A 25-29 GHz 64-Element Dual-Polarized/Dual-Beam Small-Cell with 45 dBm 400 MHz 5GNR Operation and High Spectral Purity
This paper presents a 25-29 GHz 64-element small-cell dual-polarized/dual-beam phased-array for 5G communication systems. The small-cell includes dual-polarized antennas, sixteen 2x2 beamformers, a dual-channel driver, a dual-channel transceiver, filters, and a local oscillator on the PCB. This small-cell provides a measured EIRP_Psat of 55 dBm for each polarization with <-40 dBc LO leakage at an IF of > 4 GHz, and > 40 dB single-sideband rejection at an IF of 2-8 GHz. The TX output spectrum at an IF of 5 and 6 GHz is measured, and all the spurs are <-55 dB lower than the desired RF signal at 10-dB back-off operation. A complex modulation measurement using OFDM 5GNR 64-QAM 400 MHz waveform (PAPR = 11-12 dB) is performed and a 45 dBm EIRP is achieved at 5% EVM_RMS. To our knowledge, this is the first demonstration of a high-performance, low-spur phased-array for 25-29 GHz 5G systems.