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In general, despite the seemingly many advantages of the microstrip reflectarrays, one of the most serious shortcomings of these devices is the issue of limited bandwidth [1]. To improve the bandwidth of the variable-patch-size microstrip refiectarray, the variation in the patch size must be studied more thoroughly so that its phase variation properties, and thus its bandwidth characteristics, can...
A reflectarray antenna composed of double cross loop elements of varying arm length printed on a conductor-backed substrate is introduced. Two different realizations are presented: in the first design, the lengths of both constituent arms of the cell elements are varied whereas the length of only one of the two arms is varied in the second design. Prototype reflectarrays were fabricated and measured...
In this paper, the design of circular microstrip patch antenna with sandwiching the substrates has been proposed for bandwidth enhancement. The proposed antenna is designed at 2.7GHz (S-band) using High Frequency Structural Simulator. The circular patch antenna is designed on two different substrates, FR4_epoxy and RT Duroid 5880™ and fabricated on the three layer FR4-epoxy substrate. The effect of...
The design of high antennas for wireless communication is very essential. The main drawback of the microstrip patch antenna is the low gain. The Metamaterial superstrate layer along with antenna structure improves the antenna performance parameters like gain and bandwidth. Due to Ultra refraction phenomenon, radiation is concentrated normal to the patch so that unwanted sidelobes can be avoided. This...
Pseudo-lens structures for a fully integrated, stacked open-slot on-chip antenna design for the frequency range around 180 GHz are presented. Due to the use of the silicon substrate as pseudo-lens no reflector or external dielectric lens is required. The antenna is using the multi-layered IHP 130 nm SiGe BiCMOS technology (SG13).
An omnidirectional horizontally polarized antenna with an ultra-wideband impedance and radiation bandwidth is proposed in this paper. The connected Vivaldi antenna array is firstly applied to realize a UWB horizontally polarized antenna with good omnidirectional radiation properties. The designed antenna exhibits a relative impedance bandwidth of 163.17% for |S11|<-10dB (1.45–14.3GHz). Meanwhile,...
An SIW cavity-backed dual loop antenna with broadband and circular polarization (CP) operation at Ka band is presented. The dual loop is on the top metal layer of the SIW and is coupled-fed by a longitudinal slot which is on the bottom metal layer. A microstrip-SIW transition is designed as the feed structure. Simulation results show that the antenna has a common bandwidth of 11.1% from 34 to 38 GHz...
In this paper, a high gain yagi-uda Origami antenna is introduced. Antenna is realized on a paper substrate by using origami tetrahedron structure. The radiating aperture comprises a triangular shaped monopole and two strip directors. The proposed antenna is verified by simulation and measurement results. The fabricated antenna demonstrates a peak gain of 9.6dBi at 2.6 GHz with impedance bandwidth...
Microstrip patch antennas are widely used in various wireless applications such as Wireless local area network (WLAN). WLAN is capable of providing maximum data transfer rate of 600 Mbps. The proposed antenna design has a slotted H-shaped patch and dumbbell (H) shaped Defected Ground Structure (DGS) on Flame Retardant-4 (FR-4) substrate with the microstrip feeding technique which radiates at 2.4GHz...
The virtualized network functions placement and chaining problem is formulated as a decision tree to reduce significantly the complexity of service function chaining (SFC) in clouds. Each node in the tree corresponds to a virtual resource embedding and each tree branch to the mapping of a client request in some physical candidate. This transforms the placement problem to a decision tree search. We...
Improvement in gain as well as bandwidth of microstrip antenna using reactive impedance surface and Fabry Perot cavity resonator is proposed. Suspended microstrip antenna (MSA) is designed on reactive impedance surface (RIS) backed FR4 substrate. RIS improves bandwidth, gain and efficiency of antenna due to reduced coupling between MSA and ground plane. This MSA backed RIS is placed in a FPC resonator...
Network Virtualization is one of the most promising technologies for future networking. Network Virtualization allows multiple virtual networks to coexist on same shared physical infrastructure simultaneously. One of the crucial keys in Network Virtualization is Virtual Network Embedding, which provides a method to allocate physical substrate resource to virtual network requests. In this paper, we...
In this paper, origami antennas are proposed for military field deployment. A high gain tetrahedron origami antenna (antenna #1) is introduced and then extended to circularly polarized antenna (antenna #2) for military satellite applications. Both the antennas are realized on paper substrate by using origami tetrahedron structure. The radiating aperture of antenna #1 comprises a triangular shaped...
A new approach to implementation of the virtual network embedding strategy over OpenStack cloud platform presented. We presented the OpenStack cloud platform and the problems associated with virtual network embedding. Then, conduct OpenStack dashboard customization to generate virtual network requests to process these requests. We modified OpenStack Compute module to provide bandwidth limitation for...
Network Virtualization allows multiple tenants share physical network resources flexibly. As a newly emerging architecture, Software-defined network (SDN) decouples the control plane and data plane, realizes the efficient control of network traffic. The emergence of SDN provides network virtualization a new solution for virtual network deployment. One of the most challenging issues, called Virtual...
This article presents the design of V-band hybrid coupler using new technology i.e. Substrate Integrated Waveguide (SIW) technology. This technology gives suitable components for Millimetre (mm) wave applications. In this hybrid coupler design, the level of reflection and isolation below −20dB occupy more than 2GHz of the bandwidth. The maximum peak occurs at 60GHz with a reflection coefficient of...
For a very long while the interests of small size electronic systems have been expanding. Because of progressions in integrated circuits the physical size of system is reduced. As the interest for enhanced integrated systems increments and as the system moves to higher frequencies, microwave creator searches for the up and coming era of microwave materials with enhanced adaptability. There is likewise...
This paper emphasizes on the design, analysis, fabrication and testing of honeycomb shaped ground slotted microstrip patch antenna suitable to be employed for Ku-Band Broadcasting Fixed Satellite, Mobile Satellite and Downlink Frequency applications. The proposed antenna has been designed and fabricated using flame retardant-4 (FR-4) as substrate having dielectric constant (εr) of 4.4. A flame retardant-4...
Ultra Wideband (UWB) is a new emerging and promising technology as it can accommodate higher data over a large bandwidth. we proposed a compact printed monopole UWB antenna with 3.4GHZ band-notched Characteristics. A simple square patch antenna has been fed through a 50 Ω microstrip feedline and a rectangular notch has been etched on the ground plane to reject the interference of WIMAX Band (3GHZ–4...
Network Function Virtualization (NFV) explores the virtualization technologies to offer Network-as-a- Service (NaaS) through connected virtual network functions. The network operations that were previously performed by specialized hardware are consolidated as software-based virtual network functions (VNFs). These VNFs can be implemented in the telecom clouds with high volume servers, switches and...
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