Development and Realization of a Q-band Receiver

The Xinjiang Key Laboratory of Microwave Technology for Xinjiang Astronomical Observatory has designed a Q-band receiver at room temperature. The Radio Frequency of the receiver is 30-32 GHz, after mixing and filtering, the Intermediate Frequency of signal is down to 1.985-2.015 GHz and finally to output. This receiver is mainly used to build an independent Q-band atmospheric opacity measurement system, so as to carry out accurate amplitude calibration in the Q-band scientific observation of Nanshan 25 meter telescope. The receiver is mainly composed of Q-band ultra wideband corrugated horn with small opening angles, ortho-mode transducer with cross knuckle type and back stage microwave link. After the development, the dynamic range of IF output spectrum of the receiver is about 37 dB (-48.3 ~ -85.4 dBm), and the total power output is about -29.86 dbm. Subsequently, the real-time atmospheric opacity value can be obtained by combining the atmospheric radiation transfer equation and elevation scanning nonlinear fitting method.