Antenna beam angle calibration method via solar electromagnetic radiation scan

Abstract

Regular calibration is essential to antenna beam-pointing angle of mobile radar considering system errors caused by the transition to a new site or deformation of the radar antenna structure. Traditional antenna beam-pointing calibration methods based on calibration towers, aircraft etc. are more widely used. However, these calibration methods are either too complex or too expensive for mobile radar. Since solar has relatively stable radio intensity and its angle of view can be accurately calculated, this study proposed a fast antenna beam pointing calibration method by using solar electromagnetic radiation as a calibration reference. In this method, radar controls its antenna beam pointing to the predicted observing angle of solar and tuning the antenna beam to scan the sun on azimuth and elevation until the amplitude of received radio signal achieved its maximum, then the azimuth and elevation of antenna beam is the value for antenna beam-pointing calibration. Finally, this study verified the validity of the calibration method by the real calibration data of radar. This method has been applied to a mobile radar with a 0.5° beam width. The results show that the integrated error of the calibration can be <0.01°.