by the QRD is tighter than that by the SVD. We then propose using a basis-transformation method such that the QRD-based lower bound can be further tightened. Simulations show that the basis-transformed QRD-based method can yield near-optimum performance.
AB - The hybrid of spatial multiplexing and transmit beamforming is a simple scheme to combat channel fading in multiple-input multiple-output (MIMO) transmission. In this scheme, a set of transmit antennas is used to transmit a bit stream and antenna grouping is then required. How to conduct the grouping optimally is the main concern. For maximum-likelihood (ML) receivers, the grouping criterion is equivalent to maximizing the minimum distance of receive signal constellations, referred to as free distance. However, finding the free distance needs an exhaustive search which is not desirable. In the literature, a singular-value-decomposition (SVD) based method was proposed to obtain a lower bound of the free distance. Using the lower bound as the grouping criterion, one can solve the problem much easier. In this paper, we first propose using a QR decomposition (QRD) based method to obtain another lower bound. It can be shown that the lower bound yielded by the QRD is tighter than that by the SVD. We then propose using a basis-transformation method such that the QRD-based lower bound can be further tightened. Simulations show that the basis-transformed QRD-based method can yield near-optimum performance.
UR - http://www.scopus.com/inward/record.url?scp=83755219900&partnerID=8YFLogxK
U2 - 10.1109/VETECF.2011.6092862
DO - 10.1109/VETECF.2011.6092862
M3 - Conference contribution
AN - SCOPUS:83755219900
SN - 9781424483273
T3 - IEEE Vehicular Technology Conference
BT - 2011 IEEE Vehicular Technology Conference Fall, VTC Fall 2011 - Proceedings
T2 - IEEE 74th Vehicular Technology Conference, VTC Fall 2011
Y2 - 5 September 2011 through 8 September 2011
ER -