Short-wave Frequency Wideband Direction Finding Key Algorithms Of Test System

It becomes increasingly important to measure and trace the position of incomingsignals, due to the complexity of signal forms and the diversity of signal in modernelectronic warfare environments. The correlative interferometer direction findingsystem has become the core technology of broadband direction finding because of itssimple algorithm、high speed of direction finding and accurate precision.The dissertation takes the broadband interferometer direction finding system asbackground and studies the key algorithms in the broadband interferometer directionfinding system. It organizes as follows:1.Aiming at the problem that the phase may hop in the main interval during theprocess of broadband interferometer direction finding, the cosine function is applied tothe correlative interferometer direction finding system and the problem is solve to acertain extent.2. Aiming at computing intensive problem of the correlative interferometerdirection finding algorithm, the concept of the space angle is applied to the correlativeinterferometer direction finding system. The introduction of the space angle, whichturns azimuth、pitch angle two-dimensional information into one dimension andtherefore reduces the computation of the related operations.3. A new algorithm, which is based on parallel baseline in uniformly circular arrayinterferometer, is proposed which make use of the feature that the parallel baselinefuzzy numbers bear a linear relationship. With this new algorithm direction cosineestimation can approach to the lower limit of the Cramer Lauro and the computation ofthis algorithm is relatively small under certain signal to noise ratio circumstances.4. In order to improve the real time performance of direction finding system, thepart of the correlative interferometer direction finding algorithm based on space angle istransplanted to GPU, which greatly reduce the execution time of the algorithm.The work mentioned above has been verified through simulation. Simulationresults verify the correctness and effectiveness of the application of cosine function andspace angle to correlative interferometer direction finding system. Simulation results also proved that the algorithm of uniformly circular array phase interferometer based onparallel baseline not only guarantees direction finding accuracy but also reduces thecomputation. Finally, the simulation results show that the GPU processing performanceis preferable to that of CPU.