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hofmann geodyna 85 service manualKaabal Abdelmoumen Abdelmalek Essaadi University Saida Ahyoud Abdelmalek Essaadi University Download full-text PDF Read full-text Download full-text PDF Read full-text Download citation Copy link Link copied Read full-text Download citation Copy link Link copied Citations (2) References (10) Figures (5) Abstract and Figures In recent years planar inverted-F antenna stay as one of the most popular antenna used in mobile phone, because of its low profile, light weight and simple structure. This study presents a simulation of a planar inverted-F antenna (PIFA) with a radiating plate to the associated ground plane by a shorting plate and a FR-4 substrate between the ground plane and the radiating plate. The PIFA antenna is fed by a coaxial cable through a SMA connector. In this work the different parameters are changed to observe their effects on the characteristics of PIFA as the resonance frequency, the length of the bandwidth and the radiation pattern.A BSTRACT: In recent years planar inverted-F antenna stay as on e of the most popu lar antenna used in mobile phone, because of its low prof ile, light weight and simple structu re. This study presents a simulat ion of a planar inverted-F an tenna (PIFA) with a radiatin g plate to the associated ground plane by a shorting plate and a FR-4 substrate between the ground plane and the radiating plate. The PIFA antenna is fed by a coaxial cable throu gh a SMA connector. In this work the different parameters are changed to observe their effects o n the characteristics of PIFA as the resonan ce frequency, the length of the bandwidth and th e radiation pattern. Today, there is a growing need to gather al l the wireless services in one device, particularly, the integration of Bluetooth technology, Wi-Fi and LTE in some portable devices with a high-speed data transmission and high quality. However, this normally requires many an tennas to cover each service, and it is not po ssible to fit them all in a small device.https://www.protravelnetwork.com/akram/know_news/admin/userfiles/ford-550-backhoe-service-manual.xml

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To address this requirement, antennas that operate in multiple bands are required to support multiple standards. So, the idea is to enh ance the fun ctionality and performance of wireless communication devices and to cover the existing wirel ess communicat ion frequency bands. The planar inverted-F antennas (PIFAs), is particularly interesting due to their compactness and suitable performance. PIFA antenn a has been adopted in portable wireless units because of its low profi le, light weight, and conformal structure (Balan is, 1982).The PIFA of the resonant freque ncy of 2.478 GHz and is satisfies the requirement to cover Wireless Local Area Network (WLAN), Bluetooth technologies and Long Term Evolution (LTE2300 and LTE2500) services. The antenna can be used in mobile phones and tablet computers. 2 A NTENNA C ONFIGURATION For the conventional PIFA antennas, each PIFA-patch element will be design ed carefully based on approximately equation (1). In pra ctice, a substrate is generally just underneath the top plate, but this will make the top plate too heavy to be supported by the shorting and feeding plates. The shorting plate with the dimensions of Wsh?h is placed under the top corn er of th e top plate. The PIFA antenna is fed by a coaxial cable through a subminiature version A (SMA) connector. The software package used for simulation is CST Microwave Studio v.11 an d High Frequency Structure Simulator (HFS S). Table 1 lists the values of di fferent variables of the PIFA propose d. 3 S IMULATED RESULTS In this study of the antenna p roposed we change one para meter to observe their effects on the characteristics of the PIFA and the other parameters are constant. There are many variables that may affect the PIFA antenna bandwidth and, therefore, numerical approaches are adopted. The effect of changing the length of top plate Lp on the resonant frequency is shown in Figure 5 (a) and on the band width is shown in Figure 5 (b).http://gjbbang.com/userData/board/ford-545a-tractor-manual.xml It is evid ent that increasing the width of the feed plate inc reases the fractional bandwidth up to a particular value then further increase in the feed plate width only serves to decrease the fractional bandwidth. 