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The wireless channel model, which was suitable with the complex environment of battlefield, was built by analyzing the digital image of wireless transmission channel, the transmission characteristics and the fading type. The error correction of coding for the compressed code stream of image was carried out specifically with Turbo code, and the Simulink simulation model was designed. The system simulation analysis was carried out for the performance parameters that affect the Turbo code and the BER performance of as-built wireless channel model. The results showed that the Turbo code is a kind of error correction one, which is anti-fading and strong interference among codes. It can not only reach higher peak signal to noise ratio, but also transmit more steadily and more reliably in the changeable channel environment under noise interference. Furthermore, the turbo can be applied for code correction and controlling.

In order to improve the degree and real-time of the vehicle image detection, a background extraction method based on the probability mean value method and the background update based on the weighted coefficient method through divided area are proposed through the acquisition of real-time traffic information and processing of video images for intelligent transportation systems. Finally a prototype of background extraction and background update is got, and it achieves the detection of moving vehicles. The experimental results show that this method is simple, small amount of calculation and it has a good robustness; it can extract a good background image quickly and detect a complete shadow of vehicles. So this method can meet the requirements of real-time detection of multiple moving targets.

Ballistic missile defense system (BMDS) is a weapon system for intercepting enemy ballistic missiles. It includes ballistic-missile warning system, target discrimination system, anti-ballistic-missile guidance systems, and command-control communication system. Infrared imaging detection and laser imaging detection are widely used in BMDS for surveillance, target detection, target tracking, and target discrimination. Based on a comprehensive review of the application of target-detection techniques in the missile defense system, including infrared focal plane arrays (IRFPA), ground-based radar detection technology, 3-dimensional imaging laser radar with a photon counting avalanche photodiode (APD) arrays and microchip laser, this paper focuses on the infrared and laser imaging detection techniques in missile defense system, as well as the trends for their future development.

A line imaging ladar sensor using linear diode laser array and linear avalanche photodiode (APD) array is developed for precise terminal guidance and intelligent proximity fuzing applications. The detection principle of line imaging ladar is discussed in detail, and design method of the line imaging ladar sensor system is given. Taking military tank target as example, simulated tank height and intensity images are obtained by the line imaging ladar simulation system. The subsystems of line imaging ladar sensor including transmitter and receiver are designed. Multi-pulse coherent algorithm and correlation detection method are adopted to improve the SNR of echo and to estimate time-of-flight, respectively. Experiment results show that the power SNR can be improved by N (number of coherent average) times and the maximum range error is 0.25 m. A few of joint transform correlation (JTC) techniques are discussed to improve noncooperative target recognition capability in height image with complex background. Simulation results show that binary JTC, non-zero-order modified fringe-adjusted JTC and non-zero-order amplitude-modulated JTC can improve the target recognition performance effectively.

This paper presents that software radio technique is applied to laser target detection system with the pseudo-random code modulation. Based on the theory of software radio, the basic framework of the system, hardware platform, and the implementation of the software system are detailed. Also, the block diagram of the system, DSP circuit, block diagram of the pseudo-random code generator, and soft flow diagram of signal processing are designed. Experimental results have shown that the application of software radio technique provides a novel method to realize the modularization, miniaturization and intelligence of the laser target detection system, and the upgrade and improvement of the system will become simpler, more convenient, and cheaper.

The standard detecting model of the laser radar is given, and the forms of the detecting model for different detecting conditions are analyzed at first. On the base of foregoing analyses, the detecting range models reflecting the main parameters relationship of the laser detector are set up. On the other hand, the detection probability and the false probability are the important indices of overall design for the laser detector, and they are also the important parameters for appraising the reliability of the laser detector. So the mathematical models reflecting the interaction relationship of the detection probability, the false probability, the single-noise ratio and the detecting threshold value are built at the same time, and the Monte Carlo method is adopted to simulate the statistic distributed rules of the detection probabilities, the false probabilities, the single-noise ratio and the detecting threshold values for the laser detector based on the pulse system and the pseudorandom code system. The simulation results show that the ability of the laser detector using pseudorandom code system is better than that using single pulse system. It is proved by design and experiments that the theoretic foundations are provided by the range models and the simulation results for designing scientifically the laser detector.