A W-Band Transmitter for Automotive Radar Sensors in 28-nm FD-SOI CMOS

Abstract

This article presents a 77-GHz transmitter (TX) in a 28-nm fully depleted silicon-on-insulator CMOS technology for automotive radar applications. The circuit has been designed to simultaneously fulfill both short-/medium-range (S/MR) and long-range (LR) operations. It exploits an LO frequency doubling architecture, which allows preventing voltage-controlled oscillator (VCO) pulling effects for improved phase noise (PN) performance. The proposed TX comprises a 38-GHz VCO driving a frequency doubler and then a current-combining two-path power amplifier. The VCO takes advantage of a novel tank architecture to cope S/MR and LR requirements with an effective and silicon area-saving solution. The proposed TX also features a feedback loop that allows properly setting the power delivered to the output load. It exhibits a 5-GHz bandwidth, ranging from 76 to 81 GHz, with a PN performance as low as −93 dBc/Hz at a 1-MHz offset frequency from a 77-GHz carrier. It is also able to deliver a maximum output power as high as 17.5 dBm with a dynamic control range of around 13 dB. The overall power consumption is 351 mW.

Interstacked Transformer Quad-Core VCOs

“…In this context, LC-resonant VCOs are highly preferred at the cost of a large silicon area consumption, mainly due to the tank inductor [3][4][5][6][7][8]. Traditionally, RF/mm-wave ICs are implemented in BiCMOS or CMOS technologies [9][10][11][12][13][14]. Despite several advantages of BiCMOS over CMOS in terms of noise (i.e., lower flicker noise corners), thicker back-end-of-line (BEOL) [15], higher transistor breakdown voltage (BV), and lower transconductance, g m , at a given current level, CMOS is becoming the reference process since it is highly suitable for system-on-chip (SoC) integration, which is pursued by microelectronic industries to reduce chip cost, power consumption, and area occupation [16,17].…”