| 摘要 |
<p>FREQUENCY SYNTHESIZER USING SPECTRUM SHIFT INTERPOLATION.. According to a particular embodiment of the present invention, a frequency synthesizer system is provided for producing a signal having a frequency which is variable in discrete steps over a predetermined frequency range. Each frequency step has a predetermined maximum size and means are provided for including interpolation frequencies between each step. The frequency synthesizer system comprises circuit means for combining a primary reference signal with a selected sub-harmonic of an externally generated interpolation signal frequency to produce a secondary reference signal frequency. A harmonic selection system generates harmonics of the secondary reference signal frequency and in response to a programming system selects a harmonic of the secondary reference signal having the same harmonic number as the selected sub-harmonic of the interpolation frequency. The harmonic selection system generates a control signal which controls the frequency of a controllable oscillator tuning and phaselocking the frequency of the controllable oscillator to a frequency equal to the frequency of the selected harmonic of the secondary reference signal frequency. Using the programming system the frequency of the controllable oscillator can be varied in steps, each having a maximum sizeequal to the primary reference frequency thereby generating a frequency which is displaced from the frequency of a harmonic of the primary reference signal by the interpolation frequency.</p> |
