In the design of the photoelectric tracking equipment, to realize the connection between the fiber that rotates with the tracker and the fiber that fixed in the non-rotating vertical axis, The fiber optic rotary joint (FORJ) technology has been applied, which makes the optical signal be transmitted correctly under the fiber rotating status. The normal method that applying the double-channel FORJ has been introduced, based on which, a method applying single-channel FORJ and double-direction optical module has been carried out to improve the transmission quality and simplify the design structure. The insertion loss of the applied FORJ is less than 2dB and the maximum rotary speed can be up to 1000rpm. Meanwhile the design of the optic channel realizes the double-direction signal transmission with rotating movement in single route fiber. The real work shows that the signal of the equipment can be transmitted correctly.

Radar signal detection theory is significant for the radar signal detection, and there are many radar signal detection method at present. In this paper, higher order statistics was used to achieve the radar signal detection. It analyzed the basic theory of higher order statistics and higher order statistics in radar signal detection. And it achieved radar signal detection in the MATLAB software, colored Gaussian noise signal detection method based on dual-spectrum was used to detect the radar signal mixed with man-made noise.

Transparent ZnO gel was synthesized by sol-gel process. In order to getting fine powder of ZnO, at the beginning, ZnO gel was disposed with the pre-firing at 300°C. And then, ZnO powder was calcined at different temperature of 500 °C, 700 °C and 900 °C, the grain size of ZnO powder was different. This paper reports the sensitivity of ZnO gas sensor to three volatile organic compound (VOC) gases (acetone, ethanol and toluene). As we all know, these VOC gases are deleterious to global environment and our health. For different VOC gases, the optimum operating currents and the corresponding sensitivities were different. This paper also researched a nicely sensitive indirect- heating type thick film ZnO gas sensor by adding TiO2. TiO2 was mixed in weight percentage of 2%. The compound oxide sensor debased the optimum working currents of ethanol and toluene. And this sensor also showed rapid response-recovery time, which was propitious to practicability of ZnO gas sensor.

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In order to determine the electromagnetic compatibility between radars better, this paper deduced the distribution character of signal+ noise+ jamming and the signal passing narrowband linear filtering system based on the signal detection theory, and established the quantitative relationship of the radar detection probability and jamming noise ratio on this basis, the detection probability was used to judge the electromagnetic compatibility between radars directly. The simulation experimental results showed that the detection probability was reduced with the increase of interference intensity, when the interference power exceeded the threshold of 1.7 dB, radar detection probability dropped to 50%.