A 16-Element Phased-Array CMOS Transmitter with Variable Gain Controlled Linear Power Amplifier for 5G New Radio

This paper presents a 28-GHz 16-element phased-array transmitter for the fifth-generation (5G) new radio (NR) applications, focusing on the power amplifier (PA). The IC was fabricated using a 28-nm bulk CMOS technology with a flip-chip package, and evaluated with 5G NR signal having an 800-MHz total bandwidth. Each channel of the 16 phased-array transmitter has a 16 dBm output at 1-dB compression point and a large gain range from 24 to 63 dB. The full 16-element array achieves an average output power of 18 dBm with a record-level system error vector magnitude (EVM) of less than -33.5 dB (<2.1%) at a total power consumption of 1.63 W (102 mW of per channel) including all biases, digital control, and power-management-unit (PMU) blocks, over the frequency band from 26.5 to 29.5 GHz.