2009 Index IEEE Antennas and Wireless Propagation Letters Vol. 8

This index covers all technical items - papers, correspondence, reviews, etc. - that appeared in this periodical during the year, and items from previous years that were commented upon or corrected in this year. Departments and other items may also be covered if they have been judged to have archival value. The Author Index contains the primary entry for each item, listed under the first author\u27s name. The primary entry includes the coauthors\u27 names, the title of the paper or other item, and its location, specified by the publication abbreviation, year, month, and inclusive pagination. The Subject Index contains entries describing the item under all appropriate subject headings, plus the first author\u27s name, the publication abbreviation, month, and year, and inclusive pages. Note that the item title is found only under the primary entry in the Author Index

Design of Circularly Polarized Modified Minkowski Fractal Based Antenna for UHF RFID Reader Applications

A compact, square shaped microstrip fractal antenna with asymmetrical pairs of T-slits for circularly polarized (CP) radiation and radio frequency identification (RFID) reader applications is proposed and experimentally investigated. Design is based on narrow slit modified Minkowski island fractal geometry. Circular polarization along with size reduction is achieved by inserting four symmetrical pairs of T-slits at the square patch boundary of the single-probe-feed radiator. Proposed geometry is tuned at resonant frequency of 914 MHz by optimization of dimensions of the two T-slits. Compactness of the antenna is achieved by increasing the overall sizes of the slits. Antenna is fabricated on FR4 substrate with a size of 47.2×47.2×1.6 mm3 (0.143λ0 X 0.143λ0 X 0.005λ0) and tested to validate the simulated results. The 3-dB axial-ratio (AR) bandwidth and impedance bandwidth of the proposed antenna design are found to be 7 MHz (911-918 MHz) and 24 MHz (909-933 MHz) respectively. A design equation is develped based on the parametric study that can be used to design a compact antenna with CP for UHF RFID applications covering the frequency range from 887 to 1023 MHz

2008 Index IEEE Transactions on Control Systems Technology Vol. 16

This index covers all technical items - papers, correspondence, reviews, etc. - that appeared in this periodical during the year, and items from previous years that were commented upon or corrected in this year. Departments and other items may also be covered if they have been judged to have archival value. The Author Index contains the primary entry for each item, listed under the first author\u27s name. The primary entry includes the coauthors\u27 names, the title of the paper or other item, and its location, specified by the publication abbreviation, year, month, and inclusive pagination. The Subject Index contains entries describing the item under all appropriate subject headings, plus the first author\u27s name, the publication abbreviation, month, and year, and inclusive pages. Note that the item title is found only under the primary entry in the Author Index

ANN Synthesis Model of Single-Feed Corner-Truncated Circularly Polarized Microstrip Antenna with an Air Gap for Wideband Applications

A computer-aided design model based on the artificial neural network (ANN) is proposed to directly obtain patch physical dimensions of the single-feed corner-truncated circularly polarized microstrip antenna (CPMA) with an air gap for wideband applications. To take account of the effect of the air gap, an equivalent relative permittivity is introduced and adopted to calculate the resonant frequency and Q-factor of square microstrip antennas for obtaining the training data sets. ANN architectures using multilayered perceptrons (MLPs) and radial basis function networks (RBFNs) are compared. Also, six learning algorithms are used to train the MLPs for comparison. It is found that MLPs trained with the Levenberg-Marquardt (LM) algorithm are better than RBFNs for the synthesis of the CPMA. An accurate model is achieved by using an MLP with three hidden layers. The model is validated by the electromagnetic simulation and measurements. It is enormously useful to antenna engineers for facilitating the design of the single-feed CPMA with an air gap

Slotted Circularly Polarized Microstrip Antenna for RFID Application

A single layer coaxial fed rectangular microstrip slotted antenna for circular polarization (CP) is proposed for radio frequency identification (RFID) application. Two triangular shaped slots and one rectangular slot along the diagonal axis of a square patch have been embedded. Due to slotted structure along the diagonal axis and less surface area, good quality of circular polarization has been obtained with the reduction in the size of microstrip antenna by 4.04 %. Circular polarization radiation performance has been studied by size and angle variation of diagonally slotted structures. The experimental result found for 10-dB return loss is 44 MHz with 10MHz of 3dB Axial Ratio (AR) bandwidth respectively at the resonant frequency 910 MHz. The overall proposed antenna size including the ground plane is 80 mm x 80 mm x 4.572 mm

Polarization reconfigurable patch antenna for compact and low cost UHF RFID reader

This paper presents a patch antenna designed for Ultra High Frequency (UHF) Radio Frequency IDentification (RFID) reader including a reconfigurable feeding for achieving polarization agility. The switchable polarization improves the polarization efficiency in comparison with standard circular polarized antenna solutions. CMOS switches are used in the reconfigurable feeding network for enabling higher power transmission and uncomplicated control with respect to solutions involving varactors and PIN diodes. Moreover, the designed patch antenna and ground planes have reduced size, for best integration of the reader in the required application. The combination of antenna and reconfigurable feeding network has been tested through simulations, showing good performance over the EU RFID frequency band (865-868 MHz). Due to its flexible and inexpensive structure, the proposed reconfigurable feeding system is a promising alternative to standard circular polarized reader antenna approaches

A Bandwidth-Enhanced, Compact, Single-Feed, Low-Profile, Multilayered, Circularly Polarized Patch Antenna

© 2002-2011 IEEE. A bandwidth-enhanced, compact, single-feed, low-profile, multilayered, circularly polarized (CP) patch antenna is presented. A corner-truncated patch is introduced as a near-field resonant parasitic element directly beneath a specially engineered radiation patch. Without sacrificing the antenna's low profile and compact size, its presence not only introduces a new pair of orthogonal near-degenerate resonant modes, but also recovers a similar pair from the cross slot of the main patch. With the aid of both circular slots and meander-line slots on these patches, the resulting three pairs of adjacent near-degenerate modes have been successfully combined with the same clockwise polarization to enhance the CP bandwidth by more than a factor of two when compared to the same-height conventional single-layer patch antennas. Measured results are in good agreement with their simulated values and demonstrate that the reported antenna is low-profile: 0.016 λ achieves a -10-dB impedance bandwidth of ∼4.6%, and a 3-dB axial-ratio bandwidth of about 2.33% along with realized gains of 4.5 ± 0.15 dBi, throughout that bandwidth. Analyses of the current distributions are used to explain the contributions of the parasitic patch, and further simulation studies validate our design guidelines and show its advantages