EURASIP Journal on Wireless Communications and Networking

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

List of Papers (Total 2,875)

Position-Based Relaying with Hybrid-ARQ for Efficient Ad Hoc Networking

This paper presents and analyzes an integrated, cross-layer protocol for wireless ad hoc networking that utilizes position location (e.g., through an onboard GPS receiver) and jointly performs the operations of network-layer relaying and link-layer ARQ-based error control. The protocol is a modified version of the hybrid-ARQ-based intra-cluster geographically-informed relaying ...

Dynamic Resource Reservation and Connectivity Tracking to Support Real-Time Communication among Mobile Units

Wireless communication technology is spreading quickly in almost all the information technology areas as a consequence of a gradual enhancement in quality and security of the communication, together with a decrease in the related costs. This facilitates the development of relatively low-cost teams of autonomous (robotic) mobile units that cooperate to achieve a common goal. ...

Optimum Antenna Downtilt Angles for Macrocellular WCDMA Network

The impact of antenna downtilt on the performance of cellular WCDMA network has been studied by using a radio network planning tool. An optimum downtilt angle has been evaluated for numerous practical macrocellular site and antenna configurations for electrical and mechanical antenna downtilt concepts. The aim of this massive simulation campaign was expected to provide an answer to ...

Multihop Medium Access Control for WSNs: An Energy Analysis Model

We present an energy analysis technique applicable to medium access control (MAC) and multihop communications. Furthermore, the technique's application gives insight on using multihop forwarding instead of single-hop communications. Using the technique, we perform an energy analysis of carrier-sense-multiple-access (CSMA-) based MAC protocols with sleeping schemes. Power ...

Throughput Analysis of Fading Sensor Networks with Regular and Random Topologies

We present closed-form expressions of the average link throughput for sensor networks with a slotted ALOHA MAC protocol in Rayleigh fading channels. We compare networks with three regular topologies in terms of throughput, transmit efficiency, and transport capacity. In particular, for square lattice networks, we present a sensitivity analysis of the maximum throughput and the ...

Asymmetric Joint Source-Channel Coding for Correlated Sources with Blind HMM Estimation at the Receiver

We consider the case of two correlated sources, and . The correlation between them has memory, and it is modelled by a hidden Markov chain. The paper studies the problem of reliable communication of the information sent by the source over an additive white Gaussian noise (AWGN) channel when the output of the other source is available as side information at the receiver. We assume ...

Secure, Redundant, and Fully Distributed Key Management Scheme for Mobile Ad Hoc Networks: An Analysis

Security poses a major challenge in ad hoc networks today due to the lack of fixed or organizational infrastructure. This paper proposes a modification to the existing "fully distributed certificate authority" scheme for ad hoc networks. In the proposed modification, redundancy is introduced by allocating more than one share to each node in order to increase the probability of ...

Minimum Energy Decentralized Estimation in a Wireless Sensor Network with Correlated Sensor Noises

Consider the problem of estimating an unknown parameter by a sensor network with a fusion center (FC). Sensor observations are corrupted by additive noises with an arbitrary spatial correlation. Due to bandwidth and energy limitation, each sensor is only able to transmit a finite number of bits to the FC, while the latter must combine the received bits to estimate the unknown ...

Maintaining Differentiated Coverage in Heterogeneous Sensor Networks

Most existing research considers homogeneous sensor networks, which suffer from performance bottleneck and poor scalability. In this paper, we adopt a heterogeneous sensor network model to overcome these problems. Sensing coverage is a fundamental problem in sensor networks and has been well studied over the past years. However, most coverage algorithms only consider the uniform ...

Optimal Throughput and Energy Efficiency for Wireless Sensor Networks: Multiple Access and Multipacket Reception

We investigate two important aspects in sensor network design—the throughput and the energy efficiency. We consider the uplink reachback problem where the receiver is equipped with multiple antennas and linear multiuser detectors. We first assume Rayleigh flat-fading, and analyze two MAC schemes: round-robin and slotted-ALOHA. We optimize the average number of transmissions per ...

Distributed Detection and Fusion in a Large Wireless Sensor Network of Random Size

For a wireless sensor network (WSN) with a random number of sensors, we propose a decision fusion rule that uses the total number of detections reported by local sensors as a statistic for hypothesis testing. We assume that the signal power attenuates as a function of the distance from the target, the number of sensors follows a Poisson distribution, and the locations of sensors ...

