摘要
提出了一种基于鉴相电流可实时调节特性的宽相对覆盖、低相位噪声的捷变频频率合成方法。该方法主要针对频合器在宽频率覆盖时会遇到环路带宽变化剧烈的问题,提出通过实时调节ADF4106的鉴相电流,对压控振荡器的等效压控增益非线性进行补偿,从而实现在宽覆盖范围内锁相环的环路带宽基本保持恒定。基于本方法研制实现了以ADF4106为核心的宽频率覆盖微波频合器;其全范围环路带宽基本恒定在600kHz,并具有良好的低相噪指标和捷变频性能。由于该方法显然也适用于其它具有程控鉴相电流功能的PLL专用芯片,故对于研制高性能频率合成器具有非常重要的现实意义。
A novel ADF4106 based technique to develop wide frequency-coverage frequency synthesizer with invariable loop bandwidth is proposed in this paper. With the proposed method, the nonlinear property of voltage controlled oscillator (VCO) is compensated by real-timely tuning the phase detector (PD) current of the ADF4106, so as to avoid the performance degradation due to acute variety of loop bandwidth in the case of wide frequency coverage. By this, a wide frequency-coverage microwave frequency synthesizer im- plemented is developed. Experimental results show that, this frequency synthesizer has the satisfied per- formances of stable loop bandwidth, low phase noise, and fast frequency-switching speed in the whole frequency coverage.
出处
《电子器件》
CAS
2008年第6期1871-1875,共5页
Chinese Journal of Electron Devices
关键词
频率合成器
宽覆盖
环路带宽
压控增益
鉴相增益
低相位噪声
frequency synthesizer
wide-band
loop bandwidth
VCO gain
phase detection gain
low phasenoise