Realization of an Azimuth and Elevation Adjustable Control Platform

Microwave receiver is special equipment for receiving radio signal in radio telescope and the purpose of amplitude calibration is to equivalently convert the response of the received radio signal to astronomical flow density. Since millimeter wave calibration is also susceptible to atmospheric absorption, the measurement of atmospheric opacity is particularly important. In this paper, by building the mechanical rotation platform and its control system, the 7 mm band normal temperature receiver can accurately realize the 0° ~ 90° pitch scanning observation at the target azimuth. The output power of the receiver in different elevation angles can be recorded in parallel by the control software. Combined with the atmospheric radiation transfer equation, the nonlinear least square fitting method is adopted to finally obtain the current azimuth 7 mm band real-time atmospheric opacity value. The precise control and the automatic test function are well realized.