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A combining of multiple input multiple output (MIMO) signal processing with orthogonal frequency division multiplexing (OFDM) is regarded as a promising solution the performance enhancement of next generation wireless system. In this paper, we proposed a trellis coded MlMO-OFDM system with a channel estimation algorithm for fast fading time-varying channels. In our system, we put more information...
In high-speed mobile wireless communication system, the side-effect of Doppler frequency shift is obvious. In order to get rid of it, the estimation of Doppler frequency shift is necessary. This paper proposes a new way to estimate the Doppler frequency shift with a new Rician channel model. The simulation results show that the estimate of Doppler frequency shift is more accurate with the proposed...
The hand recognition in biometric security was developed successfully for authentication or identification. In this paper, we propose an original method of contact less biometric recognition combining information from color, texture and form. First of all, the segmentation integrates the skin color components and a form model. Then, the authentication process amalgamates by convolution the geometrical...
In this paper, we introduce a new design criterion and a novel class of unitary signal constellations for differential space-time modulation for multiple-antenna systems over Rayleigh flat-fading channels with unknown fading coefficients. The results of simulation shows that the new codes have significantly better performance than existing cyclic group code, especially at low and moderate SNR. For...
This paper deals with timing acquisition in ultra-wideband communications operating in a dense multipath environment. A novel symbol and frame synchronization algorithm is proposed based on the maximum-likelihood criterion. And it exploits the samples of the received signal to estimate the start of the individual frames with respect to a local reference (frame timing) and the location of the first...
This paper presents the theoretical and simulation results for least square channel estimation in MlMO-OFDM systems based on two types of pilot structure, the block-type pilot and the comb-type pilot. We derive their estimation equations, average mean square error lower bounds and optimum pilot design rules. Simulation results verify the theoretical analysis and show that the comb-type pilot aided...
The conventional GPS receivers provide the least user flexibility. It is necessary to have software GPS receivers for easy implementation, simulation and analysis of algorithms. Additionally, a GPS software receiver is more flexible when it comes to adapting the entire receiver to work on the near future Galileo signals. In this software receiver design, the focus is on the baseband signal processing...
A new algorithm of modulation classification for digital signal is presented. This method combines high-order cumulants with subspace decomposition. Specifically, first the modulated signal is characterized by different order cumulant vectors, then with linear transformation, the cumulant vectors are changed into a group of orthogonal bases of subspace. Finally, using the projection of different signal...
Based on analyzing the relationship between the Karush-Kuhn-Tucker (KKT) conditions of support vector machine and the distribution of the training samples, the possible changes of support vector set after new samples are added to training set was analyzed, and the generalized Karush-Kuhn-Tucker conditions was defined. Based on the classification equivalence between the previous training set and the...
The frame sync word (SW) is very important for burst data communication systems. Commonly used SWs such as m-sequences are not optimized for specific system environments in terms of misdetection (including false alarm and detection failure) probability. In this paper, both upper boundary and lower boundary of misdetection probability of frame synchronization are derived for given length and pattern...
Particle swarm optimization (PSO) algorithm has been developing rapidly and has been applied widely since it was introduced, as it is easily understand and realized. For nonlinear bilevel programming whose leader is a nonlinear function, a hybrid PSO algorithm with a simplex algorithm is presented. So far using PSO to solve the nonlinear bilevel programming problem has not been found in the literature...
Product accumulate (PA) codes are a class of codes with good performance, low complexity, regular structure and flexible rate adaptation, which include PA-I codes and PA-II codes. In this paper the differences between PA-I codes and regular low-density parity-check (LDPC) codes on their error-correcting performances are investigated over AWGN channel. The simulation results show that PA-I codes outperform...
Recognition of electrocardiogram (ECG) is an important area in intensive care. Automatic detection & classification of cardiac arrhythmias is important for diagnosis of cardiac abnormalities. Based on the wavelet transform theory, the wavelet networks have been wildly used for signal representation and classification. In this article, a new adaptive wavelet networks with one perceptron has been...
The existence of different clothing and cluttering backgrounds is the main difficulty for accurate torso detection in still images. This paper presents a novel dominant colors based method to tackle this problem. First, the image is segmented into uniform areas. Then, dominant colors of the torso are adaptively selected using a color probability model. Finally, the torso candidates can be extracted...
With the development of sensors capable of high spatial and spectral resolution, anomaly detection in multispectral imagery has gained more attention recently. However, using single detector meets great limitation due to that many of the conditions and parameters that govern performance are unknown or poorly characterized in an operational setting. Unlike the conventional fusion approaches simply...
This paper proposes a new genetic fuzzy approach, in which the traditional method for generating the initial population and the cross operator are improved. Our new method is tested on classifier fusion problem, and the experimental results show it outperform other classifier combination methods in the classification accuracy
This paper investigates enhancing the performance of support vector machines (SVMs) in the application of synthetic aperture radar (SAR) imagery classification. The approach is to replace the conventional Euclidean distance in the SVM kernel with a new similarity measure that is less sensitive to perturbations. Same-target SAR images show perturbations, in part due to the presence of speckle and in...
In this paper, a novel fusion recognition algorithm of courtesy and legal amounts in handwritten Chinese bank checks is presented. Unlike the other fusion methods based on the independent recognition results of courtesy and legal amount, this proposed fusion algorithm begins with the segmentation of legal amount with the guide of recognition candidates of courtesy amount. And then we fuse the recognition...
Recently, two methods called 2D principle component analysis (2DPCA) and 2D linear discriminant analysis (2DLDA) were proposed to overcome the shortcomings in classical PCA and LDA such as time-consuming and singularity. They were used widely in image representation and recognition. A limitation of 2D methods is that, they only reflect the information between rows of images, while discarding columns...
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