A pointing error analysis model for large reflector antennas under wind disturbance

摘要

Large reflector antennas have been widely used in extensive researches, including satellite communications, detection of gravitational waves, origin of galaxies, and so on. With increasing in the diameter and the working frequency of these antennas, the requirement for pointing accuracy becomes more demanding simultaneously. However, wind disturbance has serious impacts on the pointing accuracy of antennas, which makes it be a severe challenge to the development of large antennas. To reduce the influence of wind disturbances on pointing accuracy, it is important to construct an accurate model for estimating the pointing error caused by wind. The traditional modeling method focuses on treating the wind disturbance as a torque on the motor output, whilst ignoring the oscillations of flexible structures caused by the wind pressure, so the pointing error caused by structural deformation cannot be estimated which lead to a limitation of compensation effect. In this article, based on an entire working condition dynamic model (EWCDM), a pointing error analytical model is proposed to estimate the pointing error caused by deformation of the antenna structure. A series of simulations and tests are carried out on an antenna with a diameter of 7.3?m. The results prove the feasibility of the proposed model.