Earticle

The aim of this paper is to estimate the Channel characteristics of OFDM communication system by using worst case H∞ approach and comparing the result with existing Kalman [6] and H∞ channel estimators [8]. This estimation criterion is different from kalman filter. These two algorithms fail because of more updation parameters like V, W and Q. In order to estimate the signal without updating factors, we are proposing this worst case H-infinity approach in which V and W are considered as worst case values (maximum). In this approach V and W are updated only once for entire recursive estimation process. This method improves the performance even for high data rate also.

Study of different patterns on a local neighborhood of a texture plays an important role in characterization, and classification of the textures. The present paper proposes a method for measuring the occurrence factor of patterns on a randomly thresholded binary image. For this process eight simple patterns are chosen on a 3×3 neighborhood. The simple patterns are chosen in such a way that any complex pattern can be formed by grouping one or more of these simple patterns. The pattern occurrence factor of different binary images is also compared with the actual binary texture image. The experimental results on sixty four textures indicate good comparison of variation of occurrence in these patterns on different binary images of random threshold

The focus of this paper is to develop a Ubiquitous framework which can record the incoming calls and sort them according to the service provider. This information will provide subsequent traffic on a particular network and hence will be useful in deciding the bandwidth allocation. Second part of the paper deals with application of constraint on the ontology using OCL thereby providing a strict check on accessing and filtering of the information.

In order to organize informational security the juridical documents, technical means and cryptographically algorithms, systematic, apparatus-systematic or apparatus-technical means are widely used. And with the advent of high-speed digital lines of information transfer requirements for cryptographic means of enciphering is growing more and more. In cryptosystem based on stream ciphers the entering information is not late in cryptosystem and it allows developing high-speed cryptographic hardware. Besides generated pseudo-casual and truly casual sequences it is widely used in cryptosystems for generation of initial values of confidential parameters and the secret key in the electronic digital signature. The idea of working out of algorithm EDC was developed using operations of algebra parameters. Mathematical model of the digital signature, including parts of formation and the signature check, satisfying to conditions of demanded firmness in a composition of algorithm of enciphering and existing complexities of calculations are developed. In this article also methods of estimation crypto stability of stream cipher algorithm of enciphering and practical results of an estimation of the new developed algorithm are resulted. Also the criteria of protection documentary, vocal and information video in information-communication systems and using cryptographic means are given in this article.

This article dedicated to a review of modern methods of researching and estimation of productivity of IEE 802.11 protocol, based on Markov models and allows effectively estimate main indices of productivity of network functioning. The researches of estimation of network functioning is taking on special significance because of adaptation of IEEE 802.11 standard for network construction on a city and regional scale, that solved the problem of providing data in distant regions. A mathematical model of information transmission processes using radio link discreet channels. This model represents the quality indicators of broadband communication channels. The model helps to generate main quality indicators of super broadband communication channel and to calculate the coverage of broadband access networks in field applications. In article on the basis of the theory of reliable communication and mathematical modeling the comparative analysis of efficiency of communication channels in conditions of the limited by power and by a pass band without and with use of system of channel encoding is made. All calculations and results in detail analyze on the basis of model of a plane “band-efficiency"