| The HF Surface Wave Radar (HFSWR), which has been dramatically developed in recent40years, is a ocean remote sensing equipment that can monitor a large zone continuously. Based on the scattering theory of the interaction between HF radio wave and the sea surface, the HFSWR extracts ocean dynamics parameters such as wind, wave and current by observing and analyzing the sea echo signal. The HFSWR has a wide coverage area, high accuracy of detection, good real-time performance and good all-weather adaptability comparing to other ocean remote sensing equipment. Hence, the HFSWR is the necessary supplement of ocean remote sensing equipment and remote sensing method and it's considered to be one of the best methods to monitor ocean environment.Spatial spectrum estimation algorithms have been introduced to extract the sea surface current information from the sea echo received by the HFSWR. Though the super-resolution detection finding technology based on subspace decomposition has many potential advantages such as high accuracy of resolution and detection of multiple DOA values at the same time in theory, all these merits based on the assumption that the array manifold is certainly known. Since all sorts of errors (include the array position disturbance, mutual coupling, array gain-phase errors, etc.) can't be neglected in practical engineering application, certain deviation and disturbance will occur in the actual array manifold. According to the theoretical analysis and experiment results from many journals, the detection finding performance of the super-resolution detection finding algorithm degrades dramatically when there exists array errors. Hence the relevant offset and calibration measures should be taken.It's difficult to use several stable calibration sources with high SNR of which number is more than the number of array element to process the active calibration or self calibration because of the restrictions of environment around the HFSWR. Thus, the main research of HFSWR array errors calibration aims at the relatively stable single DOA sea echo or hard target echo to process the array gain-phase errors calibration. Supported by distributed HF over the horizon radar detection and networking technology study of national863Program, I focus on the active calibration of array errors of distributed HFSWR in this thesis, take the orthogonality of orthogonal projection matrix as the theoretical foundation, use the Gauss-Newton gradient algorithm and genetic algorithm as the main method and finely discuss the active calibration of array errors algorithm in accordance with the features of mutual coupling by principle introduction, simulation analysis and processing of experimental data.The whole sketch of this thesis:1^The array signal model is built. According to this model and the coupling features, the active calibration of array errors algorithms of distributed HFSWR can be divided into two types. One active calibration of array errors algorithm can neglect the mutual coupling between different channels. Under this assumption, the coupling parameter value is relevant to the array element distance so that the mutual coupling matrix can be set by the array element distance. The other active calibration of array errors algorithm can consider the mutual coupling between different channels In this condition, coupling coefficient is irrelevant with the array element distance. Since the number of coupling parameters is large while the number of direct wave calibration source is limited, it is necessary to combine the high SNR sea echo and the hard object echo to do the joint estimation.2,The basic principle of the selection of the single DOA sea echo is introduced. Array calibration method for the consistency of gain-phase based on the single DOA echo is proposed and the comparative analysis of experimental results is shown. By analyzing the FMICW, I propose an array calibration method for gain-phase errors by using asynchronous interstaion direct wave interference (IDWI) and show conditions and probability of the generation of IDWI and the characteristics of asynchronous IDWI. This method can implement calibration of direct wave without keeping radar stations in synchronous condition. The comparative analysis of experimental data demonstrate that using array calibration for gain-phase errors based on asynchronous IDWI can get accurate and stable calibration values of gain-phase errors.3,I provide two methods to acquire the initial value of array errors:pseudo-inverse algorithm and genetic algorithm. The simulation results show that the estimation performance of the two methods is very close. Then, three specific algorithms have been put forward according to the number of calibration source of direct wave and different coupling conditions. Without the mutual coupling between different channels, the algorithm of active calibration of array errors based on direct wave is used for the multiple calibration sources of direct wave, or based on the direct wave and RF disturbance array is used for the single calibration source of direct wave. When the mutual coupling between different channels is considered, the algorithm of active calibration of array errors based on direct wave and sea echo is provided. These algorithms have been proved valid with the simulation and experiment data.4,By introducing the HFSWR based on buoy, the buoy motion signal model is provided for the buoy movement on the sea surface. Then the basic principle and algorithm for the motion state estimation of buoy are provided and also proved valid through the simulation. According to the specific conditions of the HFSWR based on buoy, the algorithm of active calibration of array errors based on direct wave has been improved, and I propose an algorithm of array errors active calibration for HFSWR based on buoy. The simulation results demonstrate the effectiveness of the algorithm.
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