TY - GEN
T1 - Decoupled search for vector perturbation in multiuser downlink systems
AU - Park, Seok Hwan
AU - Han, Hyeon Seung
AU - Lee, Inkyu
PY - 2010
Y1 - 2010
N2 - In this paper, we propose a new vector perturbation scheme which reduces the complexity associated with finding perturbation vectors by searching for the real and imaginary components individually. To minimize a performance loss induced from decoupling joint search, we apply diagonal precoding at the transmitter whose phase angles are iteratively optimized according to the criterion of maximizing the chordal distance between subspaces spanned by the real and imaginary components. Since our main objective is to reduce the system cost, we also propose a simple non-iterative method of finding phase angles with slight performance loss. Simulation results show that the proposed decoupled vector perturbation reduces the average number of search candidate by 56% in comparison to the original vector perturbation in 4-by-4 system. It is also noted that the simple choice of phase angles provides the performance almost identical to that of the iteratively optimized angles. Moreover, we develope a receive antenna combining method for the vector perturbation systems with multiple-antenna receivers. The proposed algorithm designs receive combiners based on the criterion of optimizing the performance metric via a block-coordinate ascent approach.
AB - In this paper, we propose a new vector perturbation scheme which reduces the complexity associated with finding perturbation vectors by searching for the real and imaginary components individually. To minimize a performance loss induced from decoupling joint search, we apply diagonal precoding at the transmitter whose phase angles are iteratively optimized according to the criterion of maximizing the chordal distance between subspaces spanned by the real and imaginary components. Since our main objective is to reduce the system cost, we also propose a simple non-iterative method of finding phase angles with slight performance loss. Simulation results show that the proposed decoupled vector perturbation reduces the average number of search candidate by 56% in comparison to the original vector perturbation in 4-by-4 system. It is also noted that the simple choice of phase angles provides the performance almost identical to that of the iteratively optimized angles. Moreover, we develope a receive antenna combining method for the vector perturbation systems with multiple-antenna receivers. The proposed algorithm designs receive combiners based on the criterion of optimizing the performance metric via a block-coordinate ascent approach.
UR - http://www.scopus.com/inward/record.url?scp=77955362847&partnerID=8YFLogxK
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U2 - 10.1109/ICC.2010.5501933
DO - 10.1109/ICC.2010.5501933
M3 - Conference contribution
AN - SCOPUS:77955362847
SN - 9781424464043
T3 - IEEE International Conference on Communications
BT - 2010 IEEE International Conference on Communications, ICC 2010
T2 - 2010 IEEE International Conference on Communications, ICC 2010
Y2 - 23 May 2010 through 27 May 2010
ER -