Institute of Electron Technology
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Recent Developments in Mobile Cloud Scheduling: State-of-the-Art, Challenges and Perspectives, Journal of Telecommunications and Information Technology, 2013, nr 4
Get PDFCloud computing became recently one of the most popular multi-layer distributed computational and data processing environments with various types of services, distributed data storages and resources. With rapid development of mobile technologies, computational clouds have been transformed into the systems with dynamically changing topology and flexible infrastructure through integration with the mobile devices and mobile users as the whole system nodes and actors. The aim of this paper is to provide a comprehensive study and critical comparative analysis of the recent developments in the Mobile Clouds with a new energy optimization criterion scheduling
Performance Evaluation of the MSMPS Algorithm under Different Distribution Traffic, Journal of Telecommunications and Information Technology, 2013, nr 3
Get PDFIn this paper, the Maximal Size Matching with Permanent Selection (MSMPS) scheduling algorithm and its performance evaluation, under different traffic models, are described. In this article, computer simulation results under nonuniformly, diagonally and lin-diagonally distributed traffic models are presented. The simulations was performed for different switch sizes: 4×4, 8×8 and 16×16. Results for MSMPS algorithm and for other algorithms well known in the literature are discussed. All results are presented for 16×16 switch size but simulation results are representative for other switch sizes. Mean Time Delay and efficiency were compared and considered. It is shown that our algorithm achieve similar performance results like another algorithms, but it does not need any additional calculations. This information causes that MSMPS algorithm can be easily implemented in hardware
High Q-factor Fabry-Perot Microresonator as an Alternative to Microdisk in Electro-Optical Modulator for Microwave-Photonic Receivers, Journal of Telecommunications and Information Technology, 2013, nr 2
Get PDFIn the last decade a new idea has been suggested for receivers of communication systems, namely, in microwave receivers’ architecture. Though superheterodyne radio-frequency receivers are best suited to the needs of contemporary wireless communication, however stray radiation of their local oscillator (heterodyne) interferes with neighboring radio-devices and permits to locate the covert receiver. To overcome this drawback the signal transfer to optical range has been suggested. By this conversion, not only an elimination of receiver’s stray radiation is attained but also vast advantages of photonic signal processing become available. The key element of existing microwave-photonic receivers is electro-optical microdisk modulator. However, its realization is complicated and as an alternative an electro-optical modulator based on high Q-factor Fabry-Perot microresonator is suggested. Comparative analysis of both types of modulators is performed, and advantages of high Q-factor Fabry-Perot microresonator based modulator are highlighted
Mobile Telecommunication Systems Changed the Electronic Communications and ICT Market, Journal of Telecommunications and Information Technology, 2013, nr 2
Get PDFThe paper covers development and importance of mobile (cellular) telecommunication services, which developed during last about 20 years and are currently the most important and profitable telecommunication sector. The development of mobile telecommunications becomes essential factor of economic growth in many countries, especially in developing countries. Currently due to the scientific and technological progress as well as the implementation a new standard known as LTE system, cellular telecommunication becomes the basic element of the modern broadband telecommunication infrastructure and internet services. Growing importance of the mobile systems is also connected with great popularity of new mobile terminals – smartphones and tablets. These terminals together with the technology known as cloud computing changed also the ICT market. The paper relates to the situation in many countries, but mainly to Poland
Projekty badawcze realizowane w Instytucie Łączności. Telekomunikacja i Techniki Informacyjne, 2013, nr 1-2
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Nature of Atmospheric Discharges. Telekomunikacja i Techniki Informacyjne, 2013, nr 1-2
Get PDFThis article presents simplified description of the phenomenon of lightning, with special regard to the cloud-toground discharges, and parameters of standardized lightning electromagnetic pulses. Measures of protection against lightning are pointed out. These parameters and measures are important for proper lightning protection of telecommunication facilities
Improvement of the Performance of Database Access Operations in Cellular Networks, Journal of Telecommunications and Information Technology, 2012, nr 3
Get PDFReducing the traffic volume of location updating is a critical issue for tracking mobile users in a cellular network. Besides, when user x wants to communicate with user y, the location of user y must be extracted from databases. Therefore, one or more databases must be accessed for updating, recording, deleting, and searching. Thus, the most important criterion of a location tracking algorithm is to provide a small database access time. In this paper, we propose a new location tracking scheme, called Virtual Overlap Region with Forwarding Pointer (VF), and compare the number of database accesses required for updating, deleting, and searching operations for the proposed scheme and other approaches proposed for cellular networks. Our VF scheme like Overlap Region scheme reduces the updating information when a user frequently moves in boundaries of LAs. Unlike Overlap Region, the VF can reduce number of database accesses for searching users’ information
Towards an Agent-Based Augmented Cloud, Journal of Telecommunications and Information Technology, 2012, nr 1
Get PDFIn the paper an agent-based framework deployed in hybrid cluster and volunteer computing environment is presented. It utilizes two concepts proposed by the authors: Augmented Cloud and Agent Platform as a Service (AgPaaS). Both concepts are discussed in the context of Cloud Computing as defined by NIST. The key idea of the presented solution is to span the cloud (i.e., computing infrastructure) beyond the data center borders by utilizing web browsers as computational workers. The feasibility of the approach was demonstrated by two prototypes: the first one was based on Java Applets and Adobe Flash, whereas the second one on Microsoft Silverlight. The prototypes were next used to perform simple experiments, mainly related to scalability issues. Selected results from the experiments are discussed in the final part of the paper