RCR Wireless
Kelly Hill
April 21, 2025
One of the defining characteristics of 5G networks has been the integration of massive multiple-input-multiple-output (MIMO) radios into the macro network, in order to increase spectral efficiency and provide faster throughput in spectrum from the midband on up.
MIMO systems have shifted from simple two-transmit, two-receive (2T2R) systems to an increasing number of elements. Signals Research Group recently took the opportunity after the close of 3GPP’s meeting in Seoul, South Korea, to do some comparative testing of MIMO systems in the form of 32T32R and 64T64R radios from Samsung Networks in Korea Telecom’s 5G Standalone network.
SRG wanted to know whether there were performance differences between the 64-element radio and a 32-element radio, and what any gains would look like. KT is in the process of migrating its 5G SA network from 32T32R to 64T64R radios, and its network in the Gangnam district of Seoul offered the chance to drive-test both radios in an apples-to-apples, urban scenario. Clearly the carrier sees the upgrade as investment-worthy—and the SRG testing shows why.
“We easily identified an obvious gain in downlink performance with the 64T64R radios,” SRG reported, going on to say that “there was a clear double-digit percentage gain with the use of more antenna elements.”
On an intriguing note, SRG also found that the relative performance gain for the 64T64R radios increased as network loading increased. The gains were “far more obvious during the midafternoon drive tests than the nighttime drive tests,” the benchmarking and analysis firm concluded.
“From an operator’s perspective, the performance gains translate into higher spectral efficiency, meaning the ability to support more voice and data traffic. This outcome was also very evident in the results we analyzed,” SRG said.
SRG also found that the relative gains increased with distances further away from the cell site.