28940488
Wavelt Transform Application of Video Coding at Very Low Bit Rate
28062426
Radar Detection of Minimum Altitude Flying Targets Based on Wavelet Transforms
44936054
A bandpass sigma-delta modulator employing micro-mechanical resonator
A new second-order bandpass sigma-delta modulator employing a micro-mechanical resonator is presented. The micro-mechanical resonator is used to replace its electronic counterpart for its high Q value. The design is based on the pulse-invariant transform and multi-feedback technique. A compensation circuit is proposed to cancel the anti-resonance in the micro-mechanical resonator in order to obtain the desired transfer function. The modulator is implemented in a 0.6 /spl mu/m CMOS process with an external clamped-clamped beam micro-mechanical resonator. Simulations show that a 47 dB dynamic range can be achieved in a 200 kHz bandwidth centered at 8 MHz when sampled at 32 MHz.
13369239
On Solving the Inverse Scattering Problem with RBF Neural Networks: Noise-Free Case
Neural networks are successfully used to determine small particle properties from knowledge of the scattered light – an inverse light scattering problem. This type of problem is inherently difficult to solve as it is represented by a highly ill-posed function mapping. This paper presents a technique that solves the inverse light scattering problem for spheres using Radial Basis Function (RBF) neural networks. A two-stage network architecture is arranged to enhance network approximation capability. In addition, a new approach to computing basis function parameters with respect to the inverse scattering problem is demonstrated. The technique is evaluated for noise-free data through simulations, in which a minimum 99.06% approximation accuracy is achieved. A comparison is made between the least square and the orthogonal least square training methods.
33971177
Using stereo geometry towards accurate 3D reconstruction
This paper addresses the problem of threedimensional reconstruction and how the geometry of the stereo vision system affects the quality of such a reconstruction. We have considered the general case of non calibrated cameras with approximately known intrinsic parameters. The latter could be known either from previous experiments or from the manufacturer's specifications. In particular, the paper aims at finding the best geometric configuration of the stereo vision system(rotation and translation between the two cameras) that is the least sensitive to errors on the intrinsic parameters. Given that in most cases, in robotics for instance, we have the freedom to set-up the geometry of the stereo vision system, finding how cameras' geometry interacts with errors from different sources is a central issue. Furthermore, when the intrinsic parameters are completely unknown, we have used a single constraint from the scene that has allowed us to calculate the focal length and therefore, the Euclidean reconstruction. We have used extensive simulations where the stereo vision geometry has ranged from pure translation to general 3D motion. The obtained results have clearly shown that a pure translation is always better, as it is not significantly affected by errors on the intrinsic parameters. When assuming that the intrinsic parameters are not known, the use of the perpendicularity constraint from the scene has made it possible to avoid the classical and tedious calibration process.
8322734
Good equidistant codes constructed from certain combinatorial designs
An (n,M,d;q) code is called equidistant code if the Hamming distance between any two codewords is d. It was proved that for any equidistant (n,M,d;q) code, d=
3937587
DC Coefficients Recovery-based Error Concealment Technique for Mpeg-2 Video Streams