Abstract
This article introduces a millimeter-wave (mm-wave) multi-band transmit (Tx) phased-array design supporting 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 4x1 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 ${P_{1,{dB}}}$ and 14-15.4 dBm ${P_{ sat}}$ at 20-50 GHz. Each channel dissipates 250 mW from 2 V and 3-V supplies at ${P_{1,{ dB}}}$ . 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 degrees 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.