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November 30,2012
Volume 5,Issue 22
Pages -
Subject Area:Electronic Technology,Image Processing,Fibre Optical Communication Technology

Title: A compact EMI filter with good high frequency characteristics based on the overlapped and interleaved winding

Authors: DENG Liangyong, HUANG Huifen
PP: 2205-2212
Abstract: The overlapped and interleaved arrangement of two common mode (CM) L-C windings is used to integrate the CM electro-magnetic interference (EMI) filter, and the equivalent parallel capacitance (EPC) is effectively decreased to about 14% of the original EMI filter so that the filter high-frequency performance is improved. The differential mode (DM) capacitors are completed by the capacitances between two overlapped and interleaved windings. Therefore, CM inductors, CM capacitors and DM capacitors can be integrated in the integrated overlapped and interleaved L-C winding mode, and it realizes the filter miniaturization. In addition, flexible foils are rolled around E core side legs to enhance DM inductance. And the turn numbers of flexible foils make the design of DM inductance more controllable and flexible. The integrated EMI filter combined interleaved planar PCB windings and flexible foils in the same ferrite core has not only good high frequency characteristics, but also compact profile. Under the same manufacturing complexity and cost, the effectiveness of these technologies has been confirmed by experiments.
Keywords: electronic technology; electro-magnetic interference filter; overlapped and interleaved windings; parasitic parallel capacitance; flexible foils; differential mode inductance

Title: A new distributed downlink resource allocation algorithm in Femtocell networks

Authors: HAN Bao, LI Xu, MAO Junling, XIE Gang
PP: 2195-2204
Abstract: In order to resolve the problem of interference, a distributed resource allocation algorithm based on cognitive radio technology is proposed which aims to maximize the fairness between all FUEs. Simulation results show that, compared with the algorithm that maximize the system capacity and the algorithm with equal transmitting power, the capacity of our algorithm is only a little smaller than the former and is much bigger than the latter, but our algorithm can fast converge and effectively guarantee the fairness between FUEs.
Keywords: basic disciplines of information science and system science; Femtocell; distributed; channel allocation; power control; fairness

Title: An approach based on curve fitting for channel equalization in SAR-GMTI

Authors: CHEN Shichao, LI Jian, XING Mengdao, BAO Zheng
PP: 2189-2194
Abstract: This paper fouces on the problem of the uncleanness of clutter suppression caused by the differences among different channels of SAR-GMTI, and the fake error of detection and orientation of the moving targets, subsequently. A simple but effective approach using curve fitting in the Doppler domain is proposed to describe the error among different channels. The influence introduced in from the system is greatly eliminated by the proposed method, and the coherent coefficients between channels are improved dramaticlly. Accurate processing is achieved for the detection and orientation of the moving target, due to the cleanness implementation of clutter suppression with calibration channels. The effectiveness of the proposed method is demonstrated with real data.
Keywords: signal and information processing; channel equalization; curve fitting; moving target detection

Title: A new method of quasi-static 3D ultrasound elastography

Authors: XIE Bo, HUANG Qinghua
PP: 2183-2188
Abstract: In this paper, a novel quasi-static 3D ultrasound elastography method based on a low degree of freedom (DoF) linear scanning mode is proposed. A linear slide rail is used to rigidly control the scanning trajectory and by appropriately adjusting the height of the probe, the pre-and post-compression ultrasound radio-frequency data are acquired sequentially. Finally, a 3D quasi-static ultrasound elastography system is developed using a dynamic programming method and 3D strain imaging. Experiments demonstrate that the system can be easily manipulated, and can accurately obtain the 3D strain distribution of an elasticity ultrasound phantom.
Keywords: signal and information processing; medical ultrasound; elastography; quasi-static; 3D

Title: Adaptive image quantization based on human visual characteristics

Authors: MA Jianlin, MA Yide
PP: 2176-2182
Abstract: Combined with the human visual characteristics, this paper describes a method for adaptive image quantization using pulse coupled neural network (PCNN). In the proposed method, a non-uniform quantization approach is used to limit the steps of image quantization rather than uniform quantization. This increases the efficiency of the quantization algorithm. Furthermore, we extract information from an input gray image and attempt to build a direct relation between the dynamic properties of PCNN and the static properties of each input image, and then an automatic parameter setting method for PCNN is applied to make the image quantization algorithm even more intelligent. Finally, the different quantitative images are coded using Huffman coding, and the experimental results show that PCNN can be used to quantize images effectively.
Keywords: signal and information processing; image quantization; human visual characteristics; pulse coupled neural network; Huffman coding

