高可靠反射式红外探测开关

本文介绍一种低成本高可靠的近距离红外反射开关,最大作用距离可达1.5～2m,最小作用距离为数cm。可广泛用于工控流水线、全自动水笼头、防盗警戒等场合。电路原理图1为红外探测开关电路。N1～N6为六施密特反相器。N5构成几十Hz的低频振荡,占空比95％。N6组成38kHz的载频振荡、由N5对N6进行调制,N6的输出信号经VT3、VT4放大后驱动红外发射管SE303A向外辐射红外脉冲。调制占空比为5％。

入侵报警系统技术讲座(二):开关型入侵探测器的性能与应用

本文讲述了开关型入侵探测器的组成与分类,微动开关式入侵探测器的工作原理和应用特性,磁性开关式入侵探测器的工作原理、性能指标、主要特点和应用特性,以及压力垫和紧急报警开关应用的简单介绍。

Research on the Strategy of Underwater United Detection Fusion and Communication Using Multi-sensor

In order to solve the distributed detection fusion problem of underwater target detection, when the signal to noise ratio (SNR) of the acoustic channel is low, a new strategy for united detection fusion and communication using multiple sensors was proposed. The performance of detection fusion was studied and compared based on the Neyman-Pearson principle when the binary phase shift keying (BPSK) and on-off keying (OOK) modes were used by the local sensors. The comparative simulation and analysis between the optimal likelihood ratio test and the proposed strategy was completed, and both the theoretical analysis and simulation indicate that using the proposed new strategy could improve the detection performance effectively. In theory, the proposed strategy of united detection fusion and communication is of great significance to the establishment of an underwater target detection system.

支撑光网络发展的Si基光子集成器件的研究进展

本文报道了可用于光网络系统终端OADM和OXC的Si基长波长量子阱窄带响应光电接收器、MOEMS和F-P TO宽频域光学滤波器、M-Z型 TO光开关和MMI多路分束器以及可变光强衰减器.用应变层SiGe/Si MQW研制的RCE光电接收器响应谱半宽FWHM<6nm,外量子效率η>4.2%;采用表面微机械加工的桥式光学滤波器,当外加电压0→50V,连续可调谐范围达90nm;彩全平面工艺研制的F-P腔TO滤波器,当外加电流0→57mA时,连续可调谐范围达23nm,FWHM<0.5nm.在SOI Si基片上研制的M-Z TO波导光开关,开关时间<30μs,功耗～100mW.开关消光比为-13dB和-10dB,1×4MMI多路分束器输出光声的不均衡性<0.36dB,总插入损耗为6.9dB.用背向对接的MMI构成的M-Z干涉仪实现了光强的可变调最大衰减量26dB,响应时间为100μs,插入损耗为4.8～7dB.