Zhilin Chen

A Ku band 4-Element phased array transceiver in 180 nm CMOS

A Ku Band (15∼18 GHz) 4-Element (4 Transmitters/4 Receivers) fully differential phased array transceiver is designed and fabricated using a 180nm CMOS process. The proposed phased array integrated with T/R switches and SPI controller is based on an all-RF structure. TX and RX channels are placed side-by-side to improve integration density and isolation. Each channel consists of a 5-bit phase shifter and a 4-bit attenuator. The measured maximum gain is 21 dB for a TX channel and 10.8 dB for a RX channel. The minimum noise figure of RX with T/R switch is 9.9 dB. The input referred PidB of RX is −14.5 dBm at 16GHz, while the output referred PidB of transmitter is 10 dBm at 16 GHz. Additionally, the RMS phase error of phase shifter is less than 4o, and the RMS amplitude error of attenuator is less than 3.2 dB. A RX element draws 114 mA from a 1.8 V supply, while a TX element consumes 145 mA with a 3.3V supply. The chip occupies 4.5∗5mm2 area including pads.

A 39 GHz broadband high-isolation CMOS mixer using magnetic-coupling CG Gm stage for 5G applications

This paper presents a 39 GHz broadband high-isolation mixer for 5G applications in 65 nm CMOS process. By adopting a common-gate (CG) gm stage with magnetic coupling, the mixer obtains a wide RF bandwidth without extra input matching components, which is benefit for system-level design. Meanwhile, it can improve gain and noise performance. Besides, a fully symmetrical design method is employed to keep a minimum LO leakage. According to experimental results, the mixer operates from 27.6 to 57.8 GHz and achieves a gain of 7.3 dB under LO power of 0 dBm. The LO-RF and LO-IF isolations are 59.5 and 57 dB, respectively.