EURASIP Journal on Wireless Communications and Networking

http://link.springer.com/journal/13638

List of Papers (Total 3,021)

An Analysis Framework for Mobility Metrics in Mobile Ad Hoc Networks

Mobile ad hoc networks (MANETs) have inherently dynamic topologies. Under these difficult circumstances, it is essential to have some dependable way of determining the reliability of communication paths. Mobility metrics are well suited to this purpose. Several mobility metrics have been proposed in the literature, including link persistence, link duration, link availability...

Asymptotic Analysis in MIMO MRT/MRC Systems

Through the analysis of the probability density function of the squared largest singular value of a complex Gaussian matrix at the origin and tail, we obtain two asymptotic results related to the multi-input multi-output (MIMO) maximum-ratio-transmission/maximum-ratio-combining (MRT/MRC) systems. One is the asymptotic error performance (in terms of SNR) in a single-user system...

Relay Techniques for MIMO Wireless Networks with Multiple Source and Destination Pairs

A multiple-input multiple-output (MIMO) relay network comprises source, relay, and destination nodes, each of which is equipped with multiple antennas. In a previous work, we proposed a MIMO relay scheme for a relay network with a single source and destination pair in which each of the multiple relay nodes performs QR decompositions of the backward and forward channel matrices in...

Adaptive Rate-Scheduling with Reactive Delay Control for Next Generation CDMA Wireless Mobile Systems

To minimize QoS degradations during nonstationary packet loadings, predictive rate schedulers adapt the operation according to anticipated packet arrival rates deduced via specified estimation algorithm. Existing predictive rate schedulers are developed under the assumption of perfect estimation, which may not be possible in future CDMA-based cellular networks characterized with...

Multiuser Interference Mitigation in Noncoherent UWB Ranging via Nonlinear Filtering

Ranging with energy detectors enables low-cost implementation. However, any interference can be quite detrimental to range accuracy. We develop a method that performs nonlinear filtering on the received signal energy to mitigate multiuser interference (MUI), and we test it over time hopping and direct sequence impulse radio ultra-wideband signals. Simulations conducted over IEEE...

Mutual Image-Based Authentication Framework with JPEG2000 in Wireless Environment

Currently, together with the development of wireless connectivity, the need for a reliable and user-friendly authentication system becomes always more important. New applications, as e-commerce or home banking, require a strong level of protection, allowing for verification of legitimate users' identity and enabling the user to distinguis trusted servers from shadow ones. A novel...

A Power-Efficient Access Point Operation for Infrastructure Basic Service Set in IEEE 802.11 MAC Protocol

Infrastructure-based wireless LAN technology has been widely used in today's personal communication environment. Power efficiency and battery management have been the center of attention in the design of handheld devices with wireless LAN capability. In this paper, a hybrid protocol named improved PCF operation is proposed, which intelligently chooses the access point- (AP...

Cross-Layer Quality-of-Service Analysis and Call Admission Control in the Uplink of CDMA Cellular Networks

This paper addresses cross-layer quality-of-service (QoS) provisioning in the uplink of CDMA cellular mobile networks. Each mobile can take up to four UMTS traffic classes in our model. At the data link layer and the network layer, the QoS performances are defined in terms of signal-to-interference-plus-noise ratio and outage probability, and packet loss rate and delay...

Joint Downlink Power Control and Multicode Receivers for Downlink Transmissions in High Speed UMTS

We propose to combine the gains of a downlink power control and a joint multicode detection, for an HSDPA link. We propose an iterative algorithm that controls both the transmitted code powers and the joint multicode receiver filter coefficients for the high-speed multicode user. At each iteration, the receiver filter coefficients of the multicode user are first updated (in order...

Modeling and Characterization of VCOs with MOS Varactors for RF Transceivers

As more broadband wireless standards are introduced and ratified, the complexity of wireless communication systems increases, which necessitates extra care and vigilance in their design. In this paper, various aspects of popular voltage-controlled oscillators (VCOs) as key components in RF transceivers are discussed. The importance of phase noise of these key blocks in the...

Rate-Optimal Multiuser Scheduling with Reduced Feedback Load and Analysis of Delay Effects

We propose a feedback algorithm for wireless networks that always collects feedback from the user with the best channel conditions and has a significant reduction in feedback load compared to full feedback. The algorithm is based on a carrier-to-noise threshold, and closed-form expressions for the feedback load as well as the threshold value that minimizes the feedback load have...

