| 摘要 |
The system cancels transmitter to receive breakthrough. A laser transmitter (1) and a modulator (2), send towards a target a modulated transmission wave and reception means comprise a first mixer (24) for mixing a local wave from transmitter (1) with the wave reflected by the target, to produce a beat wave OB. A detector (9) furnishes the useful signal. Means (26) taps a fraction of said transmitted modulated wave, and modulators (7) and (8) modulate in phase and in amplitude said tapped wave to produce a correction optical wave OC. A second mixer (15), mixes said beat wave OB with the correction optical wave OC modulated in phase and in amplitude. A control circuit (10) for controlling said phase and amplitude modulation means (7 and 8) receives said useful signal so as to control said phase and amplitude modulation means (7 and 8) to eliminate the stray components that are superimposed on said beat wave, by minimising the amplitude of the useful wave SU. <IMAGE>
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