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In this paper, a broadband flat sheet reflector antenna array with low-sidelobe is designed and analyzed. This antenna array is composed of 12 elements. By optimizing the configurations of the elements and the Power Dividers, a low-sidelobe is achieved in the band of 800∼1350MHz. The measured results indicate that the VSWR of this antenna array is less 2, the gain is more than 15∼17dBi, the sidelobe level is less than −20dB and the characteristic of patterns well in this band, and the comparative bandwidth is more than 51%. It is of great value in some speacial communication systems.

In order to design and manufacture more excellent airborne photoelectric stable turret, a new type of aeronautical material-particulate reinforced aluminum matrix composite (SiC/Al composite) is investigated. Several crucial technologies, such as pressureless infiltration technology, interface reaction controls and plate's welding are systematically studied. Then, using SiC/Al composites, the airborne photoelectric stable turret frame is successfully prepared in density of 2.94 g/ cm3; modulus of elasticity of 213 GPa and thermal expansion coefficient of 7.9×10−6/K. The frame has decreased the maximum deformation by by 60% and increased the fundamental frequency by 65% as compared with those of aluminum alloy materials, respectively as shown by finite element analysis results. Those are confirmed by vibration test furthermore. Therefore, a significant lightening effect is achieved and the thermal control load is also reduced. The test result indicates that the stable accuracy of the system achieves 19.8µrad and the optical-axis parallelism of pay load is 0.1mrad. The research applies the SiC/Al composites to airborne photoelectric platforms, which makes a effective exploration for the new aeronautical material's application.

An optical supporting structure is studied to improve its structure stiffness and reduce the rotate error to meet the requirement of aviation remote sensor. A formula to calculate fundamental frequency is proposed using Rayleigh-Ritz method, and a method of is analyzed. By means of OPTISTRUCT software, the maximum fundamental frequency is converted to object function, the deformation under the gravity and the mass are assigned to state variable, wall thicknesses of the structure are converted to design variables. The analysis and test results indicate that the fundamental frequency of designed optical supporting structure has been improved 37.2 Hz from 96.9 Hz, which guarantee the reliability of the sweep mechanism, and the rotate error is 4.89″, which is satisfied for the rotate accuracy in plunge angle. The method of optimization has a certain instructional significance for the design of supporting structures in aviation remote sensor.

Currently most existing remote controls for consumer electronics use infrared remotes (IR) technology to control devices which Increases the demand for advanced functionality that cannot be supported by existing IR. RF remotes provide new levels of interactivity and convenience for today's digital home when compared to IR remotes. New network protocols: ZigBee RF4CE are helping to make this technology accessible to us. In this paper, we first introduce the architecture and primitives of the ZigBee RF4CE, then present the researches of the Application layer and Network layer respectively. Focusing on the functions of Network layer including: frequency usage service; node initialization service; transmission control service; discovery service; power saving service; pairing service and security service.