Yang Wan-lin

Joint DOA and time delay estimation method for space-time coherent distributed signals based on search

Abstract Under dense urban fading environment, performance of joint multi-path parameter estimation method based on traditional point signal model degrades seriously. In this paper, a new space and time signal model based on multipath distribution function is given after new space and time manifold is reconstructed. Then joint spacetime signal subspace is obtained by converting acquired channel from time domain to frequency domain. Then space and time spectrum is formulated by the space sub-matrix and time sub-matrix taken out of joint space-time signal subspace, and parameters are estimated by searching the minimum eigenvalues of the space matrix and the time matrix. Lastly, A space and time parameters matching process is performed by using the orthogonal property between joint noise subspace and the space-time manifold. In contrast with tradition MUSIC, the algorithm we present here only need two 1-dimension searching and was not sensitive to difierent distribution function.

A refuse-recognition method for radar HRRP target recognition based on mahalanobis distance

In the radar automatic target recognition (RATR) system using high resolution range profile (HRRP), if a test sample has not been trained in training phase, it would lead to a full miss classification in test phase. In this paper, we design a classifier based on generalized confidence, which can efficiently refuse-recognize a new target. Firstly, principal component analysis (PCA) method is used to extract feature vector from every sample. Secondly, the classifier calculates each feature vectors generalized confidence on mahalanobis distance. Consequently, the distribution of confidence is used to define a refuse-recognition threshold for each training target. In test phase, for each trained-target in the database, we suppose that the test sample belongs to current target, calculate the generalized confidence, judge whether the test sample really belongs to the target or not via comparing the confidence with the targets refuse-recognition threshold. The final class is determined by vote. The experimental results demonstrate the effectiveness of the proposed algorithms.

Direction of arrival estimation and identification of mixed circular and non-circularity sources

Most of existing array signals processing methods are based on the homogeneous circular or non-circular sources. However, mixed circular and non-circular sources are frequently encountered in increasingly complex situations. Since the useful properties of the mixed source model are not utilized efficiently, there is significant performance space between the methods based on homogeneous source model and the theoretical bound. In this paper, an enhanced direction-of-arrival(DOA) estimation and identification method for mixed circular and non-circular sources is proposed. Simulation results show that it can improve the resolution capability and the number of mixed sources can be larger than the number of array elements.

A novel GPS antijamming receiver based on noncircularity

We present a novel antijamming global position system (GPS) receiver that relies on the unique noncircularity of the GPS signal. Since the GPS signal is BPSK modulated, it is a noncircular signal while most interferers are circular signals. The proposed receiver utilizes this circular difference property to excise interferences while preserve the GPS signals. It is shown that the proposed receiver is a blind receiver that does not require any angular information of the satellites.

Bistatic SAR Imaging Based on Range-Doppler Algorithm Without Interpolation

Imaging approach based on range-Doppler algorithm for monostatic SAR is extended to bistatic case. Because of that the transmitter and receiver are located separately, the range cell migration phenomena of bistatic SAR is more complicated than that of monostatic case. In this paper, a simple method of range cell migration correction is used instead of interpolation operation in traditional range-Doppler algorithm for monostatic SAR. Point scatter response, range and azimuth resolutions are also discussed. The simulation results are presented.