Intersymbol Decorrelating Detector for Asynchronous CDMA Networks with Multipath

Most reported multiuser detection techniques for CDMA systems need the channel estimation including the delay spread and the parameters of the multipath channel of the desired user. This paper proposes an intersymbol decorrelating detector that makes use of the cross-correlation matrix constructed by the consecutively received symbols. The proposed detector is attractive for its ...

Software-Defined Radio—Basics and Evolution to Cognitive Radio

We provide a brief overview over the development of software-defined or reconfigurable radio systems. The need for software-defined radios is underlined and the most important notions used for such reconfigurable transceivers are thoroughly defined. The role of standards in radio development is emphasized and the usage of transmission mode parameters in the construction of ...

Extended Lock Range Zero-Crossing Digital Phase-Locked Loop with Time Delay

The input frequency limit of the conventional zero-crossing digital phase-locked loop (ZCDPLL) is due to the operating time of the digital circuitry inside the feedback loop. A solution that has been previously suggested is the introduction of a time delay in the feedback path of the loop to allow the digital circuits to complete their sample processing before the next sample is ...

Adaptive Transmitter Optimization in Multiuser Multiantenna Systems: Theoretical Limits, Effect of Delays, and Performance Enhancements

The advances in programmable and reconfigurable radios have rendered feasible transmitter optimization schemes that can greatly improve the performance of multiple-antenna multiuser systems. Reconfigurable radio platforms are particularly suitable for implementation of transmitter optimization at the base station. We consider the downlink of a wireless system with multiple transmit ...

Towards a Fraud-Prevention Framework for Software Defined Radio Mobile Devices

The superior reconfigurability of software defined radio mobile devices has made it the most promising technology on the wireless network and in the communication industry. Despite several advantages, there are still a lot to discuss regarding security, for instance, the radio configuration data download, storage and installation, user's privacy, and cloning. The objective of this ...

Supporting QoS in MANET by a Fuzzy Priority Scheduler and Performance Analysis with Multicast Routing Protocols

Mobile ad hoc network is an autonomous system of mobile nodes characterized by wireless links. The major challenge in ad hoc networks lies in adapting multicast communication to environments, where mobility is unlimited and failures are frequent. Such problems increase the delays and decrease the throughput. To meet these challenges, to provide QoS, and hence to improve the ...

Flexible Radio: A Framework for Optimized Multimodal Operation via Dynamic Signal Design

The increasing need for multimodal terminals that adjust their configuration on the fly in order to meet the required quality of service (QoS), under various channel/system scenarios, creates the need for flexible architectures that are capable of performing such actions. The paper focuses on the concept of flexible/reconfigurable radio systems and especially on the elements of ...

Multimode Communication Protocols Enabling Reconfigurable Radios

This paper focuses on the realization and application of a generic protocol stack for reconfigurable wireless communication systems. This focus extends the field of software-defined radios which usually concentrates on the physical layer. The generic protocol stack comprises common protocol functionality and behavior which are extended through specific parts of the targeted radio ...

A Reconfigurable Spiral Antenna for Adaptive MIMO Systems

We present a reconfigurable spiral antenna for use in adaptive MIMO systems. The antenna is capable of changing the sense of polarization of the radiated field. It is fabricated by using an RF-MEMS technology compatible with microwave laminate substrates developed within the author's group. The proposed antenna structure is built on a number of rectangular-shaped bent metallic ...

Adaptive Mobile Positioning in WCDMA Networks

We propose a new technique for mobile tracking in wideband code-division multiple-access (WCDMA) systems employing multiple receive antennas. To achieve a high estimation accuracy, the algorithm utilizes the time difference of arrival (TDOA) measurements in the forward link pilot channel, the angle of arrival (AOA) measurements in the reverse-link pilot channel, as well as the ...

New PN Even Balanced Sequences for Spread-Spectrum Systems

A new class of pseudonoise even balanced (PN-EB) binary spreading sequences is derived from existing classical odd-length families of maximum-length sequences, such as those proposed by Gold, by appending or inserting one extra-zero element (chip) to the original sequences. The incentive to generate large families of PN-EB spreading sequences is motivated by analyzing the spreading ...

Modular Software-Defined Radio

In view of the technical and commercial boundary conditions for software-defined radio (SDR), it is suggestive to reconsider the concept anew from an unconventional point of view. The organizational principles of signal processing (rather than the signal processing algorithms themselves) are the main focus of this work on modular software-defined radio. Modularity and flexibility ...