Aeu-international Journal of Electronics and Communications 

About: Aeu-international Journal of Electronics and Communications is an academic journal published by Elsevier BV. The journal publishes majorly in the area(s): Antenna (radio) & CMOS. It has an ISSN identifier of 1434-8411. Over the lifetime, 4406 publications have been published receiving 64546 citations. The journal is also known as: AEÜ. Archiv für Elektronik und Übertragungstechnik (1996. Print) & International journal of electronics and communications (Print).

The Hamiltonian formulation of energy conserving physical systems with external ports

Abstract: It is reviewed that network modeling of energy conserving physical systems with external ports leads to an intrinsic Hamiltonian formulation of the dynamics, where the interconnection structure defines the structure matrix of a generalized Poisson bracket. This is illustrated on three examples, i.e., LC-circuits, mechanical systems with constraints, and the externally controlled rigid body. Furthermore it is proved that under an additional assumption the generalized Poisson bracket of an observable port-controlled generalized Hamiltonian system is uniquely determined. Finally, it is shown that the standing assumption of independency of the energy variables can be dispensed by considering Dirac structures and implicit port-controlled generalized Hamiltonian systems.

A 22.5 MHz current-mode KHN-biquad using differential voltage current conveyor and grounded passive elements

Abstract: In this paper, a current-mode (CM) Kerwin–Huelsman–Newcomb (KHN) biquad is proposed. The circuit employs three differential-voltage current conveyors (DVCCs) as active elements together with two capacitors and four resistors as passive elements, which all are grounded. The circuit simultaneously provides the three basic filter functions, namely bandpass (BP), highpass (HP) and lowpass (LP) functions. The notch and allpass (AP) functions can be obtained by connecting appropriate output currents directly without using additional active elements. The output signals are obtained at high output impedance ports, which is important for easy cascading in CM operation. SPICE simulation results are given to verify the theoretical analyses.

Evaluation of Reservation Mechanisms for Optical Burst Switching

Abstract: Summary In this paper, we give an overview and classification of optical burst switching schemes and present burst reservation concepts. The performance of various basic reservation mechanisms proposed in literature is compared. Furthermore, a new analysis is introduced that allows to calculate the loss probabilities of a two-class system based on the reservation mechanism just-enough-time (JET) for arbitrary offsets. Finally, a variety of new results is presented including the dependence of burst loss probabilities on offset, burst length distribution, and interarrival distribution.

A cluster-based routing protocol for wireless sensor networks with nonuniform node distribution

Abstract: Due to the nonuniform node distribution, the energy consumption among nodes are more imbalanced in cluster-based wireless sensor networks. Based on this problem, in this paper, a cluster-based routing protocol for wireless sensor networks with nonuniform node distribution is proposed, which includes an energy-aware clustering algorithm EADC and a cluster-based routing algorithm. EADC uses competition range to construct clusters of even sizes. At the same time, the routing algorithm increases forwarding tasks of the nodes in scarcely covered areas by forcing cluster heads to choose nodes with higher energy and fewer member nodes as their next hops, and finally, achieves load balance among cluster heads. Theoretical analysis and simulation results show that our protocol can balance the energy consumption among nodes and increase the network lifetime significantly.

Robust blind image watermarking scheme based on Redundant Discrete Wavelet Transform and Singular Value Decomposition

Abstract: Copyright protection and proof of ownership are two of the main important applications of the digital image watermarking. The challenges faced by researchers interested in digital image watermarking applications lie in the creation of new algorithms to serve those applications and to be resistant to most types of attacks, especially the geometrical attacks. Robustness, high imperceptibility, security, and large capacity are four essential requirements in any watermarking scheme. This paper presents a new image watermarking scheme based on the Redundant Discrete Wavelet Transform (RDWT) and the Singular Value Decomposition (SVD). The gray scale image watermark was embedded directly in the singular values of the RDWT sub-bands of the host image. The scheme achieved a large capacity due to the redundancy in the RDWT domain and at the same time preserved high imperceptibility due to SVD properties. Embedding the watermarking pixel's values without any modification inside the wavelet coefficient of the host image overcomes the security issue. Furthermore, the experimental results of the proposed scheme showed a high level of robustness not only against the image processing attacks but also against the geometrical attacks which are considered as difficult attacks to resist.