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A design on single chip integration of MWNTs/SiO2 thin film humidity sensor and interface circuit based on standard IC process is presented. Humidity sensing unit on chip surface is achieved following 0.5um CMOS layout design rules, which ensures compatibility and reliability of the whole system. Interface circuit with phase sensitive demodulation can detect nF level capacitance and derive a proportional...
In this paper, a novel DCT algorithm is proposed using matrix decomposition. The modified unfolded CORDIC based unified architecture for DCT and IDCT with highly modular is developed. The architecture is modeled with Verilog and implemented on FPGA. Compared to the existed architecture, the proposed one has the merits of high modularity and area efficient. Experimental results based on Altera FPGA...
How to protect the fresh water sources is one of the principal problems in the human society, and obviously the industrial sewerage is the main pollution source. However, some water quality monitoring systems based on WSN have been done; we found that the traditional WSN nods have a disadvantage of short-distance communication among the nods, which limits the application in monitoring the industrial...
This paper adopts single-stage amplifier and exponential gain control circuit to achieve gain variation. The single-stage amplifier uses improved Gilbert to increase the gain and bandwidth, and reduce the power consumption and voltage redundancy. The exponential gain control circuit based on corrected exponential function to approach ideal exponential function, and supply wide control voltage range...
Quartz vibrating gyroscope is a kind of MEMS angular rate sensor with advantages in resolution, stability, reliability, volume, weight and cost. In order to make full use of the virtues of this MEMS sensor, chip integration for the sensor becomes necessary. As the equivalent electrical model for the sensor is a prerequisite for design of its interface ASIC, the equivalent electrical model of quartz...
Panoramic camera's characteristics are large field of view, large field of depth, small volume, light weight and good seismic performance. It is widely used in aerial reconnaissance, topographic mapping and other fields. The ZEMAX software is used to research the panoramic camera lens. The lens system of the ordinary optical materials are discussed and analyzed. To explore the system structure with...
In this paper, we studied the influencing factors of the atmospheric turbulence to the frequency mixing efficiency of Coherent laser communication on the base of the transmission characteristics of the atmospheric channel laser, and discussed the inhibition method of its impact.
Precise cable drive has been widely used in many types of industrial, commercial, aerospace, military, medical and research applications as an alternative to gearbox, belt and pulleys, chains and sprocket and other currently available transmission. Significant advantages of precise cable drive include backlash free, high stiffness, high efficiency, no lubrication etc. Cable wrapping design is one...
Instead of conventional proportional integral (PI) controller, non-linear fuzzy proportional integral (NLFPI) controller is proposed to control an inertially stabilized platform. The strategy is to start with a tuned, conventional PI controller that achieve a certain desired performance, replace it with an equivalent linear fuzzy proportional integral (LFPI) controller, and finally convert the linear...
Patterned sapphire with frustum of a cone shape is designed to grow ZnO nanoflower arrays in this paper. The ZnO nanostructures are grown by two-step approach, including the synthesis of homo-seed layer and the growth of ZnO nanostructures in aqueous solutions at low temperature. The as-prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM). ZnO nanostructures...
In the research of space-borne platform vibration, There are some problems such as modeling complex, bad realtime, long modeling cycle, hard to deployment exists in the traditional simulation method. Combining with the theory of six axis parallel positioning platform and multidiscipline physical modeling and simulation tools Maplesim, adopts the non-causal modeling method to set up a satellite vibration...
Circle polarization shift keying (CPolSK) is a new modulation technique. It uses the state of polarization of an electromagnetic wave carrier as the information bearing parameter. This paper describes a modulation/demodulation method based on CPolSK with balance detection, and verifies its feasibility through theoretical analysis and computer simulation. Studies have shown that the optical system...
There were many ways of modulation in the laser communication system. In order to verify that PolSK modulation was the most suitable technology for space laser communication system, we analyzed the implementation principle of several signal modulation ways in this paper. By combing the theoretical analysis and software simulation, we make an analysis and comparative study through five aspects in the...
Coherent laser communication as a potential technical means on high rate satellites information transmission has become the research focus of world power. Space optical hybrid as a core component of the free space coherent laser communication receiver plays even more important role. In this paper a mathematics model is built, which is strictly deduced from the optical principle of 90 degree space...
With the development of science and technology, and enlargement of the field of application, the requirements for measuring range of laser meter become more and more critical. To solve the problem that short-range measurement capability of certain model of laser meter is limited, the method of defocusing, translation APD and setting the reflector to enhanced the effective detection energy and improve...
In this paper, we complete the analysis of the vibration characteristic of the laser communication platform. On the laser communication platform, vibration effect influences on the overall accuracy and stability largely. In our platform a new vibration simulation system based on ARM is brought. In this system, the random numbers which are generated by ARM are output as a PWM (pulse width modulation)...
Green-A is a kind of color limits for the NVIS compatible component. The spectral feature of this color is neither monochromatic nor broadband but rather lies somewhere between these two cases. In this paper, how to design Green-A color limits directly by spectral parameters is discussed. And the mapping relation of parameters between spectrum and chromaticity is calculated and drawn. The mapping...
From the first generation in 1991 to the current tenth generation, liquid crystal display (LCD) monitor capacity has been expanding rapidly. With its output value increasing intensely in recent years, LCD monitor manufacturing has become a landmark industry in the 21 century [1]. LCD as a complex manufacturing process, the liquid crystal cell gap and the measurement of the amount of liquid drops play...
This paper provide a new method of elevator overspeed measurement. Helium-Neon laser is mounted vertically on the surface of the elevator car. One-dimensional photodiode array(PDA) is installed at the top of the shaft. The laser beam passes through the beam shaping lens for good homogeneity and proper divergence angle. According to the total height of shaft and the divergence angle θ=0.4mrad, the...
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