In this paper, we study a joint spatial division multiplexing (JSDM) beamforming scheme which enables large-scale spatial multiplexing gains for massive MIMO downlink systems. In contrast to the conventional JSDM which employs a block diagonalization (BD) method as a pre-beamformer, we aim to maximize sum-rate by applying minimum-mean-squared error (MMSE) approaches when designing a pre-beamformer and a multi-user precoder sequentially. First, to suppress inter-group interference, we design the pre-beamformer which minimizes an upper bound of the sum mean-squared-error in the large-scale array regime. Then, to mitigate same-group interference, we present the multi-user precoder based on the weighted MMSE (WMMSE) optimization method, which requires the same channel state information overhead as the conventional JSDM. Through simulation results, we confirm that the proposed two-step beamforming method brings substantial performance gains in terms of sum-rate over the conventional JSDM schemes especially in low to medium signal-to-noise ratio (SNR) regime.
|Title of host publication
|2016 IEEE 27th Annual International Symposium on Personal, Indoor, and Mobile Radio Communications, PIMRC 2016
|Institute of Electrical and Electronics Engineers Inc.
|Published - 2016 Dec 21
|27th IEEE Annual International Symposium on Personal, Indoor, and Mobile Radio Communications, PIMRC 2016 - Valencia, Spain
Duration: 2016 Sept 4 → 2016 Sept 8
|IEEE International Symposium on Personal, Indoor and Mobile Radio Communications, PIMRC
|27th IEEE Annual International Symposium on Personal, Indoor, and Mobile Radio Communications, PIMRC 2016
|16/9/4 → 16/9/8
Bibliographical noteFunding Information:
This work was supported by the National Research Foundation of Korea (NRF) funded by the Korea Government (MSIP) under Grant 2014R1A2A1A10049769.
© 2016 IEEE.
ASJC Scopus subject areas
- Electrical and Electronic Engineering