| Semi-active laser guided weapons (SLGWs) are widely used in battle fields for the advantages in high-precision guidance effect, strong anti-jamming capability, and so on. Therefore, electro-optical countermeasure technology of SLGWs becomes gradually the research focus. This dissertation begins with studying the key techniques on electro-optical countermeasures of SLGWs and hardware-in-the-loop (HWIL) simulation system, then detailed in theory and technology studies and analyzes the key techniques of laser encoding, laser decoding, laser active jamming, SLGWs anti-jamming evaluation, and HWIL simulation. A low-cost, structure-simple HWIL simulation system of SLGWs'electro-optical countermeasure is designed and developed. It lays the foundation for the further research of the theory and experiment of HWIL simulation system in SLGWs'electro-optical countermeasure. The main work done in this dissertation reads as follows.1. The characteristic of laser pulse parameters likely encoded in laser guidance is studied. The parameter characteristic, the atmosphere propagation effect and target reflection of laser pulse generated by solid pulsed laser as an emphasis are analyzed theoretically. The all kinds of factors affecting the parameters of laser pulses are syudied in quantity, and the uncertainty of each parameter is obtained. The enegy uncertainty of single pulse is no less than -40dB, the wavelength uncertainty is no more than 1nm, the pulse width uncertainty is no more than 30ns, the pulse interval uncertainty is no more than 1μs, and the uncerstainty of polarization is infinite.2. The theory and technology of laser encoding and decoding in laser guidance are studied and summarized. The current laser codes home and abroad are studied and analyzed with the emphasis on the pseudom code and unique interval pair code of American PIM, and the analyse result indicates that the unique interval pair code is a kind of long-period pseudom pulse interval series. The mathematic analysis methods are used to study and analyze the characteristic of laser guidance code, including the series period, mean, standard deviation, probability distribution function, self-correlation function, difference matrix statistic. By studying the methods and techniques of laser decoding, the matching correlation theory and its realizing ways of hardware and software are provided.3. The performance of laser encoding and decoding in electro-optical countermeasure is studied and analyzed. According to the laser decoding theory, the mathematic models on the anti-jamming performance of laser encoding and decoding are set up, respectively, in the identifying process and locking process. The anti-jamming performance of laser decoding is analyzed with normalizer correlation function and average anti-jamming efficiency in the identifying process, and it draws a conclusion that when the sampling period is shorter and the sampling length is longer, the anti-jamming performance of laser decoding in total hardware way is better. In the locking process, the mathematic models of anti-jamming efficiency are set up, respectively, for the three typical laser jammings including the response jamming, transmitting jamming, and laser jamming of high repeat frequency. Further, the important factors influencing the anti-jamming performance and their effects are deduced. Based on the results of trajectory simulation, a technique of target azimuth correlation using target azimuth error difference is put forth, which improves the probability for laser seeker discriminating the jamming pulse in the time gate.4. A HWIL simulation system of SLGWs'electro-optical countermeasure is designed and developed. This system is low-cost and has a simple structure. It consists of semi-active laser seeker simulator (SALS), laser target designator simulator (LTDS), laser jammer simulator (LJS), the projector of target and scenes (PTS), and the control or management system (CMS). SALS reconstructed with PL-2 seeker has the capabilities of scanning field and propotional guidance, and can simulate all kinds of current gyro-stablized SLGWs in guiding capability. LTDS is mainly constructed by 905nm, high power semiconductor laser, and can generate the pulse width modulation (PWM) code with changeable pulse width between 10 and 1000ns, all sorts of pulse interval modulation (PIM) code with the variable repeat frequency between 0 and 100KHz, and the mixed code. LJS is also chiefly made of 905nm, high power semiconductor laser, and may simulate the three kinds of jamming methods, including response jamming, transmitting jamming, and laser jamming of high repeat frequency up to 100KHz. PTS is made up of three-dimentional scenes generated by OpenGL simulation and projector, and can generate all kinds of typical battle field enviroments. CS is composed of host computer, corresponding net, and the supportable interface generated by relevant software, and may control all the system intelligentily. The system establishment provides an integrated experimental equipment for deeply studying and analyzing the electro-optical countermeasure performance of SLGWs in theory. Based on this equipment, the experimental research of laser jamming of high repeat frequency is developed, and the results are in agreement with the theoretical analysis.
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