Serwis Infona wykorzystuje pliki cookies (ciasteczka). Są to wartości tekstowe, zapamiętywane przez przeglądarkę na urządzeniu użytkownika. Nasz serwis ma dostęp do tych wartości oraz wykorzystuje je do zapamiętania danych dotyczących użytkownika, takich jak np. ustawienia (typu widok ekranu, wybór języka interfejsu), zapamiętanie zalogowania. Korzystanie z serwisu Infona oznacza zgodę na zapis informacji i ich wykorzystanie dla celów korzytania z serwisu. Więcej informacji można znaleźć w Polityce prywatności oraz Regulaminie serwisu. Zamknięcie tego okienka potwierdza zapoznanie się z informacją o plikach cookies, akceptację polityki prywatności i regulaminu oraz sposobu wykorzystywania plików cookies w serwisie. Możesz zmienić ustawienia obsługi cookies w swojej przeglądarce.
With the increase of Internet services and the intensive development of IP infrastructure, WIMAX technology is revolutionizing the broadband wireless world. This due to the low cost deployment, the high capacity and the large coverage. Quality of Service (QoS) is achieved through the use of five service classes (UGS, ertPS, rtPS, nrtPS, and BE), an Admission Control (AC) mechanism, a traffic policer...
The present work proposes a communication system to ensure Internet connectivity and network transparency to a group of nodes within a vehicle in the heterogeneous wireless networks environment. It organizes routers and hosts located inside a vehicle into a mobile network. Each vehicle is equipped with multiple cares of addresses corresponding to multiple network interfaces. The proposed scheme provides...
This paper presents a problem of queueing theoretic performance modeling and analysis of Orthogonal Frequency Division Multiple Access (OFDMA) under broad-band wireless networks. We consider a single-cell WiMAX environment in which the base station allocates subchannels to the subscriber stations in its coverage area. The subchannels allocated to a subscriber station are shared by multiple connections...
Pricing plays a crucial role in trading any resource or service in the existing Broadband Wireless Access system i.e. WiMAX. Through a proper pricing strategy, a wireless service provider would like to achieve the highest revenue, while the end users would like to achieve the highest satisfaction from service usage. In order to make it feasible, in this paper we propose a tradeoff policy between the...
This paper describes both link budget analysis and field experimental results on a mobile WiMAX system deployed in Azumino city, the city scale of which is corresponding to suburban. Firstly, in this paper, the link budget analysis is performed in order to evaluate the system performance based on propagation distance, delay spread, average BER (Bit Error Rate) under a multipath fading environment,...
Multicast broadcast service (MBS) is one of the important features supported by Mobile WiMAX to efficiently transmit data common to a group of users. As MBS services are usually delay-sensitive applications, the concept of the MBS zone is also introduced to provide better quality of service (QoS) for mobile users. However, the large inter- MBS zone handover delay and frame offsets between adjacent...
To better exploit the spectrum resources a wireless sensor network can be used to assists a secondary cognitive radio network by providing information about the current primary spectrum occupancy. In this paper we study the performance of the secondary network when it is co-located with and having similar cell size as a mobile primary network that uses a cellular reuse pattern with seven frequencies...
Worldwide Interoperability for Microwave Access (WiMAX) is defined by the IEEE 802.16. It is an IP based, wireless broadband access technology. This technology can be implemented in 4th generation wireless technologies, for Metropolitan Area Network (MAN). The IEEE 802.16 standard includes specification for the Medium Access Control (MAC) and Physical (PHY) layers and is designed to provide broadband...
A number of algorithms have been proposed for making vertical handover decisions in heterogeneous wireless networks (HWNs). These algorithms are designed for selecting the most suitable radio access technology (RAT) for just a single handoff call from a multimode terminal, during vertical handovers. Multimode terminals for next generation wireless networks have the capability to simultaneously support...
The main goal of the next generation Internet is to support a wide variety of applications with different Quality-of-Service (QoS) requirements. A multi-service network can be achieved by priority scheduling. When connections setup, packet delay for each priority queue is an important issue for route selection. This paper focuses on the head-of-line (HOL) priority queueing system and provides a simple...
Mobile WiMAX is a broadband technology that is capable of delivering triple play services (voice, data, and video). However, mobility in WiMAX system is still an issue when the mobile station (MS) moves and be handovered between base stations (BSs). This issue can cause unnecessary neighboring BS scanning and association, handover delay, and MAC overhead which may affect real-time applications. In...
To meet the continuously increasing demands and requirements of mobile users, next generation wireless systems are more and more relaying on the coexistence of heterogeneous wireless networks. The objective is to provide any time and anywhere connectivity to users. One of the main challenges in such a heterogeneous environment is mobility management, including network selection and Vertical Handover...
Segmented or data-partitioned H.264/AVC codec video streaming separates-out important information from the compressed bitstream and places it into separate packets. Because of the damaging impact of error bursts on real-time video streams, it has become common to apply application-layer forward error correction (FEC) for transport over broadband wireless access networks, herein IEEE 802.16e. In this...
We analyze the quality of service (QoS) performance of different traffic classes in optical-wireless converged networks when different resource handling mechanisms are used. We show that in order to achieve the optimum QoS performance in the EPON-WiMAX converged network for all traffic classes, a proper combination of a dynamic bandwidth allocation algorithm, an intra ONU-BS (integrated optical network...
In this paper, we propose a scheduling algorithm for mobile WiMAX networks that distributes dynamically the bandwidth among service flows while giving real-time packets more chances to satisfy their QoS requirements. The scheduling in the proposed algorithm is assisted by the subscriber stations, hence requiring two-schedulers, a scheduler at the BS and another one at the SS, where preemption is applied...
In this paper, a cognitive system for link adaptation of Wi-Max physical layer is presented. The proposed cognitive system makes the Wi-Max physical layer adaptive to the wireless channel. It monitors the wireless channel as well as the system performance and then by choosing optimal transmission parameters adapts the physical layer thus maximizing the latter. The cognitive system is based on Support...
IEEE 802.16 standard provides a revolutionary air interface that enables very high data rates over large distances. It incorporates a Quality of Service (QoS) framework to ensure satisfactory transmission of different classes of traffic. However, the actual implementation of QoS mechanisms is not defined in the standard and left out for service providers. One of the five different classes of services...
As content management systems for IPTV reduce the latency between server and mobile device, real-time video streaming can tolerate single negative acknowledgments in the event of packet loss. However, the extent of packet retransmissions can be graduated and this paper proposes a scheme that is adaptive to whether network congestion or wireless channel degradation is most responsible for packet loss...
The increasing demands for multimedia applications with various QoS requirements arouse the interest of researchers in the Fourth-generation wireless networks such as WiMAX. In order to ensure that the QoS requirements of these applications are met, effective scheduling algorithms must be designed. Even though it may be trivial to ensure that the minimum QoS of all service classes is attained, this...
Next Generation Wireless Networks (NGWNs) focus on convergence of different Radio Access Technologies (RATs) providing good Quality of Service (QoS) for applications such as Voice over IP traffic (VoIP) and video streaming. The voice applications over IP networks are growing rapidly due to their increasing popularity and cost. To meet the demand of providing high-quality of VoIP at anytime and from...
Podaj zakres dat dla filtrowania wyświetlonych wyników. Możesz podać datę początkową, końcową lub obie daty. Daty możesz wpisać ręcznie lub wybrać za pomocą kalendarza.