| 摘要 |
<p>PURPOSE:To measure the kinematic displacement of an object at a high accuracy by inserting a circuit for a Doppler signal varying in the phase at a high speed N times greater than the original signal in a displacement meter utilizing a 2-phase microwave Doppler sensor. CONSTITUTION:Two Doppler signals Ea and Eb varied in the phase by 90 deg. from each other with a wavelength of lambda are expressed by the equation. A circuit 7 determines a value Eac from the results with multipliers 8 and 9 and a subtractor 10 and the equations (1) and (2) using 2-phase carrier signals [cos2pif0t, sin2pif0t]. Then, the value Eac is multiplied N times with a multiplier circuit 14 to determine En. The value En is passed through a waveform shaping circuit 15 to make a sampling pulse. This sampling pulse is used to sample sine wave signals [cos(2piNf0t), sin(2piNf0t)] of a 2-phase oscillator 13 separately with sample hold circuits 16 and 17. Thus, the displacement DELTAR of the object is measured from revolutions (m) of new vectors [Ean, Ebn] from the relation DELTAR=mlambda/2N.</p> |
