A Research Of Modulating Pulse Intellective Synthesizing On Modern Phase-Array Radar Transmitter

Along with the development of military innovation as well as the appearance of new material and technique, improved performing radar is imminently required. Phased-Array radar is one of the mainstream branches of modern radar. The high performing Phased-Array radar is worth researching in the long term.A new research on the modulating pulse's generation of transmitter used in modern Phased-Array radar has been introduced in this paper. Firstly, the principle of the Phased-Array radar and its transmitter are briefly presented. Traditional methods can't meet the needs of Phased-Array radar's demands for higher power and multi-function use, for some flaws, especially the waveform distortion serious problem raised by the serious top descending of waveform. Therefore, a new scheme of generating radar's modulation pulse is discussed.At the beginning of this paper, two or more intellective sub-pulses will be generated and adjusted based on a FPGA (Field Programmable Gate Array) system, which is controlled by the synchronization pulse provided by radar. These sub-pulses have the same frequency and amplitude. However, they have different duty cycle and orthotropic phase, which could be controlled totally.Firstly the basic parameters and design principle of pulse transformer and the parameter calculation of waveform are discussed. In order to control the DC supply to yield pulse with high voltage, then each power MOSFET, locating in the high voltage transformer circuit, is driven by an isolated and amplified sub-pulse. After increasing voltage in transformer these high voltage pulses will be composed to a new modulation pulse. Then the realization of distributed research method is discussed. At the same time, the important block diagrams, schematic diagrams and PCB diagrams are presented in this paper as well. the waveforms in output port of synchronizer and system modulating pulses are sampled from oscillograph, then presented, compared and discussed. The final data suggest that the original assumption has come true, and modulating pulses with new method have better performing. The design with new method could decrease the design cost largely, and improve the integration rate and the anti-interference character. Finally, the author optimized the code, and the paper also put forward some problemsneed to be deeply investigated in the future.