3.2 T HE CHANGES OF THE HEIGHT HA The height of top plat e h is varied from 3mm to 10mm to observe its effect while all other parameters are const ant, simulated results is shown in Figure 6(a, b). The results show in Figure 6 (a) and Figure 6 (b ) that the increase in height ha decreases the resonant frequency and the impedance bandwidth. This parameter can be decreased to enhance the impedance bandwidth and resonance frequency and is very critical as we need to have small antennas. (a) (b) Fig. 6. Cha ng es o f the hei ght ha ac cord ing re so nan ce f req uen cy and ba ndw idt h 3.3 T HE CHANGES OF THE FEED PIN POSITION The changes are mad e in the horiz ontal distance x of the PIFA from edge o f ground plane to observe their effects on the characteristics of PIFA. T he value of x i s changed from 1 t o 3.6mm while all ot her parameters are con stant. The simulated results are shown in Figure 7 (a, b). The results show th at increase in distance x increases the resonant frequency (figure 7 a) and impedance bandwidt h (figure 7 b). It is concluded tha t the placement of PIFA on groun d plane significantly affects the chara cteristics of the PIFA and feed pin needs to be placed at maximum distance x of ground plane for maximum impedan ce bandwidth. 0 0,5 1 1,5 2 2,5 3 8,5 9,2 10 11,5 13 15 frequency Ghz Lenght Lp mm 0 100 200 300 400 500 600 8,5 9,2 10 11,5 13 15 bandwidth Lenght Lp mm 1,9 2 2,1 2,2 2,3 2,4 2,5 2,6 3 4,6 7 9,4 frequency Ghz height ha mm 0 100 200 300 400 500 3 4,6 7 9,4 bandwidth height ha mm In diffe rent planes the radiation patterns for resonant frequency are close to omnidirectional. Th e approx imate omnidirection al characte ristic of this new PIFA can be seen from the d ifferent horizontal and vertical patterns.https://www.interactivelearnings.com/forum/selenium-using-c/topic/19456/dr4500-truline-manualThe results of tests and simulations showed that the highest performance and possibility of relatively easy bandwidth regulation is offered by the modified constructions of a conventional PIFA. This is due to its numerous advantages such as compact size compared to monopole antenna, high gain in both vertical and horizontal states of polarization, close to omnidirectional radiation pattern, and low manufacturing cost.. On-Line Partial Discharge Monitoring System for Power Transformers Based on the Simultaneous Detection of High Frequency, Ultra-High Frequency, and Acoustic Emission Signals Article Full-text available Jun 2020 Wojciech Sikorski Krzysztof Walczak Wieslaw Gil Cyprian Szymczak The article presents a novel on-line partial discharge (PD) monitoring system for power transformers, whose functioning is based on the simultaneous use of three unconventional methods of PD detection: high-frequency (HF), ultra-high frequency (UHF), and acoustic emission (AE). It is the first monitoring system equipped in an active dielectric window (ADW), which is a combined ultrasonic and electromagnetic PD sensor. The article discusses in detail the process of designing and building individual modules of hardware and software layers of the system, wherein the most attention was paid to the PD sensors, i.e., meandered planar inverted-F antenna (MPIFA), high-frequency current transformer (HFCT), and active dielectric window with ultrasonic transducer, which were optimized for detection of PDs occurring in oil-paper insulation. The prototype of the hybrid monitoring system was first checked on a 330 MVA large power transformer during the induced voltage test with partial discharge measurement (IVPD). Next, it was installed on a 31.5 MVA substation power transformer and integrated according to the standard IEC 61850 with SCADA (Supervisory Control and Data Acquisition) system registering voltage, active power, and oil temperature of the monitored unit. The obtained results showed high sensitivity of the manufactured PD sensors as well as the advantages of the simultaneous use of three techniques of PD detection and the possibility of discharge parameter correlation with other power transformer parameters. View Show abstract An On-Body Matched Planar Inverted-F Antenna for Biotelemetry System Conference Paper Jan 2019 Faruk Abdullah Al Khondaker Abdul Mazed Sadia Islam Md Lutfur Rahman View Low profile dual-feed Planar Inverted-F Antenna for wireless LAN applications Data Full-text available Jun 2011 Microw Opt Tech Lett Hassan Tariq Chattha Yi Huang This letter presents a new low profile dual-feed Planar. Inverted-F Antenna (PIFA) suitable for wireless LAN applications. Pattern diversity is exploited using one common radiating plate and twoThe isolation is successfully achieved mainly byThus, this single PIFA antenna can actSimulated and measured results are obtained toBy exploiting the pattern diversity, successful provision of two isolated feeding ports using one common radiating plate has been achieved. The main technique introduced is to etch the ground plane under the radiating plate to reduce the mutual