| Doppler navigation radar is a very important kind of airborne navigation aid. In the past, as a result of technical and the condition limit, many portions of signal process in radar are designed with analogue electronic technique. At present, with the high speed development of digital signal process, it is necessary to realize signal process radar to enhance its performance, reduce its volume and weight. Then the increasing demand of plane to Doppler navigation radar will be satisfied.In the paper first introduced the basic concept and the principle of navigation and Doppler radar. The spectrum characteristic of echo signal and its influence to the frequency measurement precision is analyzed emphatically. Then the paper makes theoretical analysis and the simulation to each part of Doppler radar signal process, mainly including the digital orthogonal demodulation, the modulation and the zero frequency suppression, the noise abatement, the Doppler frequency estimation, velocity tracking and so on. Doppler frequency estimated uses the partial Zoom FFT method, that increases the precision of frequency measurement greatly. Finally the paper introduces the whole realization plan of a kind of airborne Doppler radar as well as the realization method, including the composition of Doppler navigation radar signal receiver, the working mode and the cycle, the algorithm and the realization of all function modules, the hardware and the software flow designing of multi-pieces DSP that working jointly to carry on signal process, etc. The test result is offered in the end. |
PDF Full Text Request