In a quantization based multiuser multipleinput/ multiple-output (MU-MIMO) broadcast channel, the effective channel gain (i.e., the norm of a channel vector obtained from the receive combiner) needs to be considered in addition to a reduction of quantization errors for maximizing the signal-tointerference plus noise ratio (SINR). In this work, we prove that the effective channel gains in the space limited by an N R × M T MIMO channel form a min(M T, N R)-dimensional ellipsoid in the channel space. Utilizing the geometric proof, the achievable effective channel gain is derived as a function of its direction for a given MIMO channel. Based on the derivation, we finally propose a quantization vector selection criterion and an optimal receive combiner to maximize the SINR. The proposed maximum SINR based combining (MSC) is proven to be a better solution for maximizing the SINR compared to quantization based combining (QBC) and maximum gain based combining (MGC), each of which attempts to minimize quantization errors and maximize the effective channel gain.
Bibliographical noteFunding Information:
This research was supported by the MKE (The Ministry of Knowledge Economy), Korea, under the ITRC (Information Technology Research Center) support program supervised by the NIPA (National IT Industry Promotion Agency) (NIPA-2011-C1090-1101-0006).
This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (2010-0011995).
All Science Journal Classification (ASJC) codes
- Electrical and Electronic Engineering