نتایج جستجو برای: directional pattern antenna

تعداد نتایج: 422234  

Journal: :The Journal of Korean Institute of Electromagnetic Engineering and Science 2010

Journal: :CoRR 2017
Dong-Soo Har

Wireless rechargeable sensor networks (WRSNs) consisting of sensor nodes with batteries have been at the forefront of sensing and communication technologies in the last few years. Sensor networks with different missions are being massively rolled out, particularly in the internet-ofthings commercial market. To ensure sustainable operation of WRSNs, charging in a timely fashion is very important...

Journal: :Journal of «Almaz – Antey» Air and Space Defence Corporation 2021

2010
Changyi Su Haixin Ke Todd Hubing

─ Normal mode helical antennas are widely used for RFID and mobile communications applications due to their relatively small size and omni-directional radiation pattern. However, their highly curved geometry can make the design and analysis of helical antennas that are part of larger complex structures quite difficult. A simplified model is proposed that replaces the curved helix with straight ...

2005
QIANG HU Dezhen Song Deepa Kundur Scott Miller Jim Ji Costas N. Georghiades Qiang Hu

Robotic Localization of Hostile Networked Radio Sources Using a Directional Antenna. (December 2005) Qiang Hu, B.S., Tsinghua University Co–Chairs of Advisory Committee: Dr. Dezhen Song Dr. Deepa Kundur One of the distinguishing characteristics of hostile networked radio sources (e.g., enemy sensor network nodes), is that only physical layer information and limited medium access control (MAC) l...

2004
VINAY KOLAR Nael Abu-Ghazaleh

Directional antennas have been proposed to improve the performance and capacity of Wireless MAC protocols for use in Mobile Ad hoc Networks (MANETs). Such antennas focus their beams in the direction of their receiver, allowing more of the signal power to be used in the direction of the transmission and simultaneously reducing the interference in other directions. However, several challenges and...

2014
Robart Garbacz

In this article design and optimization of square printed monopole antenna for wireless application is proposed. Theory of characteristics mode (TCM) is used for analysis of current modes on the antenna. TCM analysis shows that beveled ground plane improves the impedance bandwidth. The antenna operates over the frequency range from 1.860 GHz to 5 GHz for a VSWR ≤ 2, covering the GSM (1900-1990M...

An analytical technique is proposed for estimation of the radiation pattern of inverted-F antenna (IFA) which is mounted on the side wall of a long cylinder. The method can be applied to describe the IFA radiation in a lot of practical cases. It is indicated that this radiation pattern is a combination of radiation patterns of a horizontal and a vertical small radiator, near the cylinder with a...

2011
A. Chen T. Jiang Z. Chen D. Su

Abstract—In this paper, an ultra high frequency (UHF) low-profile antenna is proposed; it is based on the discone antenna but with addition of a back cavity, a short-circuiting structure and a two-plate top structure in order to achieve both low-profile and wideband. It is simulated and prototyped. The test results show that the antenna has an omni-directional radiation pattern in the horizonta...

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