This thesis presents a circuit architecture to realize clock recovery for fast Ethernet application, including system architecture, modified Mueller Muller algorithm for 100BASE-TX, phase detector for 100BASE-FX and m...
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This thesis presents a circuit architecture to realize clock recovery for fast Ethernet application, including system architecture, modified Mueller Muller algorithm for 100BASE-TX, phase detector for 100BASE-FX and multiple output charge pump PLL. The clock generator circuit with 3.3 V operation voltage has been verified by TSMC 0.35 μm 1P5M CMOS process. The results show that this clock recovery circuit can exactly extract the timing information. It has advantages over other ones for simplicity and easy implementation.
A new technology evaluation of fingerprint verification algorithms has been organized following the approach of the previous FVC2000 and FVC2002 evaluations, with the aim of tracking the quickly evolving state-ofthe- ...
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This paper proposed a morphological erosion operator based on partial differential equation (PDE). Its excellent performances on gradient image, noise removal and edge preserving were demonstrated. Based on this opera...
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This paper proposed a morphological erosion operator based on partial differential equation (PDE). Its excellent performances on gradient image, noise removal and edge preserving were demonstrated. Based on this operator, an evaluating scheme of diffusion coefficients was introduced: the noise and edge of gradient image was controlled and preserved directly by this morphological erosion operator rather than by pre-smoothing input image with Gaussian function or the conventional morphological operator. The new diffusion coefficient had robustness to noise and better localization of edges. Experiments demonstrated that this anisotropic diffusion scheme could efficiently reduce image noise and sharpen the object boundaries.
A contour-based 3D terrain matching method is presented. In the method, Iso-Elevation Contour Map (IECM), a compact feature-based representation is proposed to represent the reference DEM and recovered DEM (REM) from ...
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A contour-based 3D terrain matching method is presented. In the method, Iso-Elevation Contour Map (IECM), a compact feature-based representation is proposed to represent the reference DEM and recovered DEM (REM) from real-time data to convert 3-D terrain matching to contour-based matching. In the contour-based matching, a normalized wavelet descriptor, which is invariant to 2-D rigid transformation and insensitive to noise, is employed to describe contours. A very fast contour-matching algorithm based on normalized wavelet descriptor is presented and the computation cost is analyzed. Control points based on matched contour pairs are located. 2-D rigid image transformation model and parameter estimation using the rule of least root mean square error (RMSE) are discussed. The proposed matching method is robust and computing efficiency is very high, and can obtain high location accuracy;all these are demonstrated by experimental results using real terrain data.
A star map recognition algorithm is proposed. According to the observation accuracy of star sensor, the algorithm eliminates observation error of star triangle before recognition and codes the error-free star triangle...
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A star map recognition algorithm is proposed. According to the observation accuracy of star sensor, the algorithm eliminates observation error of star triangle before recognition and codes the error-free star triangle to form characteristics quantity. The recognition for navigation triangle can only be carried out on the matching of single characteristics quantity. The combination of multi-triangle improves correct recognition ratio. Simulation experiments show that compared with the traditional triangle algorithm, the proposed algorithm has better timeliness and robustness.
The multiple subimage were extracted from the reference image according to a predefined selection method. They were regarded as a template and correlated with the real image. The multiple matching results were integra...
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The multiple subimage were extracted from the reference image according to a predefined selection method. They were regarded as a template and correlated with the real image. The multiple matching results were integrated with the clustering method based on the spatial relation among the subimages. The confidence of the final matching result was given. The test result showed that the method had improved the performance of correlation-based matching.
The common method for image matching is correlation matching. The calculating number was very large when correlation function was used between two matching images. Two steps approach was proposed for image matching th...
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The common method for image matching is correlation matching. The calculating number was very large when correlation function was used between two matching images. Two steps approach was proposed for image matching that was coarse and exact way. Firstly every pixel's gray level was summed up along every column to calculate the mean of column pixels. Then one dimension signal was coarsely matched using one order correlation function. Secondly the points with larger correlation matching values were chosen as the better matching points. These less points were used in the original image as the coordinate origins to calculate the two orders correlation functions. The point with maximum correlation value would be the optimal matching position. Experiences with three kinds of images prove that this approach is faster than conventional one and the matching result is accurate.
Moment invariants are important shape descriptors in computer vision. The method of generating trigonometric function is suggested as a new efficient way to derive various moment invariants. General rule of moment inv...
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Moment invariants are important shape descriptors in computer vision. The method of generating trigonometric function is suggested as a new efficient way to derive various moment invariants. General rule of moment invariant construction is summarized and the notion of moment invariant space is established. Five more moment invariants are derived and tested. Furthermore, general explicit constructions of some high-order moment invariants are developed. The comparisons are made between the stabilities of several invariants for the discrete image. With the help of these additional moment invariants, we can distinguish the image and the object more accurately.
Aiming at the nonlinearity of photoresponse characteristic in infrared focal plane array (IRFPA), an approach for nonuniformity correction in IRFPA was proposed, which is simple and easy to implement by hardware circu...
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Aiming at the nonlinearity of photoresponse characteristic in infrared focal plane array (IRFPA), an approach for nonuniformity correction in IRFPA was proposed, which is simple and easy to implement by hardware circuit. The theoretical analysis and comparison of simulation results show that its performance is more perfect than that of the piecewise linear algorithm and the polynomial fitting algorithm, and only a few correction factors are needed.
This paper proposed a method for generating chaotic key stream based on the chaotic map and a fast algorithm to implement it. This method divides the chaotic attractor into 2n symmetric sub-intervals, samples from the...
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This paper proposed a method for generating chaotic key stream based on the chaotic map and a fast algorithm to implement it. This method divides the chaotic attractor into 2n symmetric sub-intervals, samples from the chaotic orbit every n time intervals, and gets the independently and uniformly distributed 2n-phase key stream. The theoretical and numerical analyses show that the sequence also has a high complexity. This method can be used in fields such as cryptography, numerical simulation and spread spectrum communication, etc.
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