Design and Measurements of a Five Independent Band Patch Antenna for Different Wireless Applications

This paper presents the design of a compact microstrip patch antenna with the ability of controlling the number of bands and the operating frequencies independently. Numerical equations are derived using a curve fitting technique to obtain the centre frequency of each band. The antenna comprises a main patch and four sub-patches fed by a 50 microstrip line. It is designed to generate up to five separate modes to cover the frequency range from 900MHz to 3GHz for the operation of wireless devices supporting multiple standards including Global System for Mobile communication (GSM900, 880-960 MHz), Digital Communication System (DCS1800, 1710-1880 MHz), Universal Mobile Telecommunication System (UMTS, 1920-2170 MHz), Wireless Local Area Network (WLAN, 2400-2483.5 MHz) and low band Worldwide Interoperability for Microwave Access (WIMAX, 2.5 to 2.8 GHz).NPL SMART chamber were supported by the Measurements for Innovators (MFI) program and the National Measurement Office, an Executive Agency of the Department for Business, Innovation and Skill

A frequency reconfigurable multiband patch antenna for wireless applications

Copyright @ 2011 IEE

A reconfigurable CPW antenna for GPS, GSM and WLAN applications

Copyright @ 2011 IEEEMultiband reconfigurable antennas are receiving increasing importance in modern wireless communication systems supporting multiservice applications. The main advantage is the reduction in the size of wireless devices and allowing more space for other electronic components to be fitted. A widely tunable antenna using PIN switches was presented in [1]. Reconfigurable multiband antennas for wireless systems including satellite and terrestrial applications were reported in [2, 3]. This paper presents a new technique to electrically control the resonant frequencies by using a varactor diode. The antenna has an H-shape structure fed by a coplanar waveguide (CPW). It can generate and control up to three resonant frequencies to be used in GPS, GSM and Bluetooth/WLAN applications

Widely tunable multiband reconfigurable patch antenna for wireless applications

The official published version can be obtained from the link below - Copyright @ EuCAP 2010A design of a low profile reconfigurable microstrip patch antenna is presented. The antenna consists of four suppatches connected to one feed line, each sub-patch generates a single band. By placing a variable capacitor at the input of the sub-patches, the impedance matching frequency of the antenna can be tuned over a wide range starting from 0.92 GHz to 2.98 GHz with total tunability rang of 2060 MHz. The proposed antenna designed to operate in the Global System for Mobile communication (GSM900, 880-960 MHz)/ Digital Communication System (DCS1800, 1710-1880 MHz)/ Universal Mobile Telecommunication System (UMTS, 1920-2170 MHz)/ Wireless Local Area Network (WLAN, 2400-2483.5 MHz)/ and Worldwide Interoperability for Microwave Access (WiMAX, 2495-2700 MHz). The total size of the proposed antenna is 50 x 50 mm2 which is suitable for small wireless devices

A reconfigurable H-shape antenna for wireless applications

The official published version of this article can be obtained from the link below - Copyright @ EuCAP2010This paper presents a novel H-Shaped reconfigurable microstrip patch antenna fed by a Grounded Coplanar Waveguide (GCPW) for wireless applications. The uniqueness in the presented antenna design relies in the ability to select the number of operating frequencies electronically by using a varactor diode. The antenna structure consists of coplanar waveguide (CPW) input with an H-shape printed on a PCB and a varactor diode for reconfigurability. By electronically varying the value of the diode capacitance, the antenna can operate in a single band mode to cover Global Position System (GPS), a dual band mode to cover GPS and Global System for Mobile communications (GSM1900) or a three-band mode to cover GPS, GSM1900 and Bluetooth or Wireless Local Area Networks (WLAN)

Schwarschild metric in six dimensions - a topological study

In this article we introduce some types of the deformtion retracts of the 6D Schwarzchild making use of Lagrangian equations. The retraction of this space into itself and into geodesics has been presented. The relation between folding and deformation retract of this space has been achieved. A relation for energy conservation similar to the one obtained in four dimensions has been obtained for the six dimensional case

On the Deformation Retract of Eguchi-Hanson Space and Its Folding

We introduce the deformation retract of the Eguchi-Hanson space using Lagrangian equations. The retraction of this space into itself and into geodesics has been presented. The deformation retract of the Eguchi-Hanson space into itself and after the isometric folding has been discussed. Theorems concerning these relations have been deduced

De Novo Protein Structure Modeling from Cryoem Data Through a Dynamic Programming Algorithm in the Secondary Structure Topology Graph

Proteins are the molecules carry out the vital functions and make more than the half of dry weight in every cell. Protein in nature folds into a unique and energetically favorable 3-Dimensional (3-D) structure which is critical and unique to its biological function. In contrast to other methods for protein structure determination, Electron Cryorricroscopy (CryoEM) is able to produce volumetric maps of proteins that are poorly soluble, large and hard to crystallize. Furthermore, it studies the proteins in their native environment. Unfortunately, the volumetric maps generated by current advances in CryoEM technique produces protein maps at medium resolution about (~5 to 10Å) in which it is hard to determine the atomic-structure of the protein. However, the resolution of the volumetric maps is improving steadily, and recent works could obtain atomic models at higher resolutions (~3Å). De novo protein modeling is the process of building the structure of the protein using its CryoEM volumetric map. Thereupon, the volumetric maps at medium resolution generated by CryoEM technique proposed a new challenge. At the medium resolution, the location and orientation of secondary structure elements (SSE) can be visually and computationally identified. However, the order and direction (called protein topology) of the SSEs detected from the CryoEM volumetric map are not visible. In order to determine the protein structure, the topology of the SSEs has to be figured out and then the backbone can be built. Consequently, the topology problem has become a bottle neck for protein modeling using CryoEM In this dissertation, we focus to establish an effective computational framework to derive the atomic structure of a protein from the medium resolution CryoEM volumetric maps. This framework includes a topology graph component to rank effectively the topologies of the SSEs and a model building component. In order to generate the small subset of candidate topologies, the problem is translated into a layered graph representation. We developed a dynamic programming algorithm (TopoDP) for the new representation to overcome the problem of large search space. Our approach shows the improved accuracy, speed and memory use when compared with existing methods. However, the generating of such set was infeasible using a brute force method. Therefore, the topology graph component effectively reduces the topological space using the geometrical features of the secondary structures through a constrained K-shortest paths method in our layered graph. The model building component involves the bending of a helix and the loop construction using skeleton of the volumetric map. The forward-backward CCD is applied to bend the helices and model the loops