WIRELESS LOCAL AREA NETWORKS IN A PERSONALIZED EMERGENCY RESCUE MANAGEMENT SYSTEM

Анализируются возможности использования локальных беспроводных сетей широкополосного доступа в системах управления спасением людей в чрезвычайных ситуациях. Рассматриваются методы локализации пользователей, оказавшихся в опасных условиях, а также способы повышения доступности информации о них для передачи в центр управления спасением и уровня информированности самих пользователей о планах центра по их спасению. Предлагается оригинальное решение, позволяющее выполнять локализацию поэлементно, т. е. в помещениях и на отдельных участках области обслуживания системы. Показано, что решение может быть успешно использовано для организации сетевой инфраструктуры объектовой части глобальной экспертной системы, обеспечивающей доступ массового абонента в любое время и в любом месте к услуге индивидуализированного управления спасением абонентов при возникновении чрезвычайной ситуации природного или техногенного происхождения. Представлены методы повышения устойчивости сети, в частности метод построения одноранговой ad-hoc-сети с использованием коммуникаций устройство-устройство. The article analyzes the possibilities of using local wireless broadband access networks in emergency management systems for rescue people. Methods of localization of users in dangerous conditions, ways of increasing the availability of information about them for the rescue control center, as well as the level of awareness of the users themselves about the plans of the center for their rescue are considered. It is proposed the original solution, that allows localization to be performed element by element, i.e. in rooms and certain areas of the system service area. It is shown that the solution can be successfully used to organize the network infrastructure of the facility part of the global expert system, which provides mass subscriber access at any time and in any place to the service of individualized management of the rescue of subscribers in case of natural or man-made disasters. Methods for enhancing network stability are presented, in particular, a method for constructing a peer-to-peer ad-hoc network using device-to-device communications.

Research of electrical characteristics of increased uniformity LAN-cables

Formulation of the problem. At present, symmetric LAN cables are widely used in structured cabling systems (SCS) and fixed broadband access (BBA) networks in the world and in Russia. Practical experience of using LAN cables on real broadband access networks shows that high-quality transmission can only be achieved using high-quality highly uniform cables.Objective. Study of the dependence of the quality of LAN-cables on technological equipment and the quality of materials, which provide increased cable uniformity.Results. Based on the experimental studies carried out with the use of a modern measuring system, the main electrical characteristics of the transmission and the mutual influence of the most popular four-pair LAN-cable of the 5e category of the U/UTP4×2×0.52 type in the frequency range up to 100 MHz are determined. It is shown that to ensure high and stable transmission characteristics and mutual influence, modern technological equipment must be equipped with cable quality parameters automatic control systems and it is necessary to choose reliable suppliers when using domestic production materials.Practical significance. For the effective practical use of LAN cables on fixed broadband access networks and in SCS, it is very important to have high stability of electrical characteristics and their compliance with rather high established standards. This is possible only by ensuring high geometric and structural homogeneity of the structural elements of LAN cables.

Radio over Fiber: An Alternative Broadband Network Technology for IoT

Wireless broadband access networks have been positioning themselves as a good solution for manufacturers and users of IoT (internet of things) devices, due mainly to the high data transfer rate required over terminal devices without restriction of information format. In this work, a review of two Radio over Fiber strategies is presented. Both have excellent performance and even offer the possibility to extend wireless area coverage where mobile networks do not reach, or the 802.11 network presents issues. Radio Frequency over Fiber (RFoF) and intermediate Frequency over Fiber (IFoF) are two transmission strategies compatible with the required new broadband services and both play a key role in the design of the next generation integrated optical–wireless networks, such as 5G and Satcom networks, including on RAU (Remote Antenna Unit) new functionalities to improve their physical dimensions, employing a microelectronic layout over nanometric technologies.

Radio over Fiber: An Alternative Broadband Network Technology for IoT

Wireless broadband access networks have been positioning themselves as a good solution for manufacturers and users of IoT (internet of things) devices, due mainly to the high data transfer rate required over terminal devices without restriction of information format. In this work, a review of two Radio over Fiber strategies is presented. Both have excellent performance and even offer the possibility to extend wireless area coverage where mobile networks do not reach or the 802.11 network presents issues. Radio Frequency over Fiber (RFoF) and intermediate Frequency over Fiber (IFoF) are two transmission strategies compatible with the required new broadband services and both play a key role in the design of the next generation integrated optical–wireless networks, such as 5G and Satcom networks, including on RAU (Remote Antenna Unit) new functionalities to improve their physical dimensions, employing a microelectronic layout over nanometric technologies.

Research of the Electrical Parameters of the Telephone Cable in the Frequency Range Up To 30 MHz

The work is devoted to the research of the electrical parameters of the domestic telephone cables in the frequency range from 1 to 30 MHz. The paper presents the results of the experimental determination of the frequency characteristics of the transmission parameters and the crosstalk of the TPPep 10х2х0,4 and TPPepZ 10х2х0,4 types telephone cables produced by ODESKABEL PJSC. The conformity of the domestic production cables with the requirements for digital subscriber line cables for VDSL2 technology services is determined. According to the results of the measurements, approximation formulas for the frequency dependence of the own attenuation, near end crosstalk and equal level far end crosstalk, which are proposed to be used in the modelling of the transmission systems using VDSL2 technology on the domestic broadband access networks based on these cables, are determined.

A Joint Routing and Channel Assignment Scheme for Hybrid Wireless-Optical Broadband-Access Networks

In this paper, we investigate mechanisms for improving the quality of communications in wireless-optical broadband access networks (WOBAN), which present a promising solution to meet the growing needs for capacity of access networks. This is achieved by using multiple gateways and multi-channel operation along with a routing protocol that effectively reduces the effect of radio interference. We present a joint route and channel assignment scheme with the objective of maximizing the end-to-end probability of success and minimizing the end-to-end delay for all active upstream traffic in the WOBAN. Performance evaluations of the proposed scheme are presented using ns-2 simulations, which show that the proposed scheme improves the network throughput up to three times and reduces the traffic delay by six times in presence of 12 channels and four network interface cards (NICs), compared to a single channel scenario.