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Given the rise of satellite television, radio telescopes in the Ku‐band (12–18 GHz) constitute a potential alternative to introduce low‐scale astronomical observatories and amateur astronomers to radio astronomy. In this paper, we show a methodology for the calibration of Ku‐band radio telescopes and the evaluation of the techniques used for the observation of celestial bodies in this frequency range. To reduce the pointing error, we present a method of observation through matrix windows around the Sun. By observing the solar transits, our methodology allows to determine the system temperature, the beamwidth, the gain, the effective area, and the efficiency of the radio telescope. In addition, we developed the Compact Radio Telescope (CRT) software, designed to perform the calibration, and carry out observations. We tested our methodology with the Ku‐band radio telescope of the Observatorio Astronómico of the Universidad Tecnológica de Pereira (OAUTP), Colombia. After observing the Sun and the Moon, we obtained a brightness temperature of 8,600 ± 800 K and 240 ± 50 K, and radiation fluxes of 2,970,000 ± 690,000 Jy and 55,000 ± 10,000 Jy, respectively. These observations demonstrated the usefulness of our methodology and CRT software in the calibration of compact Ku‐band radio telescopes for the observation of celestial bodies in radio waves. [ABSTRACT FROM AUTHOR]

An almost all‐metal L band multi‐frequency high‐gain GNSS array antenna for an asteroid sampling return mission has been developed for orbit determination. The proposed antenna is designed for reception and is compatible with Beidou and GPS at L‐band (i.e. GPS‐L1: 1575.42 MHz; BDS‐B1I: 1561.098 MHz; BDS‐B2a: 1176.45 MHz). The radiation element is an almost all‐metal dipole with structure improvement, and thereby strong enough to handle vibrations and loads. The array antenna is composed of the 7‐radiation element and a low loss air suspended stripline beam‐forming network. The six elements around the center element have uniform distribution, while the center one is excited twice amplitude than outer ones for appropriate gain and beamwidth. A prototype of the proposed GNSS array antenna is designed in a simulation and measured in an experiment. The simulated and measured results agree very well, showing that the reflection coefficient <−17.5 dB over 32.8% bandwidth from 1.1 to 1.7 GHz is achieved with rotationally symmetric radiation patterns and gains >13.4 dBic, 15.2 dBic, 15.2 dBic at BDS‐B2a, GPS‐L1, BDS‐B1I, respectively. [ABSTRACT FROM AUTHOR]