Design Of Radio Astronomy Receiver Based On Software Radio

Radio astronomy is an important research field of astronomy.Radio astronomy uses radio reception technology as an observation method,and the observation objects cover all celestial bodies.Observation of various celestial bodies in the universe is one of the main contents of radio astronomy.Observation of celestial bodies can provide important scientific experimental data for celestial dynamics,gravitational physics,dense astronomy,and exoplanet research.At present,in many scenarios,digital receivers are required to observe signals in different wave bands,but are limited by the RF front-end.Many digital receivers themselves can only receive fixed-band signals for analysis and processing.In the field of radio astronomy scientific observation activities,It is often necessary to lay out observation equipment in large quantities,and the portability and cost factors of the equipment become a problem.There is a growing demand for wideband,multi-channel,and smarter radio receivers.This paper designs a smart radio astronomy receiver system that can support multi-band observations,including a radio frequency front-end,and six-channel input in response to the various requirements of radio astronomy receivers in existing scenarios.First,the main research work on radio astronomy receivers at home and abroad was investigated,and it was decided to use the software radio architecture to design this radio astronomy receiver system.Then completed the design of the receiver system hardware platform SDR core board and digital main control board.The SDR core board is responsible for the reception,amplification,filtering,down-conversion of the six-channel RF signal to baseband and analog-to-digital conversion to digital signals.The digital main control board is responsible for receiving data from the SDR core board and performing subsequent signal analysis processing.The core board and the main control board interface use the same high-speed interface as other largescale signal processing FPGA and other modules used in the laboratory-designed ARM-RSR and other designs,so that they can form a larger scale with those modules in future applications.'S radio signal processing system to cope with more complex and demanding application scenarios.Then completed the internal digital signal processing logic design of FPGA,and realized the functions of decoding,synchronizing,packaging and transmitting the sixchannel data to the host computer.Then the software system was designed,including the main control module based on the PS terminal and the host computer software.The main control module realizes the control of the underlying hardware and the LWIP communication module through C language.The upper computer software part uses Matlab to realize the GUI design and integrates a variety of instruction sets.Users can realize data interaction by sending instructions and the main control module,so as to directly read and write parameters of various hardware registers,so as to configure different working modes of the system.Finally,the entire system was tested carefully and comprehensively,including host computer software test,external local oscillator test,and system receiving channel test.The experimental results showed that the designed radio astronomy receiver system met the requirements of the index.