For traditional calibrating method of the antenna angular reference of landing guidance radar, a large amount of electromagnetic radiations is unavoidable, the capacity of resisting disturbance is lower and the work is inefficient. An improved method is proposed. The measured antenna received small signal instead of transmitting large signal during the testing procedure. Three axis programmable turntable and servo controller were adopted at far field testing to control the horn antenna move precisely, and working with the near-end operational software. The horn antenna can be remotely controlled between the distance of the 150 to 250 meters. Peak-seeking automatically and data logging and storage were realized as well. Compared with the traditional calibrating method, the electrical radiation reduced to 1 ∶ 850 000,the testing stuff reduced from 4 to 2 and the testing time reduced from 5 hours to 0. 5 hour. The improved calibrator which is proved by the experiments can replace the old one completely.