Applied Mechanics and Materials Vols. 385-386

Abstract: Diode reverse recovery current dissipation is the most important source of power dissipation for diodes used in fast switching converters or other power devices applications. As the reverse recovery current can peak at very high currents, this may cause the failures of other devices in the circuit. Therefore the Diode Reverse Recovery phenomena should no longer be ignored in device model and circuit simulations employing diodes. Automatic measurement of Diode Reverse Recovery time is becoming essential for mass production industrial process monitoring and device modeling. In this paper, a novel Sagittarius automatic Diode Reverse Recovery Time Measurement System was developed. This system has enabled the automation measurement and improved the measurement speed for about 5-7 times. A new Verilog A Diode Reverse Recovery model which can reflect the actual device characteristics was developed base on the data measured using this new system.

Abstract: Because of its high reliability and stable output, switching power supply is widely used in power electronic systems, but it is can not be ignored that its self-generated electromagnetic has a profound effect on the whole system. In order to suppress conducted interference generated by switching power supply, this article proposed a cascaded technology about the integrated EMI filter, and a simulation is carried out for the power converter output waveform. Experimental results show that this cascaded technology about the integrated EMI filter has a good inhibition on the harmonic.

Abstract: The AGV based on visional route recognition need to deal with problems of random interference of environment and real-time of algorithm. In this paper, an embedded platform based on ARM Cortex-A8 hardware is established, on which an implementation of the optimized algorithm is tested. The first algorithm of route recognition is based on binary spilt and morphology operator, and the second one is based on edge detection operators and Hough transform. The result of the experiment indicates a high performance on anti-interference and real-time.

Abstract: In view of the development of domestic demand for wireless medical technology market, the paper presents a WIFI-based wireless medical monitor which used to collect body temperature, pulse and other physical characteristic parameters of patient in every ward in the building. The entire monitoring system is composed of wireless medical monitors distributed in each ward and monitoring center computer. Wireless medical monitor is developed based on embedded core processor ARM9 and embedded Linux operating system platform, which uses WiFi wireless network to send patient physical characteristic parameters data to the monitoring center computer. Monitoring center computer can be used to view, store, forward recorded patient physical characteristic parameters data, and provides a basis for the patient's next medical programs.

Abstract: G3-PLC, an orthogonal frequency division multiplexing (OFDM) power line communication solution, has recently gained a lot of attention. It supports the application of four types of baseband mapping modes in different environments. These modes typically require a hard-decision demodulation, which will lead to nearly 3dB preference loss. In this paper, we propose an improvement scheme for the baseband mapping modes by changing the constellation encoding method. The optimal soft decision algorithm which makes use of log likelihood ratio (LLR) of the probabilities is used in the demodulators. Simulation results show that the proposed scheme can outperformer many existing algorithms.

Abstract: The differential buses such as RS485 and CAN bus play an important role in industrial control field. In order to make the bus work properly in an extreme environment, this paper proposes a kind of ring topology of bus, by using multiple nodes and redundant method to enhance the reliability of communication of bus. On the other hand, by optimizing the strategy of communication, the efficiency of communication is improved remarkably. And using K/N(G) vote system model to demonstrate the reliability of some methods by calculation. Finally results validate that this new type of ring topology of double circuit with multiple nodes bus possesses good performance in reliability.

Abstract: In this paper, a two-sided tag antenna’s equivalent circuit model and related formulas based on the complex impedance are derived to guide the design and adjustment of a tag antenna’s structure. An ENG-inspired NFRP element is introduced in the design of the tag antenna. A two-sided UHF RFID tag antenna, only 19.2×32×0.7mm³ (0.059×0.098×0.002 λ_0³) in size, is proposed. Its central frequency is 915MHz which can be easily adjusted according to different requirements. The bandwidth of in S₁₁ in -3dB is 10MHz.

Abstract: Based on the virtual instrument technology of the airborne Doppler navigation radar intelligent detection system is introduced, whose Direct Digital Synthesize is designed using Direct Digital Synthesize, producing high resolution Doppler frequency signal through the digital control. The software is written with Visual Basic 6.0, which offer users an intelligent and automatic test environment and test interface. People can easily complete the radar fault detection complete the radar fault detection. The intelligent integrated test system has advanced technology, superior performance, simplicity of operator, strong real-time and convenience of expanding, which has a very important significance to ensure flight safety and improve the fighting capacity.

Abstract: This paper proposes a low power bandgap reference voltage circuit that provides an output reference voltage close to the bandgap voltage having a low output resistance and allows resistive loading. This proposed circuit is design and implemented using the TSMC 0.18μm 1P6M CMOS process. Simulation and measured results verify that the chip size is with power dissipation about 0.1mW, and the operation temperature range formwith temperature coefficient about . The chip supply voltage can from 1.3 to 1.8V with PSRR about 70 dB, and its output reference voltage can stable on .

Abstract: In this paper, a seventh-order elliptic low-pass active-RC filter with three finite transmission zeros is designed for the baseband filter of a 433MHz wireless communication terminal. While designing, the canonical signal flow graph (SFG) method is applied based on component-level simulation of LC ladder prototype circuit. The simulation and measurement results show that the filter satisfied the design specifications.