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Utility function recently has been adopted in network studies to describe quality of service. However, the existing utility functions focus only on the effect of power or throughput, so are not suitable to delay and disruption tolerant networking (DTN), where delay and disruption have major impacts on the utility and cannot be ignored. This paper proposes a corresponding sigmoid utility function,...
We carry out a comprehensive analysis of a range of wireless network efficiency considerations. Firstly, we explore the properties and the implications of the power-versus bandwidth-efficiency criteria. Secondly, we perform a detailed top-down analysis of a typical commercial wireless network, which emphasizes the inherent differences between the aforementioned two efficiency metrics, while demonstrating...
In this paper we investigate a cooperative mobile network with respect to error performance. Power allocation is applied between source and relay. The relay cooperates after having received a request from the destination which decides upon successful or non-successful transmission based on a threshold criterion. We show that with respect to the relay's location a suitable power allocation technique...
In this paper, we analyze the advantages of multi-access (MA) systems in heterogeneous networks, where a mobile station (MS) can simultaneously access different non-interfering networks with different radio access technologies (RATs). For this analysis, we consider the following problem: How many RATs should the MS connect to? First, the beneficial aspects of MA is demonstrated by a simplified example,...
The mobile WiMax system is based on IEEE 802.16e, which defines radio interface supporting several classes of Internet Protocol applications and services. While the mobile WiMax system is being deployed, IEEE 802.16m TG is developing an amendment to the IEEE 802.16e to greatly improve the system performance, and it is focusing not only on the PHY and MAC performance but also on a level of end-to-end...
This paper focuses on concurrent real-time multimedia group communication in wireless environment and proposes a video conferencing system to support multiparty streaming video communication on mobile devices. The proposed solution extends session initiation protocol (SIP) to support multicast session negotiation and uses mobile multicast in IP layer for media data distribution. Since wireless network...
Mobile IPTV is a technology that enables users to transmit and receive multimedia traffic anywhere and anytime, using any device. However, in a wireless environment, the network capacity often does not reliably support high-quality high-bandwidth IPTV service traffic. In this paper, a novel resource allocation scheme for Qos-guaranteed mobile IPTV that considers the TV viewing behavior of the user...
Indoor wireless communication systems have been developed to improve cell coverage and throughput with low cost in indoor environment. Among several indoor wireless communication systems such as mobile WiMAX (worldwide interoperability for microwave access) system, WPAN (wireless personal area network) and WLAN (wireless local area network), the mobile WiMAX is one of the promising next-generation...
A mobile node in a MANET must be assigned with a free IP address before it may participate in unicast communications. This is a fundamental and difficult problem in the practical application of any MANET. There have been several solutions proposed, among which prophet address allocation outperforms others in terms of communication overhead, latency, and scalability. However, none of the approaches...
The development of reconfigurable and multimode terminals enable service providers to use the excess bandwidth to support services from other networks, at the expense of terminals performing vertical handover when a call is served by another network. The improvement in the performance of such an overlay heterogeneous network is expressed in terms of the increase in capacity while fulfilling each networkspsila...
Wireless communications and navigation have different constraints to cope with. On the one hand, communication systems traditionally aim at high spectral efficiency with specific requirements such as low latency and low power consumption. On the other hand, navigation is usually based on the transmission of known data signals at low data rates with fine synchronization capabilities for efficient signal...
Most important frameworks supporting mobile communications are not capable of meeting real-time application requirements due to the service degradation appearing during the handover process. This degradation is noticed by the application as an excessive service blocking time and a non-negligible packet loss rate. The reasons of this degradation are: slow procedures for address allocation, too much...
In this paper we study the traditional resource allocation model in IEEE802.16e (mobile WiMax) and propose two algorithms for scheduling and mapping higher layer data into the basic resource allocation units (slots) of OFDMA frames in IEEE802.16e. Both scheduling and mapping approaches are based on the quality of service requirements of each service flow in terms of data rate and bit error rate (BER)...
Any single type of existing wireless and mobile network cannot provide all types of services, e.g., wide coverage and high bandwidth. An integrated wireless and mobile network is introduced by combining different types of networks to provide more comprehensive services. Although an integrated wireless and mobile network provides more connection options for mobile users than a single wireless and mobile...
This paper explores the attributes, layering models and objective functions in cross layer designs for mobile ad hoc wireless networks by taking all the statistical characteristics and constraints from the physical (PHY) layer, media access control (MAC) layer and network (NET) layer into consideration. This paper reviews the entire network optimization across all the PHY/MAC/NET layers. At the PHY...
In this paper, we propose a cognitive radio-based multi-user resource allocation framework for mobile ad hoc networks using multi-carrier DS CDMA modulation over a frequency-selective fading channel. In particular, given pre-existing communications in the spectrum where the system is operating, in addition to potential narrow-band interference, a channel sensing and estimation mechanism is provided...
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