Title: A new construction of Jacket matrix based on finite Abelian group

Authors: ZHOU Huizhu, GUO Ying, LEE Moonho
PP: 2167-2175
Abstract: In this paper, an original construction of Jacket matrix motivated by the element inverse property of the center weighted Hadamard matrix is suggested with suitably chosen characters on finite Abelian group. Based on Fermat’s little theorem, the objective Jacket matrix is obtained. The present matrix is an extension of the conventional Jacket matrices on the Galois field. It is a contribution to a problem of searching for an extended family of Jacket matrices on finite Abelian 25 group. In order to get different patterns of Jacket matrices, the conditions of square and non-square are both discussed. Exploiting the well-known Kronecker product of sparse matrices and the relationship of successively lower-order Jacket matrices, a fast construction approach for large size Jacket matrices is proposed. The result indicates the presented fast algorithm performs quite well at decreasing the computation complexity.
Keywords: information processing technique; Jacket matrix; Hadamard matrix; finite Abelian group; Kronecker product; fast Jacket decomposition algorithm

Title: An intelligent fault diagnosis system of digital printing based on automatic image content analysis

Authors: LI Chuan, SUN Guangyu, YANG Shuo, XU Yi
PP: 2158-2166
Abstract: For application of printing fault diagnosis in digital printing process, this paper presents a software framework of intelligent diagnosis for digital printing failure process using automatic image content analysis. This system considers the whole printing procedure from the scanning front to fault-detection terminal. Regarding printing image quality, this system focuses on providing image blur measurement based on Gabor wavelet transform and recognizing four common printing failure processes based on antomatic image content analysis. The experimental results demonstrate that the proposed system can automatically realize quality assessment of printing images and form a correct diagnosis for the printing failure reasons.
Keywords: information processing technique; printing quality; scanning distortion correction; printing fault diagnosis

Title: Approach for system noise estimation of Kalman filtering

Authors: FU Xinchuan, KUANG Yujun
PP: 2151-2157
Abstract: This paper improves the present method of system noise estimation of Kalman filtering, uses an exponential changing factor to adjust the estimation of system noise. This method avoids the appearance of minus sign in the formulas, so it can guarantee the positive semidefinition of system noise matrix and avoid filtering divergence; and also demonstrates that this method can keep the estimation value around the true value. The simulation results show that the method performs well.
Keywords: information processing technique; Kalman filtering; Sage-Husa adaptive filtering; proportion method; exponent method

Title: Research of iris location method based on wavelet transform modulus maxima theory

Authors: WANG Yong, YANG Ling
PP: 2146-2150
Abstract: Biometric recognition technology based on iris of a human eye has received considerable attentions in the area of science, technology and enterprises due to iris stable, unique, noninvasive features. How to locate iris quickly and precisely is a key technique in iris recognition. The paper described an iris location method based on wavelet transform modulus maxima theory to solve the problem. The method was used to detect iris signature singularity after iris signature extracted was analyzed to locate iris inner boundary. Further, Gauss circle detection operator was introduced to locate iris outer boundary. The experiments show that the iris location method based on wavelet transform modulus maxima theory can find iris boundary in the iris image. It also has high reliability and reduces blindness in search of the original method.
Keywords: image processing; iris feature; iris recognition; wavelet transform modulus maxima; iris location

Title: Effect of common-source transimpedance amplifier on optical receiver front-end

Authors: LIU Na, XIE Sheng
PP: 2141-2145
Abstract: Based on the analysis of common-source transimpedance amplifier with constant-current source and buffer stage, an optical receiver front-end with integrated dual photodiodes was simulated based on Charted 0.35 μm electrically erasable programmable read-only memory (EEPROM) complementang metal oxide semiconductor (CMOS) technology. Simulation results showed that the optical receiver with buffer stage under a supply of 3.3 V has a transimpedance gain of 52.1 dB, a bandwidth of 5.5 GHz, whose gain-bandwidth product is much higher than that of the optical receiver with constant-current source. The eye diagram indicated that this receiver front-end can be used in the optical fiber communication system at 10 Gb/s.
Keywords: optical fiber communication technology; standard complementang metal oxide semiconductor technology; optical receiver; transimpedance amplifier

Title: 885 nm LD resonant pumped Cr,Nd:YAG/KTP intracavity frequency doubled self-Q-switched miniature green laser

Authors: CAO Mengjun, BAI Shengchuang, DONG Jun
PP: 2135-2140
Abstract: In this paper, using 885 nm laser diode (LD) as pump source, resonant pumped Cr, Nd:YAG/KTP intracavity frequency doubled self-Q-switched green laser has been demonstrated for the first time. Average output power of 92 mW was obtained at the absorbed pump power of 3.1 W. Corresponding optical-to-optical efficiency of 3% was achieved. Slope efficiency of 5.8% was measured. Laser pulses with pulse width shorter than 5 ns, repetition rate of 17 kHz and peak power over 1 kW were achieved. As the absorbed pump power increases, the laser pulse trains generated in Cr,Nd:YAG/KTP intracavity frequency doubled self-Q-switched lasers exhibit periodical oscillation.
Keywords: optoelectronics and laser technology; Cr,Nd:YAG crystal; resonant pumping; intracavity frequency doubling; self-Q-switched laser

