| 摘要 |
The invention relates to a frequency converter receiving an input signal and comprising means 1, 6, 5, 6' for producing a first local oscillator signal, a mixer 8 lowering the frequency of the input signal, means 10, 6, 14, 15 for producing a second local oscillator signal, another mixer 17 raising the frequency of the input signal with lowered frequency in order to provide the output signal. The said second means comprise a voltage-controlled oscillator 10 by means of which a control signal acts on the frequency of the second local oscillator signal and therefore on the frequency of the output signal so that the latter exhibits a Doppler type frequency shift. <IMAGE>
|