coupling between the two ports. It is found that the envelope cross-correlation is less than 0.02 and the ratio of the mean effective gain between the two ports is close to unity. Thus, this new PIFA antenna can provide a better solution than two separate antennas for diversity and MIMO applications by saving space and cost. Simulated and measured results verify the conclusion. View Show abstract Small Antennas in Wireless Communications Article Jul 2012 P IEEE Hang Wong K.M. Luk Chi Hou Chan Hau-Wah Lai The objective of this paper is to provide the context, physical insight, and perspective on antennas in wireless communications. Although it does not mean to be comprehensive, the four key technologies related to small antenna designs to be reviewed and discussed, including multiband planar inverted-F antennas, broadband folded patch antennas, compact differentially fed antennas, and miniature circularly polarized patch antennas, would cover a wide range of topical interests and practical applications. A brief overview of computer software for analyzing these antennas is also provided. Hopefully, this paper will be beneficial for the diverse engineering readership of the IEEE. View Show abstract A Compact Dual-Port Diversity Antenna for Long-Term Evolution Handheld Devices Article Apr 2010 IEEE T VEH TECHNOL Qinjiang Rao Dong Wang A compact integrated dual-port diversity antenna is presented, which is suitable for long-term evolution (LTE) and wireless fidelity (Wi-Fi) applications in handheld devices. The antenna design merges two planar inverted F-shaped antennas (PIFAs) into a single-antenna structure that not only occupies less volume in a handheld device but also eliminates the need to separate two individual antenna elements, which provides further space-saving efficiency. This can be accomplished even while maintaining desirable isolation and diversity characteristics. The proposed design can thus be utilized in compact wireless handheld communication devices that require signal diversity. The simulated and experimental results, including S-parameters, radiation patterns, signal correlations, and mean effective gain values, have validated the proposed antenna design as useful for compact mobile devices. View Show abstract Planar Antennas For Wireless Communications Article Jan 2001 Kai-Kit Wong Thesis (M. Phil.)--Hong Kong University of Science and Technology, 1998. Includes bibliographical references (leaves 87-90). View Show abstract Design considerations of planar inverted-F antenna (PIFA) on a finite ground plane Conference Paper Jan 2004 J.-W. He Kah-Seng Chung The operation of a PIFA mounted on a finite ground plane is investigated. This includes the influence on the input and radiation characteristics caused by the placements of the short-circuit plate and the feed wire as well as where the antenna is mounted on a finite ground plane. It has been found that the location where the antenna is mounted on the finite ground plane has a significant impact on the resonant frequency, bandwidth and radiation characteristics. Moreover, the positions of both the short-circuit plate and the feed wire have little impact on the radiation characteristics of the PIFA. The numerical simulations have been validated by measurements. View Show abstract The Theory of Characteristic Modes Revisited: A Contribution to the Design of Antennas for Modern Applications Article Nov 2007 IEEE ANTENN PROPAG M M. Cabedo-Fabres Eva Antonino-Daviu Alejandro Valero-Nogueira Miguel Ferrando-Bataller The objective of this paper is to summarize the work that has been developed by the authors for the last several years, in order to demonstrate that the Theory of Characteristic Modes can be used to perform a systematic design of different types of antennas. Characteristic modes are real current modes that can be computed numerically for conducting bodies of arbitrary shape. Since characteristic modes form a set of orthogonal functions, they can be used to expand the total current on the surface of the body. However, this paper shows that what makes characteristic modes really attractive for antenna design is the physical insight they bring into the radiating phenomena taking place in the antenna. The resonance frequency of modes, as well as their radiating behavior, can be determined from the information provided by the eigenvalues associated with the characteristic modes. Moreover, by studying the current distribution of modes, an optimum feeding arrangement can be found in order to obtain the desired radiating behavior.The designed PIFA provides two operating bands at 2.5 GHz with a bandwidth of 300 MHz (13) and at 5.2 GHz with a bandwidth of 5700 MHz (76). The two operating bands of the antenna are controlled by adjusting the size of slot and the size of elements 1 and 2. The distribution of the specific absorption rate (SAR) of 1-g and 10-g in the head of human tissues for two positions of the antenna at 2.5 GHz and 5.2 GHz is also studied. The results of simulation and measurement of the proposed antenna are presented and discussed. View full-text Article Full-text available Multiband Planar Inverted-F Antenna with Independent Operating Bands Control for Mobile Handset Appl. The proposed PIFA has a simple geometry with four slots integrated in the radiating patch and ground plane. The PIFA occupies a small volume of 51 ? 