TY - GEN

T1 - Pilot power ratio for uplink sum-rate maximization in zero-forcing based MU-MIMO systems with large number of antennas

AU - Min, Kyungsik

AU - Jung, Minchae

AU - Kim, Taehyung

AU - Kim, Younsun

AU - Lee, Juho

AU - Choi, Sooyong

PY - 2013

Y1 - 2013

N2 - This paper analyzes the pilot power ratio (PPR) in multiuser multiple-input multiple-output (MU-MIMO) systems with a large number of receive antennas (M) at the base station (BS). We consider zero-forcing based MU-MIMO orthogonal frequency division multiplexing (OFDM) systems. Based on the deterministic uplink sum-rate approximation for imperfect channel state information, we can formulate the optimization problems in terms of the PPR to maximize the ergodic uplink sum-rate subject to the per-slot or per-symbol power constraint. Under the per-slot power constraint, the optimal PPR can be obtained in a closed form while under the per-symbol power constraint, we propose an iterative algorithm which generates a suboptimal PPR. Simulation results show that the proposed PPRs perform close to the optimal performance in terms of the sum-rate. Also, it is shown that the proposed PPRs outperform the equal power allocation. In particular, in the ZF-R based MU-MIMO OFDM system with 8 users and M = 32 under the per-slot power constraint, the proposed PPR can achieve about 8bps/Hz performance gain compared to the equal power allocation.

AB - This paper analyzes the pilot power ratio (PPR) in multiuser multiple-input multiple-output (MU-MIMO) systems with a large number of receive antennas (M) at the base station (BS). We consider zero-forcing based MU-MIMO orthogonal frequency division multiplexing (OFDM) systems. Based on the deterministic uplink sum-rate approximation for imperfect channel state information, we can formulate the optimization problems in terms of the PPR to maximize the ergodic uplink sum-rate subject to the per-slot or per-symbol power constraint. Under the per-slot power constraint, the optimal PPR can be obtained in a closed form while under the per-symbol power constraint, we propose an iterative algorithm which generates a suboptimal PPR. Simulation results show that the proposed PPRs perform close to the optimal performance in terms of the sum-rate. Also, it is shown that the proposed PPRs outperform the equal power allocation. In particular, in the ZF-R based MU-MIMO OFDM system with 8 users and M = 32 under the per-slot power constraint, the proposed PPR can achieve about 8bps/Hz performance gain compared to the equal power allocation.

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U2 - 10.1109/VTCFall.2013.6692364

DO - 10.1109/VTCFall.2013.6692364

M3 - Conference contribution

AN - SCOPUS:84893338647

SN - 9781467361873

T3 - IEEE Vehicular Technology Conference

BT - 2013 IEEE 78th Vehicular Technology Conference, VTC Fall 2013

T2 - 2013 IEEE 78th Vehicular Technology Conference, VTC Fall 2013

Y2 - 2 September 2013 through 5 September 2013

ER -