From 1964 to 1972, at the early stages of the laser guns to carry out, most of the optical device is simpler, with various components assembling and optical performance and power is not high, use the alignment is not convenient.Various forms of heterodyne detection, in the middle of the test frequency shift skills though as soon as you start now, but because of the power equipment is not high and increased the complexity of the optical system, it is difficult to get.Most of the early signal processor chooses the existent spectrum analyzer, use it to process the data, accuracy is poor, mostly is unable to get the instantaneous pulse rate.Home also have a beginning, under the guidance of Wang Dayan, in April 1966, the Chinese academy of sciences (changchun) optical precision instruments machinery research developed by remote control pulse laser doppler velocimeter.When have someone start r&d frequency tracker and counter type processor, but also as a prototype just to stay in the laboratory.Therefore, in this period, the activity measurement, are mostly under the condition of low turbulence, test results is given priority to with even distribution. |
