Low-Noise 2-GHz-Band VCO Implementation for Frequency Synthesizers Used in Land Mobile Radio

So far, however, low noise VCOs which satisfy the severe requirements of mobile radio systems operating above 1 GHz have not been investigated. The design specifications are summarized, and it is shown that the VCO phase noise reduction requires a rigorous designed oscillator. Oscillator noise characteristics are reviewed, and design principles are clarified. In order to suppress the 1.f noise, a Claap oscillator circuit and a microstrip resonator are adopted. A Si BJT and GaAs MES FET are compared under optimum bias conditions