| 摘要 |
An oscillating signal generator for generating an oscillating signal having a variable oscillation frequency that can be near the unity gain frequency of the gain devices within the oscillating signal generator (Generation of High-Frequency Oscillating Signal Techniques, "GHOST"). Two gain stages, each with a respective effective resistance Reff, an emitter load capacitance CE, and a respective gain device having a unity gain frequency omega T, are cascaded and configured to provide a respective gain with a phase at substantially 180 DEG . In that case, the oscillation frequency, of the oscillating signal generated by the oscillating signal generator of the present invention, omega =[ omega T/(ReffCE)]+E,fra 1/2+EE . A feedback with a feedback gain is provided between the output to the input of the cascade of the two gain stages. The feedback gain is designed such that a product of the feedback gain and the gain through the cascade of the two gain stages is substantially one. The oscillation frequency of the oscillating signal generated by the oscillator can be varied by a corresponding variation to omega T and/or Reff. Alternatively, the oscillation frequency can be substantially fixed at a predetermined resonance frequency determined by a frequency determining network operatively connected to the cascade of the two gain stages. The oscillating signal generator of the present invention which can generate sine waves can be implemented with circuit elements that are easily fabricated on-chip within a monolithic integrated circuit. In addition, because oscillation frequencies near the unity gain frequency of the gain devices can be achieved, higher frequencies for a given power dissipation or lower power dissipation for a given frequency can be obtained.
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