JURNAL INFOTEL https://ejournal.st3telkom.ac.id/index.php/infotel <h2>About Jurnal INFOTEL</h2><table border="0"><tbody><tr><td><img src="http://ejournal.st3telkom.ac.id/public/site/images/journaladmin/cover_infotel.png" alt="telecommunication journal" width="180" height="250"></td><td align="justify" valign="top"><div style="background-color: #ebfeec; border: 1px solid #bae481; border-radius: 5px; text-align: justify; padding: 10px; font-family: sans-serif; font-size: 14px; margin-left: 10px;">Jurnal INFOTEL is a scientific journal published by Lembaga Penelitian dan Pengabdian Masyarakat (LPPM) of Institut Teknologi Telkom Purwokerto, Indonesia. Jurnal INFOTEL covers the field of <strong>informatics, telecommunication, and electronics</strong>. First published in 2009 for a printed version and published online in 2012. The aims of Jurnal INFOTEL are to disseminate research results and to improve the productivity of scientific publications. Jurnal INFOTEL is published quarterly in February, May, August and November. <strong>Starting in 2018, Jurnal INFOTEL uses English as the primary language..</strong></div></td></tr></tbody></table><h4><strong><span style="text-decoration: underline; color: #ff0000;">Call for Editors and Reviewers</span></strong></h4><div style="text-align: justify;"><p>We invite researchers, scientists, and practitioners to become editors or reviewers in Jurnal INFOTEL. If you are interested, please send us information about yourself, such as your full name, education and degree, affiliation, Scopus ID, orcid ID or other researcher ID, and the area of expertise. Please, the data is sent to email infotel@st3telkom.ac.id.<br>Thank you.</p><h4><strong>Important For Authors</strong></h4><p>Reminder for all the authors, you are expected to submit papers that:<br> 1. are original and have not been submitted to any other publication.<br> 2. have at least 15 references with 80% of scientific Journals.<br> 3. use references published on the last 5 years.<br> 4. structured using IMRaD format.<br> 5. use template specified by Jurnal INFOTEL.<br> 6. use reference manager e.g. Mendeley or others when managing the references.<br>Thank you</p><h4><strong>Registration Process in JURNAL INFOTEL</strong></h4><p>Due to security issues, the registration process in JURNAL INFOTEL is conducted by sending author's data such as full name and academic degree, email, and institutional affiliation to email <strong>infotel@st3telkom.ac.id</strong>. Author's account will be created by Admin. Account details which are username and password will be sent to Author. The Authors are welcomed to submit their paper(s) afterwards. Thank you.</p></div> LPPM INSTITUT TEKNOLOGI TELKOM PURWOKERTO en-US JURNAL INFOTEL 2085-3688 <p>Authors who publish with this journal agree to the following terms:</p> <ul> <li style="text-align: justify;">Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a <a href="http://creativecommons.org/licenses/by/3.0/" target="_new">Creative Commons Attribution License</a> that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.</li> <li style="text-align: justify;">Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.</li> <li style="text-align: justify;">Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work&nbsp;</li> </ul> A Coverage Prediction Technique for Indoor Wireless Campus Network https://ejournal.st3telkom.ac.id/index.php/infotel/article/view/434 <p>The placement of an Access Point (AP) is an important key to determine the spread of the signal. To get the optimal spread of signals, a network designer is required to understand how much coverage an AP can generate. A prediction is given to describe the coverage area produced based on AP placement for the wireless campus network, using a coordinate map modeling based on the real size for the indoor environment. The theoretical approach is used to determine the coverage area of an AP device by testing the function of the distance between the AP and the user. The results show that the signal generated by an AP will cover the entire area that is still on the LOS propagation path. The coverage area generated through AP placement in this case study reached 77.5%. The maximum distance between the AP and the user so that it is within the coverage area is 13.851m. There are still areas that are not covered by the AP, especially for the NLOS propagation path because of the obstruction around the AP.