Darjat Darjat
Jurusan Teknik Elektro, Universitas Diponegoro Semarang Jl. Prof. Sudharto, SH, Kampus UNDIP Tembalang, Semarang 50275, Indonesia

Published : 62 Documents
Articles

PEMANFAATAN TEKNOLOGI RFID UNTUK SISTEM MULTI AKSES MAHASISWA P, Arief Anthadi; S, Wahyul Amien; Darjat, Darjat
TRANSMISI Vol 15, No 1 (2013): TRANSMISI
Publisher : TRANSMISI

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Abstract

Abstrak   Akses kontrol dapat dilakukan oleh personil seperti penjaga perbatasan, penjaga pintu, pemeriksa tiket, atau dengan perangkat seperti sebuah kunci (Lock). Namun ketika akses kontrol berupa seorang penjaga atau kunci manual mempunyai banyak keterbatasan, kontrol akses elektronik menggunakan sistem komputerisasi atau mirokontroler memecahkan keterbatasan tersebut. Sistem akses kontrol pintu  secara sederhana dipadukan dengan kunci (lock) saat ini telah dikembangkan seperti dipadu dengan sistem kartu (card) seperti  magnetic card, Smart Card, barcode card, dan RFID. RFID (Radio-Frequency IDentification). Dalam Penelitian ini akan dibahas mengenai pemafaatan dari teknologi RFID yang dipergunakan untuk sistem multi akses mahasiswa. RFID diaplikasikan pada kartu mahasiswa. Dengan menggunakan satu kartu,  mahasiswa  bisa mengakses tempat parkir, ruang laboratorium, dan atau melakukan absensi mahasiswa. Semua proses  divisualisasikan dengan tampilan simulasi. Kata kunci: : multi akses, RFID,tag,Reader     Abstract Access control can be done by personnel such as border guards, doormen, ticket checker, or with a device such as a lock. However, when the access control in the form of a guard or a manual lock has limitations, electronic access control using a computerized system or microcontroler solve these limitations. Access control system combined with a simple door lock (lock) has now developed such systems combined with the card (card) such as magnetic cards, Smart cards, barcode cards, and RFID, and then use a system such as fingerprint biometric (fingerprint), face (face), or the retina. RFID (Radio-Frequency Identification) is a wireless technology that favored compact to transform the commercial world. As the successor of the barcode, RFID can perform automatic control for a lot of things In this research will be discussed on pemafaatan of RFID technology used to access multiple systems students. RFID is applied to the student card. By using the card, students can access the parking, laboratory, and student attendance. All processes are visualized with a view simulations. Keywords: multi akses, RFID,tag,Reader
DESAIN PERANGKAT-KERAS KOMPONEN PENDUKUNG PENGEMBANGAN RADAR SEKUNDER UNTUK TRACKING TIGA DIMENSI TRAYEKTORI UJI COBA ROKET Darjat, Darjat
TEKNIK Volume 31, Nomor 1, Tahun 2010
Publisher : Fakultas Teknik, Universitas Diponegoro

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Abstract

Topic executed by is " Development of Secondary Radar For The Tracking Of Three Dimension Trajectory Test-Drive The National Rocket".In first year of research focussed at desain and making of component of hardware of producer of radio frequency 900 MHZ. Technological Development of rocket is not quit of other technology, one of them is secondary radar. Communications of radio data overcome through the secondary radar need a component hardware capable to awaken the radio frequency as according to wanted job frequency.This article study about method of hardware desain transceiver which usually implementation by PLL ( Phase Locked Loop) or underlayer modulation locked by the phase to arrange the VCO ( Voltage Controlled Oscillator) what is used. Component used by is IC transceiver RFM12BP integrating all function of radio frequency in single chipPrototype which is being developed by to build the transceiver FSK use the unit microcontroller , crystal, capacitor and antenna; separated. Obtained by result that system of radio frequency developed by earn the implementation for the system of secondary radar ably stable frequency at specified frequency arrangement
PEMETAAN POSISI DAN ORIENTASI KURSI RODA CERDAS BERBASIS PRINSIP DEAD RECKONING Setiawan, Iwan; Akrom, Isnan Fauzan; Darjat, Darjat
TRANSMISI Vol 11, No 2 (2009): TRANSMISI
Publisher : TRANSMISI

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Abstract

Smart wheelchairs is a kind of assistive technology implementation from mobile robot field. The main purpose of the system is enhance disable people mobility and guaranteeing safety aspect while wheelchair navigate around domestic environment. As a kind of semi autonomous smart navigation system, the smart wheelchair must be accommodate share control between automatic controller and the user (via joystic). The ultimate goal of this research is to know exactly the position and orientation of smart wheelchair using dead reckoning principle. To fulfill the goal, the smart wheelchair is equipt by quadrature rotary encoder for each wheels.From the experiments that we drawn, we have get some result: Position and orientation error will be larger for long duration of operation of wheelchairs. Fundamentally, these kinds of error result from systematic and non systematic error source. Keywords: encoder, dead reckoning, state chart, komunikasi serial, smart wheelchair
Kinerja Teknik Transmisi OFDM melalui Kanal HAPS (High Altitude Platform Station) Ferdinan, Afriandi; Santoso, Imam; Darjat, Darjat
TRANSMISI Vol 11, No 3 (2009): TRANSMISI
Publisher : TRANSMISI

