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

Log-periodic dipole antennas (LPDA) have been extensively used since 1960 when their properties were described by Isbell, whose work was followed by the detailed analysis of Carrel (1961). Progress in microwave integrated circuits in the last decade has created a demand for compact antennas, along with the requirement that the systems have a large bandwidth. The approach for broadband configuration used in this paper is a combination of log-periodic structure and an array of stagger tuned microstrip resonators.

Stagger tuned microstrip log-periodic antenna

This paper proposes an efficient high-gain multilayered antenna for wireless applications. The prototype antenna consists of a microstrip antenna which fed single or multiple parasitic patches fabricated on a low cost easily available FR4 superstrate. The patches on superstrate are suspended in air at an integral multiple of λo/2. The structured is designed, fabricated and tested. The measured VSWR [lt] 2 at 5.725–5.875-GHz frequency band. The proposed antennas with single parasitic patch provide 87% efficiency, SLL of −17 dB with an associated gain of 13.5 dB. The gain increases to 17.1 dB with three parasitic patches. The proposed structure can be packaged inside an application platform. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1923–1929, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23536

High‐gain multilayered antenna for wireless applications

In this paper, a broadband planar modified quasi-Yagi antenna using a two-element logperiodic dipole array as a driven element is proposed. To feed the two-element log-periodic dipole array, a simple microstrip to stripline transition as a balun is designed, which converts the unbalanced input to balanced output. The antenna is fabricated on a low cost glass epoxy FR4 substrate with dielectric constant = 4.4, substrate thickness = 1.6 mm, and loss tangent = 0.02. The overall size of the antenna is 84mm × 111 mm, which is 0.41λo × 0.54λo at the center frequency of 1.45 GHz. Measured results show a bandwidth of 41.4% for VSWR ≤ 2. A gain of 6.5 dBi ± 0.5 dB and front to back ratio (F/B) of better than 20 dB are achieved over the bandwidth. Measured results are in good agreement with the simulated ones. This antenna is useful for RFID, portable direction finding, spectrum monitoring systems, etc.

https://www.jpier.org/pierl/pierl73/04.17102005.pdf

A Broadband Planar Modified Quasi-Yagi Using Log-Periodic Antenna

In this paper, a compact waveguide monopulse comparator at Ka-band for monopulse tracking is presented. Simulated results show a bandwidth of nearly 6% for a return loss of better than 10 dB, an isolation of better than 40 dB between the ports, and a null depth better than 40 dB. There is an imbalance of +0.1/-0.8 dB and 1° in magnitude and phase respectively at the output ports.

Compact waveguide monopulse comparator at Ka-band for monopulse tracking

Two new configurations of circular wire mesh and annular ring monopole antennas have been investigated and the results are compared with the corresponding circular disc monopole antenna. For the wire mesh monopole antenna of diameter 26 cm with peripheral metal strip, the measured bandwidth for voltage standing wave ratio ≤ 2 has been obtained from 258 to 5240 MHz, which has a bandwidth ratio of 20.3:1. For annular ring monopole with outer diameter of 26 cm and inner diameter 14 cm, the measured band width for voltage standing wave ratio ≤ 2 has been obtained from 245 to 5275 MHz leading to 21.5:1 bandwidth ratio. These new configurations have less wind loading and weight as compared to circular disc monopole antenna. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 2459–2461, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21977

Girish Kumar

Papers

Stagger tuned microstrip log-periodic antenna

High‐gain multilayered antenna for wireless applications

A Broadband Planar Modified Quasi-Yagi Using Log-Periodic Antenna

Compact waveguide monopulse comparator at Ka-band for monopulse tracking

Wideband circular wire mesh and annular ring monopole antennas