Digital Cosine Research Articles

Research and Analysis on the Cultivation of Intelligent Transportation Technology Professionals under the Background of Integration of Production and Education

In order to improve the training effect of transportation technology professionals, this paper combines the intelligent digital signal processing method to process the data of the integration of production and education, and explores the training process of transportation technology professionals. In the process of data processing of industry-education fusion, this paper demodulates the nuclear magnetic resonance signal obtained after A/D conversion from the carrier frequency signal and places it at zero frequency. At the same time, this paper realizes the separation of the real part and the imaginary part of the nuclear magnetic resonance signal and constructs the digital sine table and digital cosine table of the carrier reference frequency. In addition, the data output by the ADC is subjected to quadrature detection to become two data signals, which are the in-phase component and the quadrature component. Finally, this paper constructs an intelligent analysis model. The simulation results show that the talent training method of intelligent transportation technology based on the integration of production and education has good effects, which can effectively improve the training effect of transportation technology professionals.

The transform performing algorithm for frequency domain search

The algorithm basic for a rotation invariant method producing frequency transform is offered. The execution is based on a blocked matrixes usage. Each group of blocks consists of four units. Transform calculation direction is different for each block in a group. The transform results have a lot of fragments for which invariance for rotation is present for angles divisible by 90 degrees. This limitation is determined by a data representation rectangular grid. The consideration is based on two-dimensional digital cosine transform, but it could be used for different transform basics and any dimensions. The Hadamard matrix can be considered as such an example. The same algorithm could be used for compressed domain image retrievals based on DCT-processing.

Research in Optical Image Differential Based on Digital Filter

In this paper, we create the optical differential filter displayed on a digital micromirror device which achieving differential operation of image is proposed. We produced the digital cosine composite grating through the computer which replaced the traditional holographic composite grating filter, and transmitted the image of composite grating to the DMD which connected to the computer. This method can produce optical filters quickly, avoiding developing, fusing processing, and can according to the specific requirements of the image to adjust the filter quickly. The method not only can save time, but also can improve the processing accuracy greatly.

A NOVEL APPROACH TO WEAK SIGNAL PROCESSING

A novel effective approach to weak continuous and digital signals processing in communication channels with high noise levels is proposed and investigated. The essence of proposed approach is illustrated by examples of various electronic devices. The conditions which allow obtaining the maximal gain in signal to noise ratio are found. This gain exceeds 50 dB for sensitive amplifier and approximately equals to 30 dB for detector of digital cosine video impulse. It is shown that the proposed approach ensures obtaining a lot more gain in signal to noise ratio compared to existing technical solutions. The considered advantages of the described devices allow employing the proposed approach to effective information processing in communication systems with low operating power.

An Adaptive Steganography of Optical Image using Bit-Planes and Multi-channel Characteristics

We proposed an adaptive steganography of an optical image using bit-planes and multichannel characteristics. The experiment's purpose was to compare the most popular methods used in optical steganography and to examine their advantages and disadvantages. In this paper we describe two digital methods: the first uses less significant bits(LSB) to encode hidden data, and in the other all blocks of <TEX>$n{\times}n$</TEX> pixels are coded by using DCT(Digital Cosine Transformation), and two optical methods: double phase encoding and digital hologram watermarking with double binary phase encoding by using IFTA(Iterative Fourier Transform Algorithm) with phase quantization. Therefore, we investigated the complexity on bit plane and data, similarity insert information into bit planes. As a result, the proposed method increased the insertion capacity and improved the optical image quality as compared to fixing threshold and variable length method.

A new digital filter for phasor computation. I. Theory [power system protection

A new pair of orthogonal filters for power system phasor computation is presented. They have excellent time-frequency characteristics for fault location and measurement. Their impulse responses are obtained applying the inverse Fourier transform to a single-lobe function with a strong stopband. From this process, a new window emerges. Without side lobes, it overcomes the temporal barriers imposed by the rectangular window, implicit in digital Fourier filtering. Its length is not restricted to a multiple of one cycle, and it can be adjusted to cover totally the available samples of the fault, extracting the fundamental component with growing precision. On the other hand, its sampling frequency can be reduced to twice the fundamental frequency. In particular, at this minimum sampling frequency, the digital Cosine filter rejects the even harmonics and the aperiodic component.

Separable two-dimensional recursive digital filters with zero-phase approximation in the passband

A new class of separable two-dimensional IIR filters with zero-phase approximation in the passband is presented. It is based on one-dimensional digital cosine filters employing non-causal allpass structures. Due to design efficiency and row-column decomposition, the implementation offers substantial computational savings.

Comparing the Time-Domain EM Response of 2-D and Elongated 3-D Conductors Excited by a Rectangular Loop Source.

We develop an algorithm for modelling the time-domain EM response of a general 2-D geometry excited by a 3-D source. A frontal solution, isoparametric finite-element method is used to solve for the y-components of the magnetic and electric fields in the frequency-wavenumber (x, ky, z, w) domain where y is the direction of strike. Step response solutions are computed for 31 frequencies over the range 1 Hz to 100 kHz and transformed into the time-domain with a digital cosine filter. The response of a 2-D simple block target in a uniform half-space is compared to 3-D models of similar cross section with strike lengths of 0.5, 1, and 2 km, computed using the compact finite-element method. Further comparisons were made with the results of a 3-D time-stepping finite-difference solution for a block on the boundary of a quarter-space. In both cases the agreement between the 2.5-D and the 3-D results is close at early delay times with the 3-D target response decaying more rapidly than the 2-D target response at later times as expected. Although the late time-amplitudes differ, the profile shapes are very similar indicating that the 2.5-D model is useful for interpreting practical exploration problems.