This article presents a 230-GHz wideband harmonic voltage-controlled oscillator (VCO) with large output power based on a compact and low-loss structure of coupled standing wave oscillators. In order to boost the output power, oscillators are coupled together without adding extra passive loss to the circuit. Transistors with inductive drain impedances provide the necessary negative resistance to the oscillators while simultaneously acting as active variable capacitors for frequency tuning and generate the desired second-harmonic power through their nonlinearities. Transmission lines at the drains are responsible for creating the inductive impedance as well as coupling adjacent oscillators and routing and combining the output power. Therefore, the circuit has a compact structure that minimizes passive losses. A varactor-less frequency tuning scheme is used and allows for wideband operation without sacrificing the output power. In addition to oscillator coupling and minimizing the losses, the output power has been boosted by engineering the harmonic impedance that is seen by the transistors in the circuit. The prototype chip was implemented in a 65-nm CMOS process. The output power of the VCO covers 219–238 GHz frequency band (8.35% tuning range) and delivers 3.4-dBm maximum output power. The minimum measured phase noise is −105.8 dBc/Hz (at 10-MHz offset) while consuming 195 mW from a 1.5-V supply.

中文翻译：

---

65-nm CMOS 中的 230-GHz 高功率和宽带耦合驻波 VCO

本文基于紧凑、低损耗的耦合驻波振荡器结构，介绍了一种具有大输出功率的 230-GHz 宽带谐波压控振荡器 (VCO)。为了提高输出功率，将振荡器耦合在一起，而不会给电路增加额外的无源损耗。具有电感漏极阻抗的晶体管为振荡器提供必要的负电阻，同时充当用于频率调谐的有源可变电容器，并通过其非线性产生所需的二次谐波功率。漏极处的传输线负责创建电感阻抗以及耦合相邻振荡器和路由和组合输出功率。因此，该电路结构紧凑，可最大限度地减少无源损耗。使用无变容二极管频率调谐方案并允许在不牺牲输出功率的情况下进行宽带操作。除了振荡器耦合和最小化损耗之外，还通过设计电路中晶体管所看到的谐波阻抗来提高输出功率。原型芯片采用 65 纳米 CMOS 工艺实现。VCO 的输出功率涵盖 219–238 GHz 频段（8.35% 的调谐范围）并提供 3.4-dBm 的最大输出功率。测得的最小相位噪声为 −105.8 dBc/Hz（在 10 MHz 偏移时），同时从 1.5 V 电源消耗 195 mW。通过设计电路中晶体管看到的谐波阻抗，输出功率得到了提升。原型芯片采用 65 纳米 CMOS 工艺实现。VCO 的输出功率涵盖 219–238 GHz 频段（8.35% 的调谐范围）并提供 3.4-dBm 的最大输出功率。测得的最小相位噪声为 −105.8 dBc/Hz（在 10 MHz 偏移时），同时从 1.5 V 电源消耗 195 mW。通过设计电路中晶体管看到的谐波阻抗，输出功率得到了提升。原型芯片采用 65 纳米 CMOS 工艺实现。VCO 的输出功率涵盖 219–238 GHz 频段（8.35% 的调谐范围）并提供 3.4-dBm 的最大输出功率。测得的最小相位噪声为 −105.8 dBc/Hz（在 10 MHz 偏移时），同时从 1.5 V 电源消耗 195 mW。