Research On Two Dimensions DOA Estimation Method Of Shortwave Signals

With the development of the electronic technology and communication technology, Direction Of Arrival (DOA) estimation method has extensive applications in civilian and military fields.DOA estimation method is approaching maturity in theory. However, there are still many problems to need to be further investigated in engineering applications. Based on the practical application requirements, this thesis focus on the two-dimensional DOA estimation method for shortwave signals. First of all, some problems in practical applications are thoroughly analyzed, and then some solutions are presented. The main work of this thesis includes:1. Systematically analyze and summarize the DOA estimation algorithms for narrowband signals. Compare and summarize some classical algorithms in performance and array configuration restrictions, including conventional DOA estimation method and cyclostationarity-based DOA estimation method.2. An optimal design of array configuration is proposed. The proposed array configuration can achieve stable performance within the whole shortwave band, and can apply ESPRIT algorithm and spatial smoothing algorithm. The proposed array configuration can solve the problem in uniform array that satisfactory performance is difficult to achieve under a large range of the signal wavelength.3. A new robust DOA recursive estimation algorithm based on cycle adaptive beamforming is proposed. The proposed algorithm can achieve robust DOA estimation performance in complicated scences such as in the presence of cycle frequency error, time varying cycle frequency, moving radiation source and time varying array position error.