A Multi-Band 16-52-GHz Transmit Phased Array Employing 4 × 1 Beamforming IC With 14-15.4-dBm Psat for 5G NR FR2 Operation

• Published in: IEEE journal of solid-state circuits 2022-05, Vol.57 (5), p.1280-1290
• Main Authors: Alhamed, Abdulrahman, Gultepe, Gokhan, Rebeiz, Gabriel M.
• Format: Article
• Language: English
• Subjects: 5G mobile communication; Array signal processing; Beamformer; data link; error vector magnitude (EVM); fifth generation (5G); flip-chip; Gain; millimeter wave (mm-wave); multi-band; phased array; Phased arrays; printed circuit board (PCB); quadrature amplitude modulation (QAM); Radio frequency; SiGe; Silicon germanium; transmitter; Vivaldi antenna; Wideband
• ISSN: 0018-9200; 1558-173X
• DOI: 10.1109/JSSC.2021.3134325

This article introduces a millimeter-wave (mm-wave) multi-band transmit (Tx) phased-array design supp- orting the fifth-generation (5G) new radio frequency range 2 (NR FR2) bands. An eight-element phased-array module is presented employing two wideband 16-52 GHz 4{\times }1 Tx beamformer chips and tapered slot Vivaldi antenna array. The beamformer chips are designed in a SiGe BiCMOS process and flipped on a printed circuit board (PCB). The SiGe integrated circuit (IC) has four differential radio frequency (RF) beamforming channels each consisting of an active balun, analog adder-based phase shifter (PS), variable gain amplifier (VGA), and a two-stage class-AB power amplifier (PA). The RF input signal is distributed to the four channels using a compact Wilkinson network. The measured peak gain is 28.3 dB with 13.5-14.7 dBm output P_{1{\mathrm {dB}}} and 14-15.4 dBm P_{{\mathrm {sat}}} at 20-50 GHz. Each channel dissipates 250 mW from 2 V and 3-V supplies at P_{1\,{\mathrm{ dB}}} . The beamformer chip is tested using 64-QAM waveforms and achieves a data rate of 2.4 Gb/s at 5.2% rms EVM and 9.6-dBm average power. The eight-element phased-array module shows a broadband performance with excellent patterns and ±60° scanning capability and with a peak effective isotropic radiated power (EIRP) of 32-34 dBm at 19.5-51 GHz. At an EIRP of 21-22 dBm, 400-MHz 256-QAM 5G-NR compliant waveforms are transmitted with < 2.98% EVM demonstrating 5G NR FR2 operation. To the author's knowledge, this work achieves the highest bandwidth phased array with a peak EIRP of 34 dBm enabling the construction of multi-standard/multi-band 5G phased-array systems.