A New Authentication Protocol for UMTS Mobile Networks

This paper analyzes the authentication and key agreement (AKA) protocol for universal mobile telecommunications system (UMTS) mobile networks, where a new protocol is proposed. In our proposed protocol, the mobile station is responsible for generating of authentication token (AUTN) and random number (RAND). The home location register is responsible for comparison of response and...

Effective Radio Resource Management for Multimedia Broadcast/Multicast Services in UMTS Networks

Broadcast and multicast offer a significant improvement of spectrum utilization, and become particularly important where information channels are shared among several users. Mobile cellular environments are expected to evolve with the technological approaches necessary to facilitate the deployment of multimedia services, such as streaming, file download, and carousel services...

Routing and Power Allocation in Asynchronous Gaussian Multiple-Relay Channels

We investigate the cooperation efficiency of the multiple-relay channel when carrier-level synchronization is not available and all nodes use a decode-forward scheme. We show that by using decode-forward relay signaling, the transmission is effectively interference-free even when all communications share one common physical medium. Furthermore, for any channel realization, we...

Impact of Video Coding on Delay and Jitter in 3G Wireless Video Multicast Services

We present an efficient method for supporting wireless video multicast services. One of the main goals of wireless video multicast services is to provide priority including dedicated bandwidth, controlled jitter (required by some real-time and interactive traffic), and improved loss characteristics. The proposed method is based on storing multiple differently encoded versions of...

On Cross-Layer Design for Streaming Video Delivery in Multiuser Wireless Environments

We exploit the interlayer coupling of a cross-layer design concept for streaming video delivery in a multiuser wireless environment. We propose a cross-layer optimization between application layer, data link layer, and physical layer. Our aim is to optimize the end-to-end quality of the wireless streaming video application as well as efficiently utilizing the wireless resources...

Multiservice Vertical Handoff Decision Algorithms

Future wireless networks must be able to coordinate services within a diverse-network environment. One of the challenging problems for coordination is vertical handoff, which is the decision for a mobile node to handoff between different types of networks. While traditional handoff is based on received signal strength comparisons, vertical handoff must evaluate additional factors...

Key Management for Secure Multicast over IPv6 Wireless Networks

Multicasting is an efficient method for transmission and routing of packets to multiple destinations using fewer network resources. Along with widespread deployment of wireless networks, secure multicast over wireless networks is an important and challenging goal. In this paper, we extend the scope of a recent new key distribution scheme to a security framework that offers a...

Cross-Layer Design and Analysis of Downlink Communications in Cellular CDMA Systems

A cellular CDMA network with voice and data communications is considered. Focusing on the downlink direction, we seek for the overall performance improvement which can be achieved by cross-layer analysis and design, taking physical layer, link layer, network layer, and transport layer into account. We are concerned with the role of each single layer as well as the interaction...

Multiple-Channel Security Architecture and its Implementation over SSL

This paper presents multiple-channel SSL (MC-SSL), an architecture and protocol for protecting client-server communications. In contrast to SSL, which provides a single end-to-end secure channel, MC-SSL enables applications to employ multiple channels, each with its own cipher suite and data-flow direction. Our approach also allows for several partially trusted application...

Optimal and Suboptimal Finger Selection Algorithms for MMSE Rake Receivers in Impulse Radio Ultra-Wideband Systems

The problem of choosing the optimal multipath components to be employed at a minimum mean square error (MMSE) selective Rake receiver is considered for an impulse radio ultra-wideband system. First, the optimal finger selection problem is formulated as an integer programming problem with a nonconvex objective function. Then, the objective function is approximated by a convex...

ZSBT: A Novel Algorithm for Tracing DoS Attackers in MANETs

Denial of service (DoS) attack is a major class of security threats today. They consume resources of remote hosts or network and make them deny or degrade services for legitimate users. Compared with traditional Internet, the resources, such as bandwidth, memory, and battery power, of each node are more limited in mobile ad hoc networks (MANETs). Therefore, nodes in MANETs are...

Energy-Efficient Medium Access Control Protocols for Wireless Sensor Networks

A key challenge for wireless sensor networks is how to extend network lifetime with dynamic power management on energy-constraint sensor nodes. In this paper, we propose two energy-efficient MAC protocols: asynchronous MAC (A-MAC) protocol and asynchronous schedule-based MAC (ASMAC) protocol. A-MAC and ASMAC protocols are attractive due to their suitabilities for multihop...