A Monotonically Linear DCO for 77 GHz Automotive Radars

This paper presents a 77 GHz CMOS Monotonically Linear Digitally Controlled Oscillator (ML-DCO) that is derived from a Colpitts topology. A new tuning mechanism is developed that alleviates the need for an ideal switch and assures linearity. Large nonlinear varactors are avoided, and the MLDCO achieves 5 GHz linear tuning range that fulfills the requirements for short range and long range automotive radar sensors. Oscillating at 77GHz, the ML-DCO consumes a maximum of 9.12 mW and achieves a phase -noise of 98.53 dBc/Hz at a 1MHz offset frequency. The ML-DCO demonstrates 186 Figure of Merit and 182 Figure of Merit for Tuning.

本文介绍了一种基于科尔皮茨拓扑结构的77GHz CMOS单调线性数控振荡器（ML - DCO）。开发了一种新的调谐机制，它无需理想开关并确保了线性度。避免了使用大的非线性变容二极管，并且MLDCO实现了5GHz的线性调谐范围，满足了短程和远程汽车雷达传感器的要求。在77GHz振荡时，ML - DCO最大功耗为9.12mW，在1MHz偏移频率下实现了98.53dBc/Hz的相位噪声。ML - DCO的优值系数为186，调谐优值系数为182。