</p> Fransiska Sisilia Mukti ##submission.copyrightStatement## http://creativecommons.org/licenses/by-sa/4.0 2020-03-05 2020-03-05 11 3 73 79 10.20895/infotel.v11i3.434 Modeling and Simulation of Dual-band Yagi Antennas for Voice Communication on Microsatellite https://ejournal.st3telkom.ac.id/index.php/infotel/article/view/435 <p>The design of the dual-band Yagi antenna was developed to support voice communication through voice repeaters on microsatellites in the UHF-VHV frequency from ground stations. The Yagi antenna is a type of half lambda dipole antenna that makes it easy to obtain direction and increase gain. The antenna is designed using the method of moment through a simulation with the CST microwave studio software application. The design used as an antenna element material is a type of copper pipe cylinder. The results of the Yagi antenna design in the VHF frequency consist of one driven element, one reflector element, and three director elements, while the UHF frequency consists of one reflector element and seven directors. The results of simulation parameters are obtained, such as Bandwidth of return loss below 10 dB is 4.3 MHz<br>(VHF), and 44 MHz (UHF), VSWR (2:1) is 1.24 (VHF) and 1.36 (UHF), Gain is 9.19 dBi (VHF) and 10.5 dBi (UHF) and Beam Width is 64 degree (VHF) and 58 degree (UHF). The suitability of the antenna design target is dual-band, and Gain value in UHF is higher than VHF.</p> Muhammad Darsono ##submission.copyrightStatement## http://creativecommons.org/licenses/by-sa/4.0 2020-03-05 2020-03-05 11 3 68 72 10.20895/infotel.v11i3.435 Low-Cost Automotive Capacitive Discharge Ignition (CDI) Coil for Low Frequency Ozone Generator https://ejournal.st3telkom.ac.id/index.php/infotel/article/view/432 <p>This paper presents an alternative solution for generating ozone using a low-cost automotive Capacitive Discharge Ignition (CDI) coil. High voltage ozone generating theory is implemented using a capacitive discharge circuit that uses ignition coil as its high voltage step-up transformer. A computer simulation has been performed to confirm the validity of the circuit function. By calculation and measurement, the coil has 196,71 voltage amplification factor. Furthermore, it has been implemented at a low frequency of about 10 - 40 Hz. Meanwhile, ozone output is measured using the colorimetric method. From a series of tests, that coil implementation has successfully generated a high voltage on ozone reactor tube at 31.47 kV voltages that essential for ozone production. Change of frequency will change the ozone concentration output linearly. The test was conducted using three different frequency: 10 Hz, 20 Hz, and 40 Hz. The result has shown that the highest ozone yield was 80 mg/hour.</p> Muhammad Ikhsan Sani ##submission.copyrightStatement## http://creativecommons.org/licenses/by-sa/4.0 2020-03-08 2020-03-08 11 3 80 87 10.20895/infotel.v11i3.432 Propagation of Mobile Communication with Tree Obstacle used OFDM-QAM at 10 GHz https://ejournal.st3telkom.ac.id/index.php/infotel/article/view/439 <p>This research focused about mobile communication systems at line communication of road. Frequency communication was used 10 GHz. The tree was obstacle at every node of line communication. That communication was modeled with single diffraction. Single knife edge was used for that diffraction model. The communication transmission that used was Orthogonal Frequency Division Multiplexing. The modulation variation that used was consisted of 16 QAM and 64 QAM. Analysis that used was consisted of modulation variation, transmitter power variation, and coverage area variation. The result showed that SNR was decreased when transmitter power was increased, the value BER 64 QAM lower than BER 16 QAM, and percentage of coverage area that obtained was around 96%.</p> Andrita Ceriana Eska ##submission.copyrightStatement## http://creativecommons.org/licenses/by-sa/4.0 2020-03-10 2020-03-10 11 3 10.20895/infotel.v11i3.439 Optimation Free Space Optic (FSO) Design with Kim Model Using Space Diversity https://ejournal.st3telkom.ac.id/index.php/infotel/article/view/444 <p>The development of communication services in remote rural areas is difficult to using cable-based systems such as DSL (Digital Subscriber Line) and FTTx. One solution to solve this problem is to use a wireless system such as radio communication. FSO (Free Space Optic) communication system is a better choice compared to radio communication because the flexibility of frequency usage. One of the problems of the FSO communication system is the range not too far. The range of the FSO can be increased by space diversity method. In this study compared FSO systems that not use space diversity and FSO systems that use space diversity in three weather conditions namely clear, haze and fog. In taking data results using Kim model propagation with variations in the range between 100 – 2000 meters. The modulation used in this study is external modulation. The result of analysis of FSO performance after adding space diversity, the range of FSO increases as far as 1200 meter when clear condition. When haze conditions, FSO range increase as far as 800 meters. During fog condition, FSO range has increased as far as 300 meters. By adding space diversity, Q-factor value has increased and BER (Bit Error Rate) has decreased.</p> Triyono Subekti ##submission.copyrightStatement## http://creativecommons.org/licenses/by-sa/4.0 2020-03-10 2020-03-10 11 3 10.20895/infotel.v11i3.444