This article aimed at the high antenna gain and the narrow beam of ship-borne large-scale monitoring and control system, the low bootstrap antenna gain, wide beam, analysing the differences of the antenna error voltage and signal level intensity received in the main antenna system,combining the nonparallelism of the antenna power - electricity, formed a comprehensive criterion, the ACU engineering application software to achieve the main switch automatically, the sidelobe track recognition, and ways of working to achieve their own self-tracking and other functions.