14 ? 7.2 mm ? and is placed on the top portion of mobile phone. Each of the four operating bands can be controlled independently by the variation of a single parameter of the proposed design, with a wide control range. An omnidirectional radiation pattern to each resonant frequency is obtained with a maximum gain of 2.15 dBi at 790 MHz, 3.99 dBi at 1870 MHz, 4.57 dBi at 2550 MHz, and 6.43 dBi at 3400 MHz. The proposed PIFA is studied in the free space and in the presence of other mobile phone components such as the battery, LCD (liquid crystal display), camera, microphone, speaker, buttons, and a plastic housing. The distribution of specific absorption rate for both European and American standards for each operating band and at various distances between the antenna and the human head is also studied. View full-text Interested in research on LTE. Join ResearchGate to discover and stay up-to-date with the latest research from leading experts in LTE and many other scientific topics. Join for free ResearchGate iOS App Get it from the App Store now. Install Keep up with your stats and more Access scientific knowledge from anywhere or Discover by subject area Recruit researchers Join for free Login Email Tip: Most researchers use their institutional email address as their ResearchGate login Password Forgot password. Keep me logged in Log in or Continue with LinkedIn Continue with Google Welcome back. Keep me logged in Log in or Continue with LinkedIn Continue with Google No account. All rights reserved. Terms Privacy Copyright Imprint. One method used in A quarter-wavelength patch shorted at the far end is shown Figure 1. Consequently, the A shorting pin can also be used at the feed to a patch antenna, as shown in Figure 2. The equivalent circuit of the aboveIn particular, the. Hence, the admittance. In this manner, the resonant frequency can be altered.This introduces another design parameter to This antenna resembles The Planar Inverted-F Antenna is popular because it has a low profile and The PIFA is shown from a side view in Figure 4. In PIFAs, the shorting pin can be a plate, as shown in Figure 5: The shorting pin (or shorting post) is The PIFA is at a height h from The closer the In this case, the PIFA is resonant (has maximum Intuitively, think It needs a quarter-wavelength of space between the edge Since it is the fringing fields along the edge that give rise to radiation in You can convince yourself of this by measuring the distance The clockwise and counter-clockwise paths always What can we do? Well, it's common In this technique, we add capacitance to to the PIFA This is illustrated in Figure 6: Short circuits The distances from the feed to the shorting pin, or the feed to the open edge of the PIFA determine the In some sense, the lengths are required such that the inductance To compensate for this, we add a parallel capacitance, and (from an impedance perspective), everything remains balanced You can't just decrease the size of your PIFA, replace it with capacitance The phone's This phone also has WiMax antennas (operating at 2.6 GHz), There is a single large ground plane that supports the It is important to note that even though the FCC report labels the specific regions Feel free to Copyright 2009-2021 antenna-theory.com. PIFA, planar. A Erratum for this article has been published. Show citation Miniaturized Printed Inverted-F Antenna for Internet of Things: A Design on PCB with a Meandering Line and Shorting Strip Cheuk Yin Cheung, 1 Joseph S. M. Yuen, 2 and Steve W. Y. Mung 2 1 The Hong Kong University of Science and Technology, Hong Kong 2 Innovation Technology Company Limited, Hong Kong Show more Academic Editor: Xing Lan Received 29 Jul 2017 Revised 21 Dec 2017 Accepted 24 Jan 2018 Published 26 Mar 2018 Abstract This paper focuses on a printed inverted-F antenna (PIFA) with meandering line and meandering shorting strip under 2.4?GHz industrial, scientific, and medical (ISM) band for Internet of things (IoT) applications. Bluetooth Low Energy (BLE) technology is one of potential platforms and technologies for IoT applications under ISM band. Printed circuit board (PCB) antenna commonly used in commercial and medical applications because of its small size, low profile, and low cost compared to low temperature cofired ceramic (LTCC) technology. The proposed structure of PIFA is implemented on PCB to gain all these advantages. Replacing conventional PCB line in PIFA by the meandering line and meandering shorting strip improves the efficiency of the PIFA as well as the bandwidth. As a case study, design and measurement results of the proposed PIFA are presented. 