A Frequency Synthesizer using Low Voltage Active Inductor VCO

저전압 능동 인덕터 VCO를 이용한 주파수 합성기

  • 이순재 (전북대학 전자정보공학부) ;
  • 이동건 (전북대학 전자정보공학부) ;
  • 정항근 (전북대학 전자정보공학부)
  • Published : 2010.02.01


This paper presents a frequency synthesizer using low voltage active inductor VCO(Voltage Controlled Oscillator). The low voltage active inductor VCO with feedback resistor increases its equivalent inductance and the quality-factor(Q). Under certain conditions, the low voltage active inductor with feedback resistor generates a negative resistance at the input. In this paper, the conditions for negative resistance are obtained by small signal analysis. The designed low voltage active inductor VCO covers a frequency band between 1059MHz and 1223MHz. The measured phase noise at 1.178GHz is -81.8dBc/Hz at 1MHz offset.


Frequency Synthesizer;Active Inductor;VCO


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