High-speed Data Acquisition System Is Developed

In radar signal and information processing system, data acquisition system is indispensable as a very important unit. In modem radar system, wide or ultra wide band radar signal is used more widely. Accordingly, by using digital signal processing, we need high-speed data acquisition system to get information. In traditional radar receiver, the consistency of phase-and-amplitude is imperfect, which limit the performance achievable from signal processors. To overcome this problem, we think to digitized the signal at medium frequency, even RF, and then demodulate it in digital domain. In the same, only the high-speed data acquisition system can satisfy the requirement. Based on the high-speed data acquisition system, this dissertation compares the digital receiver with traditional receiver. And we consider that it is feasible and necessary to get information on high-speed data acquisition in RF. About the data acquisition system抯 performance, we get the method of evaluating the system by theory of quantification. Combining with theoretical analysis, design and develop a suit of high-speed data acquisition system with up to 600MHz sampling frequency. The test indicates that it can satisfy the project and the effective bits is 7.45. At present, the data acquisition system with up to 600MHz sampling frequency is rarely reported in our country. So it has good application foreground. The major contents of this dissertation as below: (1) Analyze the consistency between the traditional receiver and digital receiver in detail. The theory and the excellence of the digital down converter are also analyzed. And introduce the DPD technology based on orthogonal sampling. (2) Discuss the theory of quantification, analyze the method that how to get the effective bits. (3) Introduce the design of the high-speed data acquisition system. (4) The performance of the high-speed data acquisition system is tested. The acquisitive data is analyzed and processed.