The Research And Realization Of Large Radio Astronomy Anti-jamming Based On LMS

Radio astronomy observes the electromagnetic spectrum usually from 10MHz to approximately 300GHz. Radio astronomy observing Passively receives extremely weak radio signals from the universe, which is vulnerable to active business activities. Located a better site the Radio Astronomy Observatory Five-hundred-meter Aperture Spherical Telescope (FAST) is more difficult to be effected ground electromagnetic interference, but interference from the satellite navigation signal is inevitable.For radio astronomy Interference antenna research, many foreign experts and workers have many fruits. Through researching and comparing, this paper made the evaluation criteria on radio astronomy: improving of Signal-to-Noise, stability of weight gain, the residual interference, the performance of real-time and computation.In order to suppress and eliminate the navigation satellite signal interference during observing using FAST radio telescope, finally integrate the published program, compare and design a solution. Use the adaptive filter algorithm and fit two auxiliary antennas, to eliminate the navigation satellite signal interference.For carry out the adaptive filter algorithm, as a result of the incorporative LMS (least mean square)algorithm has high residual interference and improvement of degree of signal to noise ratio, improve and put forward the separability LMS algorithm. Simulate the separability LMS algorithm, incorporative LMS algorithm, compared to the their performance of signal in the mean square error, weight gain, the residual interference, improvement of degree of signal to noise ratio, real-time and computational, make conclusion that the separability LMS algorithm is well to incorporative LMS algorithms in the residual interference and improvement of degree of signal to noise ratio. The separability LMS algorithm is feasible.For validating the feasibility of the separability LMS algorithm, this paper design the test system which use the FPGA of Altera Corporation realize the separability LMS algorithm.For radio astronomy anti-jamming system subsequent use of the processing required, prepare a software that can use high-speed data acquisition 7300 card to display parameters in real time processing the hardware platform interference, and can quickly save the parameters. Also achieved a serial transmission capability can use RS232 testing outdoor.Finally make elementary test for the test system, validate the impression of separability LMS algorithm.