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

Abstract

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 4 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">o</sup> , 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*5mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> area including pads.