Antenna Performance Measurements at L, S, C, and X Bands for the TM65m Radio Telescope☆☆☆

Abstract In this paper, we reported the measured results of the antenna efficiency, sensitivity, and system noise temperature of the TM65m radio telescope. The key parameters describing a radio astronomy receiving system were introduced at first. Then, we discussed the measurement methods and the measuring errors. Finally, the measured results of the antenna efficiency, sensitivity, and system noise temperature performances at the L, S, C, and X bands were given. The results show that the efficiency and SEFD (System Equivalent Flux Density) decrease dramatically at both low and high elevations when the position of the subreflector is fixed. The antenna efficiencies at the C and X bands can be raised to 60% and more in the whole elevation range when the subreflector (servo) model is activated. The system noise temperature is independent to the subreflector model. Among the four wavebands, the C-band sensitivity and system noise temperature are optimal.