Design And Implementation Of Satellite-Based IF Transmiting System

With the development of aerospace technique' progress and military aerospace' s demands, every country pays more attention to the satellite' s observe and control techniques. In the observe and control system, Satellite-based IF receivce and transmit system, which is acts as a link between base-band signal and transmitting antenna, has very significant meaning to the system' performance. For a long time, our country till using the analog IF receive and transmit module, digital module is just makes the first step. With great improvement of software radio techniques, digital signal process techniques and micro-electronic techniques, digitalize technique grows to be perfect, to digitalize IF transmit system is becoming a serious task.The software radio is a great innovation in the wireless communication field. Which presents theory foundation for the wireless communication system to be miniaturization and intelligence. Software radio system is a complex digital dignal process system, which greatly expands the investigating field of the digital signal process. Using software radio, this paper set up a model of the system, and demonstrates the realization of the model.By Studying the relevant materials and nowdays techniques, the paper talks about the consists, structure and function theory of the IF transmit system, establishes a universal flatform, programming a main processing model for the hardawre exploiting program with the Verilog HDL programm language, explains the function theory and apply method of the direct digital synthesis(DDS), presents a scheme for the phase modulation system' s key technique. The main content of the thesis includes: the digitization of the base-band, the orthogonal of the digital base-band signal, design of the DDS phase modulation and digitization attendant of the output singal.