High Performance Pulse Linear FM Signal Generation Research

With modern technology and digital VLSI technology, the radar signals using digitalmethods have been universalized. But even more distant future, pure digital microwavesystem will not satisfy the requirements wideband radar signal. This requires signalgenerator is the technology should be a hybrid of digital technology and analogtechnology. Theory shows that the decision to radar detection systems'detection andparameter estimation accuracy, and resolution is the transmitted waveform. Consideringtransmitted waveform, the wider of the signal bandwidth, the more favorable resolutionthe system would come to. LFM which is the first practical application has long plusand wider bandwidth, but also easy to implement. Moreover, it is not sensitive target toDoppler frequency shift. At the receiver, pulse compression technology can solve thecontradiction between the resolution of detection range and distance. LFM signalbandwidth is generally from several decades to several hundreds MHz. The bandwidthof the transmitted signal of precision tracking radar and synthetic aperture radar isseveral hundreds MHz. In recent years, the technology of using digital signaltechnology in LFM signal generating become the hotspot in domestic universities andresearch institutes. However, the general pulse frequency signal source product has notyet been reported.This paper studies around the LFM signal technology to do some work on the theoryand practice. The purpose of this project is to develop a common pulse frequencymodulation signal generator. Its parameters can be set by the user. It achieves the radarsignal simulation. More detailed on two digital technologies, as waveform storagemode(DDWS) and the accumulator means (DDFS), generating a base band signal and therealization of the principles of the program is discussed on the paper. And on the basisof this analysis of a variety of signal bandwidth expansion technology, the paper bringsforward the realization of universal linear FM signal source programs. AD9852ASQDDS chip which is the product of AD corporation is used to achieve the basebandsignals. And a lot of analysis is done to the baseband. The works of the paper provide the theoretical and experimental data needs to the eventual realization of the program.