An Integrated 16-Element Phased-Array Transmitter Front-End for Wireless Communication at 185 GHz

This paper presents a phased-array transmitter front-end for beamsteering wireless communication at 185 GHz with 16 elements in a 4×4 arrangement on a single chip. Integrated in a 130 nm SiGe BiCMOS process, the circuit includes a times-six frequency multiplier providing the LO signal for the mixer. The up-converted signal is divided and distributed to the 16 outputs with Wilkinson dividers, followed by 360-degree phase shifters at each output to provide beamsteering capability. With a total dc power consumption of 661 mW, the transmitter reaches -13 dBm of saturated output power for each element, or -1 dBm of combined power. Centered at 185 GHz, the -3 dB RF bandwidth is 30 GHz. The power-efficient design is consuming a dc power of only 41.3 mW per element. As a result, the presented circuit can be useful for low-power short-range wireless communication links with spatial diversity, for instance in board-to-board data transmission. To the authors' knowledge, this is the first demonstration of a 16-element transmitter front-end at carrier frequencies above 120 GHz.