Electrical engineering

Physics

Channel (broadcasting)

CMOS

Insertion loss

Noise figure

Phase shift module

Optics

Engineering

Amplifier

Antenna (radio)

Computer science

Transmitter

Transceiver

Optoelectronics

Phased array

IEEE Transactions on Microwave Theory and Techniques

This article presents a power efficient 24-28-GHz four-element phased-array transceiver (TRX) front end (FE) for 5-G base stations and user equipment communications. A power efficient hybrid quadrature vector interpolation-based phase-shifting architecture is proposed to increase the TX and RX power efficiency and phase resolution. A transformer-based embedded T/R switch is proposed which minimizes TX and RX losses to ensure high TX output power and power efficiency while maintaining a low noise figure (NF) and extremely compact chip area. The 24-28-GHz four-element TRX FE is implemented in a 65-nm CMOS process (1P9M) for large-scale phased-array applications. The TX and RX paths achieve 0.8° phase resolution with <; 0.47°/0.17-dB RMS phase/gain error as well as 24-dB gain control range with 0.75-dB gain step and <; 0.1°/0.4-dB RMS gain/phase error over 24-30 GHz. The full TX path (including splitter and T/R switch) also achieves a measured 16.6-/18.9-dBm OP1dB/ P sat with 21.1%/16.6% PAE peak /OP1dB for each FE element while maintaining a minimum 4.4-dB NF in the full RX path (including combiner, T/R switch, and OFF-mode PA) at 28 GHz. Under the 64-/256-QAM modulation measurements, the full TX path achieves a state-of-the-art average output power of 13.5-/10.2-dBm per element (8.4%/3.5% full TX path PAE) with -26.4/-30.8 dB EVM and 27.8-/30.1-dB ACLR at 28 GHz, making the proposed TRX FE can be effectively deployed in both base stations and user equipment for 5-G communications. The chip size of the four-element TRX FE excluding I/O pads is only 3.4×1.1 mm 2 .

A 24–28-GHz Four-Element Phased-Array Transceiver Front End With 21.1%/16.6% Transmitter Peak/OP1dB PAE and Subdegree Phase Resolution Supporting 2.4 Gb/s in 256-QAM for 5-G Communications