Performance Analysis of 4×4 TDD-SVD-MIMO System in Suburban Field Trial

We investigated a 4×4 time division duplex (TDD) - singular value decomposition (SVD) - multiple-input multiple-output (MIMO) system that forms four eigenmodes and adaptively controls a bit allocation, a power allocation, and a channel coding rate to achieve a mobile transmission of 8K video for live productions that require high transmission rates and high link reliability. In this paper, we describe the proposed 4×4 TDD-SVD-MIMO technique and report the performance of a prototype system in a suburban field trial. We expanded the total number of allocated bits of SVD-MIMO up to 20 and demonstrated the 8K video transmission with the maximum data rate of 180 Mbps through a bandwidth of 18 MHz that corresponded to the spectral efficiency of 10 bit/s/Hz in actual mobile environments. We also investigated the effects of orthogonal- and single-polarization configurations. The results show that the utilization of orthogonal-polarization leads to higher eigenmode gains with the exception of the 1st eigenmode and higher data rates in the SVD-MIMO transmission than those in single-polarization.