1Supporting and Enabling Circuits for Antenna Arrays in Wireless Communications

Abstract—Antenna arrays have been demonstrated as a very promising technique for high-speed wireless network, and are anticipated to be indispensable components in future wireless communication systems. This review paper presents an overview of the circuit techniques on combining signals from different receive array elements as well as splitting signals to different transmit array elements with emphasis on silicon-based solutions. It also reviews circuit techniques to control the phase and the amplitude of signals from/to each array element such that signals from those array elements can be combined and split in a desired manner for achieving high data rate communications as well as interference management. Index Terms—Antenna array, RF (radio frequency) beamform-ing, LO (local oscillator) beamforming, baseband beamforming, digital beamforming, reflective-type phase shifter, load-line phase shifter, switched-delay phase shifter, Cartesian vector modulator, LO-path phase shifter, phase-oversampling vector modulator, wireless local area network (WLAN), millimeter-wave commu-nication, 60-GHz communication. I