1. Introduction Internet of things (IoT) is a concept that applies current network technology to improve different industries and environment for a higher quality of life in society. IoT is a worldwide network that provides a platform allowing big data transfer and connection between people and things. These several applications provide a successful improvement in our society. These wireless technologies are operated under 2.4?GHz industrial, scientific, and medical (ISM) band. Nowadays, minimizing the size of the wireless part especially the antenna is still the main challenging research area. They have different sizes and lengths among these LTCC antennas such as length with 7?mm, 5?mm, and 3?mm. In Figure 1(a), it shows an incident E-field propagates to a vertical dipole of length, where ? 1 is the wavelength used. If the current distribution of the dipole is uniform, the actual current distribution is nearly sinusoidal. If the same dipole is used at a longer wavelength, ? 2, so the length is only long. The current tapers almost linearly from the central feed point to zero at the ends in a triangular distribution in Figure 1(b). For triangular current distribution in Figure 1(b), the radiation resistance is smaller than those in Figure 1(a). Small values of radiation resistance indicate that the performance of the antenna is not very efficient. An antenna with a shorter length but not resonant in the correct frequency leads to poor overall performance since its resonant frequency is higher than the operating frequency, and so a matching network is added to tune to the correct resonant frequency. This matching network is used for maximum power transfer from the radio transceiver to the antenna; however, the antenna still gives poor efficiency as well as resulting extra cost and circuit area. However, the performance of the antenna depends on the quality factor Q of the capacitors used. In general, the components with higher Q have a higher cost. In this paper, a new implementation of the antenna which has the advantages of low profile, small size, and foldable configuration is presented. PIFA is like a monopole printed on the PCB, but it has a shorting feed point along the main resonant structure shown in Figure 2. It has the advantage that the folded part introduces capacitance to the input impedance of the PIFA which is cancelled by the shorting feed point. This shorting feed point configuration, therefore, reduces the antenna’s size. The matching network may be required for maximum power transfer and, hence, efficient radiation. Figure 2 Printed inverted-F antenna (PIFA). Figure 3 shows the proposed antenna which contains two parts, meandering line and meandering shorting strip. This PCB line in the conventional PIFA is replaced by the meandering line in Figure 4. The combination of horizontal and vertical lines forms turns in Figure 4, and the number of turns increases efficiency. Figure 4 Meandering line used in PIFA. Therefore, the meandering shorting strip is then added to increase its bandwidth shown in Figure 3(b). The return loss is measured by a network analyzer, and the radiation patterns are carried out by an antenna measurement system. In Figure 6, the measured return loss is shown as the red line together with the simulated result as the blue line. The return loss is better than 10?dB within the ISM band. Figure 7 shows the measured radiation patterns in total fields of the proposed PIFA at 2.45?GHz as well as the gain of the antenna in Table 2. Figure 5 Photo of proposed PIFA. Plane Peak (dBi) Average (dBi) Horizontal Vertical Horizontal Vertical Y-Z 2.31 2.75 ?4.12 ?3.35 X-Z 1.92 ?2.00 ?3.25 ?7.94 X-Y 4.00 ?1.12 ?2.51 ?7.28 Table 2 The gain of the proposed PIFA. Both need the extra components for good impedance matching. Table 3 shows the comparison table of these 3 antennas. It shows that the Walsin and Murata antennas have a little size smaller than the proposed PIFA. And there is no extra cost required (printed on the PCB) on this proposed PIFA compared to the other two antennas as well as no extra matching network and capacitive load. In Table 4, it shows that