Design of a circularly polarized tag antenna for UHF RFID applications is discussed and a planar tag antenna, based on series connected loop topology is designed. Simulation based design process for axial ratio optimization is discussed and the simulation and measurement results for the proposed tag antenna are presented.

This paper addresses the performance evaluation of a modified square loop antenna design for UHF RFID applications that is excited through a narrow feed line connected to a square loop, an impedance matching network. The square loop dimensions are modified to reach a conjugate impedance matching. A gap is fixed between the feed-lines to link the chip. To achieve impedance matching, the structur...

The input impedance of a large circular loop antenna with arbitrary orientation in a cold magnetoplasma is calculated by using a transmission line theory. New impedance resonances for antennas of finite size in a magnetoplasma in the frequency region below and near the electron cyclotron frequency are indicated theoretically. The resonance peak of the impedance at the lower hybrid resonance fre...

A multiband double square loop antenna with fractal concept is proposed. The design is based on an initial model of fractal geometry and a double square slot antenna structure. The initial model of fractal geometry influences to the second frequency band and it will be carefully investigated. The radiation patterns of the proposed antenna are still similarly to bidirectional radiation pattern. ...

© 2015 ETRI Journal, Volume 37, Number 2, April 2015 http://dx.doi.org/10.4218/etrij.15.2314.0005 For this study, we designed an implantable rectangular spiral antenna for medical biotelemetry in the Medical Implant Communications Service band (402 MHz to 405 MHz). The designed antenna has a U-shaped loop for impedance matching. The antenna impedance is easily adjusted by controlling the shape ...

A novel, tri-band, planar plate-type antenna made of a compact metal plate for wireless local area network (WLAN) applications in the 2.4GHz (2400–2484MHz), 5.2GHz (5150– 5350MHz), and 5.8 GHz (5725–5825 MHz) bands is presented. The antenna was designed in a way that the operating principle includes dipole and loop resonant modes to cover the 2.4/5.2 and 5.8 GHz bands, respectively. The antenna...

This paper presents an assessment of how successful an eavesdropping attack on a contactless payment transaction can be in terms of bit and frame error rates, using an easily concealable antenna and low-cost electronics. Potential success of an eavesdropping attack largely depends on the correct recovery of the data frames used in the ISO 14443 standard. A near-field communication inductive loo...

Previous studies have shown that per-antenna rate and power control can greatly increase the data throughput of vertical Bell Labs layered space–time (V-BLAST), while an extra transmit antenna selection can provide additional diversity advantage. In this letter, we combine the transmit antenna selection with power and rate control of each antenna. We derive a simple criterion for minimum bit-er...

In this thesis micromachined antennas suitable for on-chip integration with silicon based active devices are treated. The emphasis is put on compact 24 GHz antennas, capable of being integrated in commercial SiliconGermanium (SiGe) processes using low temperature post processing micromachining techniques. Antenna types covered are the slot loop antenna, wire loop antenna, meandered dipole and t...

In this paper, a novel configuration of circular ultra-wideband (UWB) antenna with band rejection characteristic is presented. In order to obtain this characteristic, the spiral loop resonators resonating at the rejection frequency are located in both sides of the circular radiating patch. This novel structure provides the band-notched characteristic without the degradation of the UWB antenna p...