The accurate measurement and compensation of the antenna structure deformation are helpful to improve the pointing accuracy of the radio telescope and improve the observation performance.

The deformation of alidade is one of the main reasons that affect the pointing accuracy of the antenna. However, it is difficult to measure the pointing errors caused by structural deformation in real time.

Researchers from the Xinjiang Astronomical Observatory (XAO) of the Chinese Academy of Sciences designed a high-precision measurement method for the deviation caused by the deformation of the antenna alidade and measured the Nanshan 26-meter radio telescope.

They obtained the deviation data related to the deformation and tilt of the antenna alidade caused by the uneven antenna track and the solar irradiation respectively. The pointing errors of the antenna azimuth and elevation direction are obtained by space conversion, and compared the pointing errors obtained by this method with astronomical pointing observation.

The study was published in Micromachines on June 22, 2023.

They found that this method can be used to accurately measure and compensate for the tracking error of the antenna, and accurately obtain the pointing error caused by the deformation and tilt of the antenna alidade, so it is expected to realize the accurate real-time compensation of the pointing errors.

Moreover, the results also showed that the antenna alidade has an obvious tilt trend in azimuth and elevation direction, which is related to the deformation caused by the uneven irradiation of the sun.

comparison of thermally induced pointing errors measured by astronomical observation and by the measurement system 

Contact: XU Qian

Xinjiang Astronomical Observatory, Chinese Academy of Sciences

Email:xuqian@xao.ac.cn

Article link:  https://doi.org/10.3390/mi14071283