General Wide-Band Signal Generator Module Design And Realization

Wide-band signal plays impotant part in improving the resolution in range domain, so the design of wide-band signal becomes an impotant technique during the modern radar development. In this paper, a new advanced general wide-band signal generator module is developed, which uses high speed FPGA as its control-unit.The module can work in any system with different bandwidth and can generate any kind of LFM signal, whose bandwidth is less than 200MHz, and time-width is less than 870us. With the design and realization of the module as the background, the elementary theory of LFM signal,the detailed structure of the module,the systemic performance analysis,evaluation and optimization are discussed in this article. The paper is composed of four parts:First, the elementary theory of LFM (Linear Frequency Modulated) signal is studied. Based on the theory of pulse compression, the essentiality of LFM signal is discussed. Meanwhile some methods that generate LFM signal in digital or analog are provided in this part.Second, the design and realization of general wide-band signal generator module are studied. The conformation and the key unit of the system are discussed. Meanwhile the generalization of the module is realized base on using FPGA as the control-unit.Third, this dissertation focuses on the error analysis of digital method of the pulse compression signal generation based on LFM signals. Except, the error model is established here.Fourth, pre-distortion calibration technique is studied and applied to improve signal quality, meanwhile the software is developed. Finally the generator module is tested and evaluated. The author provides the testing measure and result.The production of this dissertation has been successfully applied to many radar system, and proved to be feasible and efficient.