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On behalf of the Steering Committee, it is our great pleasure to welcome you to the 2012 IEEE International Workshop on Antenna Technology (iWAT) in Tucson, Arizona on March 5–7, 2012. The workshop will continue the iWAT tradition of having a single session format augmented with interactive sessions, while providing plenty of time for interesting and rewarding professional discussions. The 2012 edition...
Today, it is well known that the performance of an electrically small antenna is a function of how well it is impedance matched to the transmitter and receiver and how well its radiation efficiency is maximized. Recently, much attention has also focused on optimizing the bandwidth or quality factor (Q) of small antennas as a function of their electrical size. In the dawn of radio's invention and development,...
The evolution of antenna technology is reviewed, from the days of Marconi to the present. Various periods over which antenna technology has been revitalized are reviewed, and the various antenna configurations developed during those periods are summarized along with some of their respective key characteristics. The history starts at the beginning of the 20th century and the respective technologies...
We introduce a novel class of flexible Radio Frequency (RF) electronics composed of conductive fibers on polymer or fabric substrates. The proposed fiber conductors and polymer substrates provide excellent RF characteristics, including mechanical flexibility and conformality. Key to the improved conductivity is the increased stitching density of the employed conductive fibers, reaching >70 stitches...
Antennas are a critical component for most if not all Army electromagnetic (EM) communications and sensor systems. The number of EM systems per platform is large and growing, which places severe restrictions on system size, weight, and power. The ever-increasing demand for bandwidth and interoperability will only make these systems more complex, driving the need for innovative basic research on multifunctional...
A true cognitive radio does not have to be limited to achieving dynamic spectrum sharing (DSS), to simply an upgraded version of Sofware Defined Radio (SDR), or even to a number-crunching machine that can perform pre-defined cross-layer optimizations. Based on this broader view, we put-forth a new vision for a futuristic cognitive radio device: We define it to be a radio device that is capable of...
Wireless sensor networks (WSNs) have potential military, industrial, biomedical, environmental, and residential applications. However, implementing sensor networks and realizing their potential faces various challenges. Sensors nodes should be small in size, ultra-low-power, and WSNs should be comprised of large quantities of sensor nodes [1][2]. These challenges emphasize the need for low-cost and...
While secret encryption keys are commonly-used for securing wireless transmissions, establishment of such keys has traditionally been accomplished using computational techniques at the higher layers of the wireless communication protocol stack. However, the multipath electromagnetic propagation typical of many environments can also be an excellent source of random variables useful for encryption key...
In this paper we present channel measurements of an ultra-wideband radio frequency identification tag (UWB RFID) with on-chip antenna (OCA). The manufactured prototype with a size of 1×1.3 mm2 transmits a carrier-based UWB signal, with adjustable pulse duration and carrier frequency. The signal bandwidth is more than 1 GHz, on a carrier frequency up to 12.5 GHz. A measurement setup has been developed...
Radio-frequency identification (RFID) systems are used in asset tracking, but general-purpose tags typically do not perform well on or near metal. Therefore, custom solutions for on metal applications are common. Many solutions for on-metal tags use spacers or electromagnetic band-gap structures resulting in designs that are extremely thick. Our approach was to incorporate materials with permeabilities...
We propose a dual-band RF device to detect the dielectric changes in polydimethylsiloxane (PDMS) microfluidic channel. Such a device, which consists of two dual-band Wilkinson power dividers (working at 2Ghz and 5GHz) and two 90° dual-band microstrip lines (providing 180° phase difference at two working frequencies), is very sensitive for identifying dielectric material changes. Moreover, by operating...
A highly selective, multiband, passive unit cell is introduced. The device is realized by incorporating a high impedance, periodic, patterned metal surface between two layers of dielectric in-between two parallel metal planes. The patterned surface is connected to the metal planes through metalized vias and through metal pins. The properties of the device have been assessed by numerically computing...
A recently proposed tunable microwave periodic structure requires many switches to dynamically change its microwave propagation and radiation characteristics. The performance of a discrete Field Effect Transistor (FET) switch package, suitable for the structure, is investigated in two potential configurations. In one configuration, the switch is co-planar with the ground plane and in the other it...
A novel hexa-band internal folded monopole/dipole/loop antenna has been proposed. The proposed antenna has four resonances in which three of them are 0.5λ, 1λ and 1.5λ modes. The distinctive feature of the antenna is an extra 2λ folded dipole mode, which has not been reported so far, is excited and utilized. All these four modes can be employed to cover the Low LTE700/GSM850/900 Band (LB: 698–960MHz)...
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