the overall gain performance is better than that of the other two antennas. Figure 8 Compared result to Walsin (left) and Murata (right) antennas. To elaborate on this, the architecture of the PIFA on PCB with meandering line and meandering shorting strip was proposed. The measurement result of return loss and gain performances has shown that it has better performances compared to the LTCC antennas and there are no extra components required for good impedance matching. This proposed PIFA is a paradigm of choice compared to others keeping the portability of devices with low cost and good performance. Conflicts of Interest The authors declare that there is no conflict of interest regarding the publication of this paper. Acknowledgments This work was supported by Innovation Technology Company Limited, Hong Kong. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Read the winning articles. Show citation Multishorting Pins PIFA Design for Multiband Communications Muhammad Sajjad Ahmad, 1 C. Y. Kim, 1 and J. G. Park 1 1 School of Electronics Engineering, Kyungpook National University, 1370 Sankyuk-Dong, Buk-Gu, Daegu 702-701, Republic of Korea Show more Academic Editor: Bing Liu Received 06 Oct 2013 Revised 16 Dec 2013 Accepted 17 Dec 2013 Published 05 Feb 2014 Abstract A novel PIFA model with multiple shorting pins is proposed for multiband, low profile wireless applications, which has the ability to work in adverse conditions. The proposed model has a planar radiating sheet, a ground plane, and sides covered with PEC boundaries. The substrate inside the antenna box is tempered in order to improve the bandwidth and gain. The enhancements applied to the proposed PIFA model show improved characteristics for this PIFA model and make it a versatile candidate for handheld, low profile, and multiband resonant communication devices. Other than these specific frequency bands, an antenna rejects any signal that is fed to it. Antennas are known for their various properties including gain, directivity, radiation pattern, specific absorption rate (SAR), and Voltage Standing Wave Ratio (VSWR). In an ordinary PIFA model, when a shorting pin is applied near the feeding point, it allows the design to be reduced in size but narrows the bandwidth at the same time. By applying different schemes and techniques to an ordinary PIFA model, we can enhance not only its bandwidth but also its gain and efficiency as well. The fact that PIFA has a flexible design and can provide multiband resonant operations makes it a favorable candidate for the antenna industry. Introducing slots in the radiating patch may allow designers to achieve resonant frequencies that are not possible for a conventional PIFA with small dimensions to resonate on. Such PIFA models, commonly known as a meandered ground plane or meandered radiating patch, have diversified PIFAs for the low profile design industry. Plenty of modified PIFA models have been designed for multiband operations; slotted PIFA, meandered ground plane PIFA, and multiple shorting pins PIFA have been successful among others. Antennas are designed and tested in almost ideal environments, but when they are exposed to conducting materials in their surroundings, they do not just shift their resonant frequency but the bandwidth and gain are changed as well. The performance of any conventional antenna is affected severely, in terms of its resonant frequency, gain, and bandwidth, in the presence of conducting bodies around the antenna. It is considered a loophole for communication devices working with such antennas. The efficiency of the antenna is reported to drop from 91 (without the hand's effect) to 41 (with the hand's effect), which might not be acceptable for communication devices which require higher efficiency. Therefore, an exquisite antenna design is needed for today's industry which can cope with such undesired situations and maintain its efficiency even in the worst conditions. Our proposed model has the ability to maintain its performance in such critical conditions. Details of our proposed antenna design are given in the following section. 2. Antenna Design Procedure The proposed antenna model is shown in Figure 1. The dielectric material is sandwiched between the radiating patch (top sheet of the antenna box ) and the ground plane of the PEC case. The dimensions of the proposed model are 65 ? 135 ? 7?mm 3. For simplicity the model is divided in two main sections: firstly, the PEC case and second the antenna box. The dimensions of the antenna box are 30 ? 15 ? 7?mm 3. The top sheet of antenna box acts as a radiating patch which contains slots around its boundary to maintain the separation between the antenna elements and the PEC case.