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The input launch power of an optical source is a very important factor for communication engineers in designing fiber optics communication systems. By increasing the input launch power, the non linear effects like Four wave mixing (FWM), Cross phase modulation (XPM) and Self phase modulation (SFM) also affect the BER (bit error rate) by decreasing the maximum Q. factor (Quality factor). In this work...
Digital watermarking is a means to protect multimedia copyright, and it will be subjected to various attacks. Therefore, the research on the robustness of watermarking algorithm is considered as a hot field. A digital image watermarking algorithm that can resist geometric attacks is proposed based on chaos game representation and normalization. Firstly, the original image is mapped to the geometrically...
Localization of multi-pose human facial features is one of the key issues in face recognition technology. The paper presents an algorithm to achieve the accurate positioning of facial features and the corresponding practical steps to realize it. Firstly, we establish the chrominance component mapping function of the feature points based on the chrominance information of high Cb and low Cr values around...
With the development of wireless frequency monitoring equipment, passive localization of multi-targets has become one of the most popular research hotspots. In this paper, by using the characteristic of multi-sensors passive location based on time difference of arrival (TDOA) and the continuity of TDOA at different times, a TDOA based Data Association and multi-targets passive localization algorithm...
In many applications, wavelets with rational dilation have more expected properties such as orthogonality and interpolation than dilation 2. This paper studied the rational dilation factor p/q orthonormal wavelet bases based on multiresolution analysis, stated that the orthonormal wavelet bases should consist of p−q functions ψ1,ψ2,…,ψp-q in W0 = V1 ⊖ V0 and established a perfect reconstruction condition...
This paper introduces the fundamental knowledge of compressed sensing theory, and analyzes the important reconstruction algorithms such as orthogonal matching pursuit, subspace pursuit, but we should know the sparse degree. The sparsity adaptive matching pursuit algorithm can be terminated by setting the conditions to make adaptive sparse degree. This paper puts forward a modified sparsity adaptive...
Chromatic dispersion also called group velocity dispersion (GVD), is a very serious issue for communication engineers to design a wavelength division multiplexing (WDM) system. The pulse gets broader with increasing length of fiber due to chromatic dispersion and this pulse broadening effect stimulates the adjacent bit periods to overlap which causes inter symbol interference (ISI). The chromatic...
ECG (Electrocardiography) signal is one of important means of clinical diagnosis for heart disease which has great significance in clinical medicine. De-noising is a critical task in the preprocess of ECG signal. This paper proposed a dual thresholding function and a level-dependent threshold estimator by the different thresholds estimated based on wavelet coefficients in different layers. Experiments...
The cardinality balanced multi-target multi-Bernoulli (CBMeMBer) filter is an effective multi-target tracking algorithm proposed recently. This contribution applies the unscented particle framework to the implementation of CBMeMBer filter. Importance sampling density function is extended to a higher dimensional space instead of the original Markov state transition density. By taking the latest measurements...
Distributed radar system is helpful to detect small targets in the space. However, Doppler frequency may not only cause the gain lose after signal compression, but also decrease the accumulation gain of the fusing center. Two methods including match filter banks and Fractional Fourier Transform (FRFT) are investigated to compensate the Doppler frequency of the distributed radar system, and their performances...
A photo-electron detection system with 32 PIN photodiodes in 1D array has been designed and implemented within 16cm width. There are mainly two parts in this system: the photodiode frontend with weak signal modulation and sampling, the signal processing backend with parallel signal processing and data transfer. The weak current signal of 32 PIN photodiodes' output is first amplified for about 104...
Least Square (LS) estimation is a simple but not good enough for localization method which is widely used for target position estimation. The time difference of arrival (TDOA) location based on LS method needs to select a reference sensor to obtain a series of equations. Thus, the measured error of the selected first sensor will certainly influence the location accuracy. In our article, an algorithm...
Animal sonar performance is quite better than man-made sonar system, especially in cluttered environment. The harmonic structure sound produced by big brown bat played an important role in echolocation in forests situation. Bat-like harmonic signal resolution was analyzed by Auto-Wideband Ambiguity Function (WAF). For Hyperbolic Frequency Modulation (HFM) signal, the time-scale resolution was related...
Over the decades, two major methods have been developed to deal with the underdetermined Direction-of-Arrival (DOA) estimation problem where there are more sources than sensors. One is based on the higher-order statistics of the received signals, which needs a plenty number of snapshots to guarantee the estimation accuracy and thus is computational complex. The other relies on the sparsity of sources,...
In the passive localization, the estimate error of sensor position and velocity is inevitable. By the use of the calibration, the sensor position and velocity will be improved, especially, to the Cramer-Rao lower bound (CRLB) under the ideal circumstance. The CRLB for the estimate of sensor position and velocity is derived at beginning. Then the CRLB for the estimate of source is followed. Finally,...
A new soft-value bit-flipping low-density parity-check (LDPC) decoding is proposed based on a simplified reliability ratio based on weighted bit-flipping (RRWBF) algorithm. Moreover, we design a soft-output demapping and soft-decision decoding for the LDPC code in China Mobile Multimedia Broadcasting (CMMB). In addition, the complexity of decoding and the consumption of hardware is reduced effectively...
For decreasing the high computational complexity of Turbo product code in PCM/FM telemetry system, a joint decoding algorithm based on syndrome-based decoding and a correlation operation to substitute for searching the competing codeword was proposed. Simulation results show that the proposed algorithm can effectively reduce the decoding complexity with less coding gain degradation.
Noise is always resident in vibration data collected from rotating machinery and different noise levels may relate to different mechanical conditions. As a result, the noise level can seemingly be exploited to evaluate running conditions of rotating machinery. To this end, this paper examined scaling properties of a white-noise series and its increment series. Consequently, it was found that the increment...
Geometrical features extraction for ship, such as location, attitude angle, length, height, is significant in the military area. This paper presents the concept of imaging plane and puts forward a method for ship geometrical features extraction based on different imaging planes. Simulation results have proved the validity of the proposed method.
Matched filtering for linear frequency modulation (LFM) signal is applied more and more widely, and it is required to increase the performance of matched filtering for LFM signal continuously. Adding window is used to achieve this goal. In this article, five typical window functions are selected to act on LFM signal to discuss the impacts of different window functions on the performance of matched...
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