一种新型低相位噪声低功耗Colpitts QVCO设计

Design of a New Low-Phase-Noise Low-Power Colpitts QVCO

设计了一种新型的低相位噪声低功耗Colpitts正交压控振荡器（QVCO）。此QVCO采用电流开关技术降低相位噪声,采用跨导增强技术改善核心电路的起振条件,并基于器件重用技术实现电路的反向注入锁定。提出的Colpitts QVCO比交叉耦合LC VCO的相位噪声更低,并且比传统QVCO的相位噪声、正交相位精度以及调谐范围的性能更优。最终基于0.18μm CMOS工艺流片实现的Colpitts QVCO在1.5 V工作电压下,功耗为0.9 m W,振荡频率为4.8-5.6 GHz,调谐范围高达15.4%,在中心振荡频率5.2 GHz处的相位噪声为-115.8 d Bc/Hz@1 MHz,正交相位误差为0.3°,此QVCO的芯片面积为0.5 mm×1 mm。

A novel low-phase-noise low-power Colpitts quadrature voltage-controlled oscillator （QV- CO） was designed. For the QVCD the current switching technique was adopted to reduce the phase noise and the transconduetance enhancement technique was adopted to improve the startup condition in the os- cillator core. Based on the devices reuse technique, the anti-phase injection locking for QVCO was rea- lized. The proposed Colpitts Qvco has superior phase noise than the cross-coupled LC VCO and outper- forms the conventional QVCO in phase noise, quadrature phase accuracy and tuning range. Based on the 0. 18 μm CMOS, the Colpitts QVCO consumes a power of 0.9 mW at a 1.5 V power supply, and exhi- bits a phase noise of -115.8 dBc/Hz at 1 MHz offset, an oscillation frequency of 4.8-5.6 GHz, a tu- ning range of 15.4%, and a quadrature phase error of 0.3° at the center frequency of 5.2 GHz. The chip area of the QVCO is 0.5 mm×1 mm.