Application Of Digital Receiver In Weather Radar

Traditional weather radar' s receiver mainly uses instantaneous automatic gains control to expand dynamic range. It demodulates the signals by using I/Q simulate demodulator, which strongly depends on the receiver' s hardware as it has weak capabilities to adapt. The software radio technology' s appearance brings the renovation of wireless receiver. With the fast developing of components level, digital receiver also matured gradually and widely used in radar, electric war and communication receivers.This paper discusses the applications of digital receiver for weather radars. In the first part, the band-pass sampling is introduced before everything, which is the theory foundation of intermediate frequency sampling. After that, the realization of digital frequency down conversion and main components used are discussed. In the second part, from the point of view of receiver system, main components, which may affect the target, and the key points in using digital intermediate frequency, is analyzed in very particular by deducing of formula and simulating in MATLAB. At the same time, digital intermediate frequency' s dynamic expanding is analyzed and explained according to the characteristics of weather radar. It mainly includes ADC noise analysis, ADC false response, affection of aperture jitter to the system and so on. In the last part, it is discussed the designing and calculating of digital receiver in weather radar, and the results of real system' s test are also given.