一种跨导线性化低相噪压控振荡器

介绍了一种跨导线性化的宽带压控振荡器,由谐振腔电路、偏置电路、可编程电容阵列组成。提出一种通过电容隔直将有源器件进行交叉耦合的谐振腔结构,实现了有源器件的跨导线性化,大幅减小了有源器件自身的固有噪声,改善了压控振荡器的相位噪声特性。通过可编程电容阵列电路,可在压控振荡器内进行频率调节,扩展了振荡频率范围。测试结果表明,压控振荡器的振荡频率覆盖5 400~7 300 MHz,频率覆盖比达26%,在7 300 MHz时,相位噪声达到-128 dBc/Hz@1 MHz。该压控振荡器可作为高性能频率合成器的核心器件,构成本振信号源,可被广泛应用于无线基站、频谱监测等多种领域。

A Gm-Linearized Low-Phase-Noise VCO

A transconductance linearized wideband VCO was presented, which was composed of resonator circuit, bias circuit and programmable capacitor array circuit. Different from the direct cross-coupling structure of the grid drain electrode of the active device of the traditional VCO, an innovative resonant cavity structure with cross-coupling of the active device through capacitance isolation was proposed, which realized transconductance linearizationof the active device, and greatly reduced the inherent noise of the active device, so that the phase noise of VCO was improved. In the VCO, the frequency was adjusted through the programmable capacitor array circuit, which greatly extended the range of oscillation frequency. The test results showed that, the oscillation frequency covered 5 400~7 300 MHz, and the frequency coverage ratio of the VCO reached 26%. The phase noise reached -128 dBc/Hz@1 MHz at the oscillation frequency of 7 300 MHz. The VCO could be used as the core component of high performance frequency synthesizer, and could constitute the local oscillation signal source. It could be applied to wireless base station, spectrum monitoring and other fields.