Title: Terahertz filter and modulator based on metal-semiconductor-metal subwavelength hole array

Authors: FAN Fei, JIANG Ziwei, LIU Zhiqiang, WANG Xianghui, CHANG Shengjiang
PP: 2130-2134
Abstract: The transmission and tuning properties of a cross-shaped subwavelength hole array based on periodic metal-semiconductor-metal (MSM) structures have been investigated in the terahertz regime. We find that the resonance frequency and phase of this device can be actively controlled by the semiconductor injection of the MSM structures, and analyze the physical mechanism of this change. The numerical simulations show that this device acts as a tunable band-pass filter with the central frequency of 0.71-0.96 THz, bandwidth of 100 GHz, a multi operating window intensity modulator, and a phase modulator with a phase modulation depth of 0.88π rad.
Keywords: optoelectronics and laser technology; terahertz; metal subwavelength hole array; surface plasmon; filter; modulator

Title: Path following control of mobile robots with formation constraints

Authors: WANG Yintao
PP: 2124-2129
Abstract: In this paper, we address the problem of designing control laws to force the outputs of mobile robots to follow geometric paths while holding a desired formation pattern. The solution is unfolded in two basic parts. Firstly, a virtual robot is constructed and a path following control law is designed out. This law is based on Lyapunov and backstepping which can drive the virtual robot to the desired path regardless of the temporal speed profile. Another part of the solution is formation maintaining control, which promises the formation be achieved by keeping each robot with a certain relative distance and angle to the virtual reference robot. The evident advantages of the proposed scheme are that only the virtual reference robot’s states needed for each robot, so the communication amount is small. Simulation results illustrate the effectiveness of the proposed method.
Keywords: control theory and control engineering; mobile robot; formation; path following; virtual reference point

Title: Simulation and fabrication of suspended C-MEMS structures based on the diffraction effects

Authors: LONG Hu, LIU Dan, XI Shuang, XU Liangliang, TANG Zirong
PP: 2117-2123
Abstract: This paper proposes a fabrication system to create the suspended three-dimensional (3D) carbon-micro-electro-mechanical systems (C-MEMS) structures. By analysing the fabrication process of C-MEMS structures, we find that proper control of exposure condition such as the air gap between the photomask and photoresist and exposure time can help create suspended structures. We also find that the bake and development condition can consolidate or destroy suspended structure. We built an optical model based on diffraction effects by combining the exposure process and optical theory. The optical model which simulates the transmission of light in lithography can predict the intensity distribution on the surface of the SU-8 photoresist. Using this optical model we can not only explain how the suspended structures appear but also present some manufacturing methods. In exposure process, the key elements in exposure process include the exposure mode, the air gap between the photomask and photoresist, exposure time and the photomask pattern. In the experiment, we find that bake time and development time have a great impact on the suspended structures which can consolidate or destroy suspended structures. By combining the proper control of exposure condition in the guidance of optical theory and some manufacturing methods, we can repeatedly fabricate the suspended 3D C-MEMS structures. It is a kind of method which is from arc supposition to arc verification.
Keywords: semiconductor technology; suspended structures; photolithography; carbon-micro-electro-mechanical systems; diffraction effect

Title: Design of piezoelectric transducer and its array for novel fuze ultrasonic detector

Authors: YANG Jian, CHEN Hejuan, TAN Jvqin, ZHANG Ying, ZHAO Guoku
PP: 2110-2116
Abstract: According to the equivalent circuit of the piezoelectric transducer, its response driving by the pulse signal was studied, and the optimum duty ratio of the actuating signal is 50%. In order to improve the shock resistance and long-term storage ability, the P-51 piezoelectric ceramic material and epoxy insulation board were used to make piezoelectric transducers. The structure of the transducer array, which was assembled with 6 transducers, was optimized, and a new transmit-receive switching circuit was designed. The admittance measuring apparatus of piezoelectric transducer was made, and the transducers’ admittance attributes were measured using the self-made apparatus and the available instruments in the laboratory, such as digitized signal generator and computer. The results showed that increasing of its damping coefficient will shorten the piezoelectric transducer stable time. ultrasonic intensity and maximum directivity index of each transducer are different, the directivity index curve and theory curve are the same.
Keywords: mechatronics; fuze; ultrasonic detecting; ultrasonic transducer; array

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