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Space-based optical images are mainly affected by space radiation, sky glow background and CCD noise interference, in which space radiation noise can seriously interfere with the subsequent target detection. In this paper, we propose a space radiation interference suppression algorithm based on multi-feature, and compare with three algorithms which are commonly used to eliminate radiation noise: a Laplacian edge detection algorithm, a fast algorithm based on histogram and a rank-ordered absolute difference (ROAD) algorithm. The experimental results show that the proposed algorithm can quickly and effectively eliminate space radiation noise.

This paper presents the concept of a passive bistatic radar (PBR) system using existing phased array radar (PAR) as the source of illumination. Different from PBR based on common civil illuminators of opportunity, we develop an experimental PBR system using an high-power air surveillance PAR with abundant signal modulation forms as the transmitter. After the introduction of the PBR system and PAR signals, it can be concluded that the agility of the waveform parameters of PAR signal brings two problems to the signal processing of the PBR systems, which are not discussed in conventional PBR systems. The first problem is the time and frequency synchronization of the system, so we propose a direct wave parameter estimation method based on template matching to estimate the parameters of the transmitted signal in real time to achieve time and frequency synchronization of the system. The second problem is the coherent integration for moving target detection and weak target detection, so we propose a coherent integration method based on Radon&ndash, Nonuniform Fast Fourier Transform (Radon-NUFFT) to deal with the problems introduced by the agile waveform parameters. Preliminary results from the field experiment demonstrate the feasibility of the PBR system based on PAR signals, and the effectiveness of the proposed methods is verified.

With regard to target detection in high resolution panorama images attained by circumferential scan Infrared Search and Tracking system, a rough-to-meticulous real-time target detection algorithm is proposed based on analysis of characteristics of targets and background. In the rough detection phase, it attains initial high rate target detection by quick real-time algorithm, based on the gray high frequency and movement characteristics of the target in the whole panorama image. In the meticulous detection phase, focusing on the detected suspected target sliced images, it has further delicate detection and recognition on the basis of targets’ characteristics to exclude those false jamming. The detection result of the test images shows, the algorithm enables stable detection with low-rate false alarm for distant dim small targets, and has been applied to the development of engineering sample of the Panorama Infrared Search and Tracking system.

A Gas chromatography-mass spectrometry (GC-MS) data analysis algorithm is proposed. The mass spectrum at the top of the chromatographic peak is the spectrum to be solved. A certain amount of related reference spectra is retrieved from the spectral library, then, the equation of the chromatographic response value of each pure component is solved. A step by step strategy is used for the mass spectra retrieval. Firstly, an efficient indexing technology is used for rough selection, then, the "strong peak out with high probability" and the "extrusion" rules are used to exclude more unrelated mass spectra. A regression algorithm based on a sparse model is proposed to solve the equation of the chromatographic response value. Compared with the traditional algorithm, this algorithm can extract the main structure of the spectrum to be solved, and avoid over-fitting. The experimental results show that the proposed algorithm has a higher accuracy and smaller residual reference spectrum set, and the sparse model achieves satisfactory experimental results in the analysis of severely overlapped peaks. The proposed method provides an effective solution for resolving overlapped peaks, especially severely overlapped peaks, in GC-MS data.