Installation for calibration of short dipole antennas in the automatic mode

1988 ◽  
Vol 31 (5) ◽  
pp. 498-500
Author(s):  
V. I. Tokatly ◽  
V. A. Tishchenko
2008 ◽  
Vol 5 (1) ◽  
pp. 31-38 ◽  
Author(s):  
Danker Berend

Radiated emissions from equipment commonly originate from electronic circuits that act as electric dipoles created by the signal voltage between the signal conductors or as magnetic dipoles formed by the signal current flowing in a loop. Direct emission is mostly small, but circuits often couple to long conductors or large wiring loops which act as antennas and are efficient radiators. A comparable situation exists when short dipole antennas or small wiring loops receive ambient noise (susceptibility). Usually the amplitude of noise sources or the susceptibility of circuits is an invariable. The dipole strength increases with the distance between the conductors and the area. Shielding and proper grounding decreases the interaction via unintentional antennas. Short-circuiting and the insertion of lossy ferrite cores reduce the efficiency of unintentional antennas.


Author(s):  
Larysa Bodnar ◽  
Petro Koval ◽  
Sergii Stepanov ◽  
Liudmyla Panibratets

A significant part of Ukrainian bridges on public roads is operated for more than 30 years (94 %). At the same time, the traffic volume and the weight of vehicles has increased significantly. Insufficient level of bridges maintenance funding leads to the deterioration of their technical state. The ways to ensure reliable and safe operation of bridges are considered. The procedure for determining the predicted operational status of the elements and the bridge in general, which has a scientific novelty, is proposed. In the software complex, Analytical Expert Bridges Management System (AESUM), is a function that allows tracking the changes in the operational status of bridges both in Ukraine and in each region separately. The given algorithm of the procedure for determining the predicted state of the bridge using a degradation model is described using the Nassie-Schneidermann diagram. The model of the degradation of the bridge performance which is adopted in Ukraine as a normative one, and the algorithm for its adaptation to the AESUM program complex with the function to ensure the probabilistic predicted operating condition of the bridges in the automatic mode is presented. This makes it possible, even in case of unsatisfactory performance of surveys, to have the predicted lifetime of bridges at the required time. For each bridge element it is possible to determine the residual time of operation that will allow predict the state of the elements of the structure for a certain period of time in the future. Significant interest for specialists calls for the approaches to the development of orientated perspective plans for bridge inspection and monitoring of changes in the operational status of bridges for 2009-2018 in Ukraine. For the analysis of the state of the bridge economy, the information is available on the distribution of bridges by operating state related to the administrative significance of roads, by road categories and by materials of the structures. Determining the operating state of the bridge is an important condition for making the qualified decisions as regards its maintenance. The Analytical Expert Bridges Management System (AESUM) which is implemented in Ukraine, stores the data on the monitoring the status of bridges and performs the necessary procedures to maintain them in a reliable and safe operating condition. An important result of the work is the ability to determine the distribution of bridges on the public roads of Ukraine, according to operating conditions established in the program complex of AESUM, which is presented in accordance with the data of the current year. In conditions of limited funding and in case of unsatisfactory performance of surveys, it is possible to make the reasonable management decisions regarding the repair and the reconstruction of bridges. Keywords: bridge management system, operating condition, predicted operating condition, model of degradation, bridge survey plan, highway bridge.


2017 ◽  
Vol 3 (3) ◽  
pp. 140
Author(s):  
Suci Rahmatia ◽  
Putri Wulandari ◽  
Nurul Khadiko ◽  
Fitria Gani Sulistya

<p><em>Abstrak </em><strong> - Antena merupakan alat pemancar yang akrab dengan aktifitas sehari-hari dan mudah sekali dijumpai, di rumah, di gedung, bahkan pada alat komunikasi yang digunakan. Salah satu antena yang sering digunakan adalah antena televisi. Antena televisi yang sering digunakan adalah Yagi-Uda yang biasanya dipakai sebagai outdoor antena dan antena dipole yang biasanya digunakan untuk indoor antena. Masing – masing jenis antena memiliki kriteria dan keuntungan berdasarkan dari kebutuhan penggunaannya. Baik antena dipole maupun antena Yagi-Uda memiliki perbedaan diantaranya adalah besar bandwidth, nilai gain, dan pola radiasi. Pada paper ini dapat diketahui bahwa bandwidth yang dimiliki antena yagi-uda lebih besar daripada antena dipole yakni 0.39943 MHz untuk antena yagi-uda dan 0.16569 MHz untuk antena dipole. Begitupula dengan besar Gain yang dimiliki antena Yagi-Uda (6.64 dBi) lebih besar dibandingkan dengan gain dari antena dipole (2.29 dBi). Perbedaan ini dikarenakan faktor elemen director dan ketebalannya.</strong></p><p><strong><br /></strong></p><p><strong><em>Kata Kunci</em></strong> – <em>Atena Televisi, Atena Yagi-Uda, Atena Dipole, Gain, Bandwidth</em></p><p><em> </em></p><p><em>Abstract</em> <strong>- Antenna is a transmitter tool that is familiar with daily activity and easy to find at home, in the building, even on the communication tool used. One of antenna that is often used is a television antenna. Television antennas are often used is Yagi-Uda which is usually used as an outdoor antenna and dipole antenna that is usually used for indoor antennas. Each type of antenna has the criteria and advantages based on the needs of its use. Both dipole antennas and Yagi-Uda antennas have differences among them are bandwidth, gain, and radiation pattern. In this paper it can be seen that the bandwidth of yagi-uda antenna is bigger than dipole antenna that is 0.39943 MHz for Yagi-Uda antenna and 0.16569 MHz for dipole antenna. Neither the large Gain of the Yagi-Uda antenna (6.64 dBi) is greater than the gain of the dipole antenna (2.29 dBi). This difference is due to element factor of director and its thickness.</strong></p><p><strong><br /></strong></p><p><strong><em>Keywords</em></strong><strong> – </strong><em>Television Antenna, Yagi-Uda Antenna, Dipole Antenna, Gain, Bandwidth</em><strong> </strong></p>


2021 ◽  
pp. 004051752110134
Author(s):  
Daniel Agu ◽  
Rachel J Eike ◽  
Allyson Cliett ◽  
Dawn Michaelson ◽  
Rinn Cloud ◽  
...  

E-textile antennas have the potential to be the premier on-body wearable sensor. Embroidery techniques, which can be applied to produce e-textile antennas, assist in large production volumes and fast production speeds. This paper focuses on the effects of three commonly used embroidery parameters, namely stitch type, conductive thread location, and stabilizer, on the performance of embroidered dipole antennas in order to determine the ideal embroidery combination for optimal antenna performance. Fifty-four dipole antenna samples were fabricated and measured at the industrial, scientific, and medical (ISM) frequency band of 2.45 GHz. The results of this study show that machine-embroidered antenna designs with satin stitches resonate at a lower frequency and exhibit a lower transmission gain compared with those made with contour stiches, and the conductive thread location in the bobbin location plus the use of a water-soluble stabilizer can help improve impedance matching.


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