Radio frequency (RF) energy transfer and harvesting techniques have recently become alternative methods to power the next-generation wireless networks As this emerging technology enables proactive energy replenishment of wireless devices, it is advantageous in supporting applications with quality-of-service requirements In this paper, we present a comprehensive literature review on the research progresses in wireless networks with RF energy harvesting capability, which is referred to as RF energy harvesting networks (RF-EHNs) First, we present an overview of the RF-EHNs including system architecture, RF energy harvesting techniques, and existing applications Then, we present the background in circuit design as well as the state-of-the-art circuitry implementations and review the communication protocols specially designed for RF-EHNs We also explore various key design issues in the development of RF-EHNs according to the network types, ie, single-hop networks, multiantenna networks, relay networks, and cognitive radio networks Finally, we envision some open research directions

Wireless Networks With RF Energy Harvesting: A Contemporary Survey

Look to this new, cutting-edge microstrip antenna book for the first exhaustive coverage of broadband techniques, including the most up-to-date information to help you choose and design the optimum broadband microstrip antenna configurations for your applications, without sacrificing other antenna parameters. The book shows you how to take advantage of the lightweight, low volume benefits of these antennas, by providing clear explanations of the various configurations and simple design equations that help you analyze and design microstrip antennas with speed and confidence. This practical resource offers you a comprehensive understanding of the radiation mechanism and characteristic of microstrip antennas, and provides guidance in designing new types of planar monopole antennas with multi-octave bandwidth. You learn how to select and design proper broadband microstrip antenna configurations for compact, tunable, dual-band and circular polarization applications. Moreover, the book compares all the broadband techniques and suggests the most attractive configuration. Extensively referenced with over 300 illustrations and 140 equations.

Broadband Microstrip Antennas

This paper presents a novel single-patch wide-band microstrip antenna: the E-shaped patch antenna. Two parallel slots are incorporated into the patch of a microstrip antenna to expand it bandwidth. The wide-band mechanism is explored by investigating the behavior of the currents on the patch. The slot length, width, and position are optimized to achieve a wide bandwidth. The validity of the design concept is demonstrated by two examples with 21.2% and 32.3% bandwidths. Finally, a 30.3% E-shaped patch antenna, resonating at wireless communication frequencies of 1.9 and 2.4 GHz, is designed, fabricated and measured. The radiation pattern and directivity are also presented.

Wide-band E-shaped patch antennas for wireless communications

This paper presents a study of a novel monopole antenna for ultrawide-band (UWB) applications. Printed on a dielectric substrate and fed by a 50 /spl Omega/ microstrip line, a planar circular disc monopole has been demonstrated to provide an ultra wide 10 dB return loss bandwidth with satisfactory radiation properties. The parameters which affect the performance of the antenna in terms of its frequency domain characteristics are investigated. A good agreement is achieved between the simulation and the experiment. In addition, the time domain performance of the proposed antenna is also evaluated in simulations.

Study of a printed circular disc monopole antenna for UWB systems

Review on the criteria anticipated for the fabrication of highly efficient ZnO-based visible-light-driven photocatalysts

Evaluation of Municipal Solid Waste Management Scenarios using Multi-Criteria Decision Making under Fuzzy Environment

A high-gain circularly polarized microstrip antenna array is proposed using space-fed configuration. In planar arrays, the design of feed network to generate circular polarization becomes extremely complex. The proposed configuration eliminates the feed network, which gives high efficiency and gain. Simulated and measured results are presented. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2221–2223, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25451

Circularly polarized space-fed microstrip antenna arrays

Given a network topology and costs associated with the links, the problem of generating a minimum cost multicast tree can be modelled as a Steiner tree problem However, many real time applications such as video-conferencing require that data be sent within prespecified delay limits in order to avoid problems such as anachronism and lack of synchronization This paper deals with the delay-bounded cost-optimal multicast tree (DBCMT) generation problem A closely related problem is to find a delay-bounded cost-optimal path (DBCP) between a specified source and destination node Such a path can be used be used as a starting point to solve the DBCMT We present here two heuristics for building delay constrained multicast trees which have near optimal cost A comparison of our heuristics with other proposed heuristics is also presented

Efficient Algorithms for Delay Bounded Multicast Tree Generation for Multimedia Applications

Several microstrip antenna (MSA) configurations are available to generate the circular polarization (CP), which can be obtained by either single feed or dual feed. Square or circular MSA fed at two orthogonal points with equal amplitude and 90/spl deg/ phase difference yields wider axial ratio bandwidth than the single feed MSA, but the VSWR bandwidth is small. In this paper, several stacked MSA configurations using either square or circular patches have been proposed to increase both the axial ratio and VSWR bandwidths with higher directivity. Only one patch at the bottom layer is fed at two orthogonal points with equal amplitude and 90/spl deg/ phase difference, and the other parasitic square or circular patches are stacked to yield broadband CP. These antennas have been analyzed using the IE3D software based on the method of moments.

Stacked microstrip antennas for broadband circular polarization

Compact gap-coupled shorted 90° sectoral microstrip antennas (MSAs) have been proposed, whose bandwidth is 2.5 times the bandwidth of the corresponding circular MSA (CMSA) with half the area. By partially shorting the 90° sectoral MSA, the broadband response is obtained at a lower frequency, leading to a further area reduction. Tunable dual-band operation has been obtained by increasing the coupling between the two patches using a shorting strip for both a single-short and a fully shorted 90° sectoral MSA. © 2000 John Wiley & Sons, Inc. Microwave Opt Technol Lett 26: 143–145, 2000.

Girish Kumar

Papers

Evaluation of Municipal Solid Waste Management Scenarios using Multi-Criteria Decision Making under Fuzzy Environment

Circularly polarized space-fed microstrip antenna arrays

Efficient Algorithms for Delay Bounded Multicast Tree Generation for Multimedia Applications

Stacked microstrip antennas for broadband circular polarization

Compact gap-coupled shorted 90° sectoral microstrip antennas for broadband and dual-band operations