A 39 GHz MU-MIMO using 256 Element Hybrid AAS with Coherent Beam-Forming for 5G and Beyond IAB Applications

This paper describes the design and implementation of a 39GHz 256 element hybrid active phased array antenna system (AAS) which has the 16 individual digital transceivers, and its over-the-air (OTA) multi-user multiple-input multiple-output (MU-MIMO) verification. We have demonstrated the single carrier 1 GHz bandwidth 128 QAM transmission assuming the mobile-back-haul (MBH) link, and the OFDM 100 MHz bandwidth four users MU-MIMO using the zero-forcing (ZF) orthogonal multi-beams based on the channel reciprocity assuming the access links by using an AAS. The EIRP of 43 dBm in terms of 200 m link distance and the data rate of 5.5 Gbps with the 128 QAM in the single carrier operation, and the estimated total throughput of 1.59 Gbps according to 3GPP TS38.214 MCS table 2 in OFDM four (4) MU-MIMO have been achieved respectively. As per author's knowledge, this is a first demonstration assuming IAB applications using 39 GHz band.