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Constantine A. Balanis

Bio: Constantine A. Balanis is an academic researcher from Arizona State University. The author has contributed to research in topics: Antenna (radio) & Radiation pattern. The author has an hindex of 44, co-authored 402 publications receiving 30247 citations. Previous affiliations of Constantine A. Balanis include Arizona's Public Universities & Langley Research Center.


Papers
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Proceedings ArticleDOI
23 May 1983
TL;DR: An algorithm which is used widely to reconstruct geophysical profiles, from remote sensed measurements, is the Algebraic Reconstruction Technique (ART), which is basically an iterative method whose successive profiles are based upon those derived in previous iterations.
Abstract: An algorithm which is used widely to reconstruct geophysical profiles, from remote sensed measurements, is the Algebraic Reconstruction Technique (ART) [ l ] [2]. In addition, the ART has also servea as a prominent method for reconstruction of images in medical applications. The ART is basically an iterative method whose successive profiles are based upon those derived in previous iterations. In applying the ART, the scanned environment is subdivided into cells (usually of rectangular shape) whereby the electrical properties o f the medium within a given cell are assumed to be constant. The iteration process progresses by operating on all the cells in a given path before proceeding to
Proceedings ArticleDOI
07 Mar 2011
TL;DR: In this paper, it was shown that the known stochastic fading models, Rayleigh and Rician, can be obtained by treating multipath deterministically, that is, by solving the electromagnetic scattering problem.
Abstract: Multipath modeling is presented using infinitely long cylinders. It is shown that the known stochastic fading models, Rayleigh and Rician, can be obtained by treating multipath deterministically, that is, by solving the electromagnetic scattering problem.
Proceedings ArticleDOI
06 Jul 2014
TL;DR: In this article, an exact closed-form solution is obtained to evaluate a known integral representation of the Maliuzhinets function for the diffraction problem of waves by a wedge with different face impedances.
Abstract: The Maliuzhinets function (MF) has been used for the diffraction problem of waves by a wedge with different face impedances. For a wedge with arbitrary angle, the Maliuzhinets function is cumbersome to compute which is a major limitation to the use of rigorous theory of diffraction in electromagnetic scattering by a wedge with impedance faces. In this work, an exact closed-form solution is obtained to evaluate a known integral representation of the MF. The tanh - sinh quadrature rule is employed to successfully calculate the integral in the Maliuzhinets function, and the highly accurate numerical computation for Ψn(z) is obtained over the entire complex z plane and for all n. For special wedge angles, the exact formulation is numerically verified by comparing it with the results obtained by numerical integration of the Maliuzhinets function.

Cited by
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Journal ArticleDOI
TL;DR: The gains in multiuser systems are even more impressive, because such systems offer the possibility to transmit simultaneously to several users and the flexibility to select what users to schedule for reception at any given point in time.
Abstract: Multiple-input multiple-output (MIMO) technology is maturing and is being incorporated into emerging wireless broadband standards like long-term evolution (LTE) [1]. For example, the LTE standard allows for up to eight antenna ports at the base station. Basically, the more antennas the transmitter/receiver is equipped with, and the more degrees of freedom that the propagation channel can provide, the better the performance in terms of data rate or link reliability. More precisely, on a quasi static channel where a code word spans across only one time and frequency coherence interval, the reliability of a point-to-point MIMO link scales according to Prob(link outage) ` SNR-ntnr where nt and nr are the numbers of transmit and receive antennas, respectively, and signal-to-noise ratio is denoted by SNR. On a channel that varies rapidly as a function of time and frequency, and where circumstances permit coding across many channel coherence intervals, the achievable rate scales as min(nt, nr) log(1 + SNR). The gains in multiuser systems are even more impressive, because such systems offer the possibility to transmit simultaneously to several users and the flexibility to select what users to schedule for reception at any given point in time [2].

5,158 citations

Journal ArticleDOI
TL;DR: In this paper, a new type of metallic structure has been developed that is characterized by having high surface impedance, which is analogous to a corrugated metal surface in which the corrugations have been folded up into lumped-circuit elements and distributed in a two-dimensional lattice.
Abstract: A new type of metallic electromagnetic structure has been developed that is characterized by having high surface impedance. Although it is made of continuous metal, and conducts dc currents, it does not conduct ac currents within a forbidden frequency band. Unlike normal conductors, this new surface does not support propagating surface waves, and its image currents are not phase reversed. The geometry is analogous to a corrugated metal surface in which the corrugations have been folded up into lumped-circuit elements, and distributed in a two-dimensional lattice. The surface can be described using solid-state band theory concepts, even though the periodicity is much less than the free-space wavelength. This unique material is applicable to a variety of electromagnetic problems, including new kinds of low-profile antennas.

4,264 citations

Journal ArticleDOI
TL;DR: This paper presents a detailed study on recent advances and open research issues in WMNs, followed by discussing the critical factors influencing protocol design and exploring the state-of-the-art protocols for WMNs.

4,205 citations

Journal ArticleDOI
TL;DR: Very large MIMO as mentioned in this paper is a new research field both in communication theory, propagation, and electronics and represents a paradigm shift in the way of thinking both with regards to theory, systems and implementation.
Abstract: This paper surveys recent advances in the area of very large MIMO systems. With very large MIMO, we think of systems that use antenna arrays with an order of magnitude more elements than in systems being built today, say a hundred antennas or more. Very large MIMO entails an unprecedented number of antennas simultaneously serving a much smaller number of terminals. The disparity in number emerges as a desirable operating condition and a practical one as well. The number of terminals that can be simultaneously served is limited, not by the number of antennas, but rather by our inability to acquire channel-state information for an unlimited number of terminals. Larger numbers of terminals can always be accommodated by combining very large MIMO technology with conventional time- and frequency-division multiplexing via OFDM. Very large MIMO arrays is a new research field both in communication theory, propagation, and electronics and represents a paradigm shift in the way of thinking both with regards to theory, systems and implementation. The ultimate vision of very large MIMO systems is that the antenna array would consist of small active antenna units, plugged into an (optical) fieldbus.

2,717 citations

Journal ArticleDOI
Zhouyue Pi1, Farooq Khan1
TL;DR: This article introduces a millimeter-wave mobile broadband (MMB) system as a candidate next generation mobile communication system and demonstrates the feasibility for MMB to achieve gigabit-per-second data rates at a distance up to 1 km in an urban mobile environment.
Abstract: Almost all mobile communication systems today use spectrum in the range of 300 MHz-3 GHz. In this article, we reason why the wireless community should start looking at the 3-300 GHz spectrum for mobile broadband applications. We discuss propagation and device technology challenges associated with this band as well as its unique advantages for mobile communication. We introduce a millimeter-wave mobile broadband (MMB) system as a candidate next generation mobile communication system. We demonstrate the feasibility for MMB to achieve gigabit-per-second data rates at a distance up to 1 km in an urban mobile environment. A few key concepts in MMB network architecture such as the MMB base station grid, MMB interBS backhaul link, and a hybrid MMB + 4G system are described. We also discuss beamforming techniques and the frame structure of the MMB air interface.

2,487 citations