A 77-GHz phased-array transceiver with on-chip antennas in silicon: transmitter and local LO-path phase shifting

Abstract—Integration of mm-wave multiple-antenna systems on silicon-based processes enables complex, low-cost systems for high-frequency communication and sensing applications. In this paper, the transmitter and LO-path phase-shifting sections of the first fully integrated 77-GHz phased-array transceiver are presented. The SiGe transceiver utilizes a local LO-path phase-shifting archi-tecture to achieve beam steering and includes four transmit and receive elements, along with the LO frequency generation and dis-tribution circuitry. The local LO-path phase-shifting scheme en-ables a robust distribution network that scales well with increasing frequency and/or number of elements while providing high-res-olution phase shifts. Each element of the heterodyne transmitter generates +12.5 dBm of output power at 77 GHz with a band-width of 2.5 GHz leading to a 4-element effective isotropic radi-ated power (EIRP) of 24.5 dBm. Each on-chip PA has a maximum saturated power of+17.5 dBm at 77 GHz. The phased-array per-formance is measured using an internal test option and achieves 12-dB peak-to-null ratio with two transmit and receive elements active. Index Terms—Integrated circuits, LO-path, mm-wave, multiple antenna, phase interpolation, phase rotator, phase shifters, phase