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Abstract

Provision of broadband communications services in High Altitude Platform Station (HAPS) is a new idea and worthy to be discussed. One is the application of OFDM transmission technique as a medium for digital modulation in HAPS. HAPS is a new technology in the telecommunications sector at an altitude of 18-50 km (the stratosphere) and used to serve the broadband wireless access (BWA) and other multimedia devices. HAPS technology has advantages that can cover the lack of terrestrial and satellite technology. Performance of OFDM transmission technique in which a HAPS channel Rician channel can be evaluated by looking at the effect of K-factor. K-factor is the dominant signal power ratio (Line Of Sight) with multipath signal power. In real conditions on the ground, the received power is a combination of the dominant signal power and multipath signal power. The increase in elevation angle between the HAPS platform with user terminals resulted in the increasing value of K-factor and the influence that affected the performance of OFDM systems multipath fading. Effect of K-factor can be identified by computer simulation. Effect of K-factor observed by looking at the value of Bit Error Rate (BER) on the system to the value of signal to noise ratio (SNR) by varying the bitrate and frequency doppler. The results showed that the increasing value of K-factor at the same bitrate the smaller the resulting BER. This shows the better performance of OFDM systems. Meanwhile, the OFDM system performance deteriorated over increasing Doppler frequency. This is because the increasing value of K-factor at the same Doppler frequency resulting more BER value. Keywords: HAPS, OFDM, K-factor, BER, bit rate, Doppler frequency.
Sistem Pengendalian Suhu Dan Kelembaban Pada Mesin Pengering Kertas Darjat, Darjat
TRANSMISI Vol 10, No 2 (2008): TRANSMISI
Publisher : TRANSMISI

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Abstract

An effective and efficient paper drying tool for printing industry is very important. Utilize of this tool is to dry the paper will be printed to get a dry paper that have ideal temperature and humidity level. With the result that will make easier the process of production and to get the optimal quality of printed result.Focus of this Final Report is to design data acquisition humidity level and temperature system control to the paper drying machine based on fuzzy logic control using Atmega 8535 microcontroller, in order to get the paper that have ideal temperature and humidity level is about 33oC – 35.5oC and 41% of water content in 0.00075 inch of thickness for each of the sheet later  (Perry’s Chemical Engineers’ Handbook: 12.34) 10].Observation result of fuzzy logic control in paper drying system show that bigger reference of temperature offered to the system so that the time to reach steady state condition will be more longer, where the initial condition of temperature at the same value. To get the dry ideal paper result, the setting reference of temperature that appropriate is 50oC, where the drying process with 50oC reference is resulted the paper with 38.0oC temperature and 40.9% of humidity.Keyword: Paper drying system, Fuzzy logic control, ATMega 8535 microcontroller
Sistem Pengiriman Informasi Pada Sasaran Tembak Dart (Dissapear Automatically Retaliatory Target) Menggunakan Gelombang Radio Darjat, Darjat; Cristie, Meisach
TRANSMISI Vol 10, No 3 (2008): TRANSMISI
Publisher : TRANSMISI

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Abstract

Radio waves are natural resources that are limited in their use, therefore, utilization should be in accordance with the regulations set by government regulations.In the Military in the efforts to maintain the integrity of the state union indonesian republic should be ready in any situation and condition. Because the reason that every soldier must have the ability to battle, one of the firearm. Therefore required that both facilities to support the business. Currently DART (dissapear automatticaly reliatory target) or more familiar with the target shoot, shoot at the target is able to hide this himself and bring himself and the suit can give a reply if shot at the time of the specified target does not shoot.. At the end of this task will be made Dart that is able to give information to the user with more efficient with the ability to accommodate Dart still existing. At the end of the task that this information can only be obtained by viewing the objects directly target shoot is expected to be addressed, so that the user does not see objects directly target shoot, but only see a display information system only.Keywords:  Display information, DART
Pengembangan Sistem Kontrol Navigasi Kursi Roda Cerdas Menggunakan Arsitektur Subsumption Studi Kasus Door Passing Dan Corridor Following Setiawan, Iwan; Darjat, Darjat; Gusman Namara, Rano
TRANSMISI Vol 10, No 3 (2008): TRANSMISI
Publisher : TRANSMISI

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Abstract

Several research have shown that both children and adults benefit substantially from access to a means of independent mobility. While the needs of many individuals with disabilities can be satisfied with traditional manual wheelchairs, a segment of the disabled community finds it difficult or impossible to use wheelchairs independently. To accommodate this population, researchers have used technologies originally developed for mobile robots to create "smart wheelchairs." Smart wheelchairs have been the subject of research since the early 1980s. Our goal in this project is to develop a smart wheelchair with a human friendly interface for high-level controlThere are two main capability that we embedded in this wheelchairs (1) Obstacle avoidance and (2) Door passing. From the experiment result,those capability seems to be work, but there must be enchanment due to  wheelchairs comportability.Keywords  : Kursi Roda Cerdas, Arsitektur Subsumption, Joystick, Sensor UltrasonikPermalink: http://ejournal.undip.ac.id/index.php/transmisi/article/view/1603
Sistem Pengendali Sasaran Tembak DART (Disappear Automatically Retaliatory Target) Menggunakan Gelombang Radio Ajulian Zahra, Ajub; Darjat, Darjat; Darpono, Rony
TRANSMISI Vol 10, No 3 (2008): TRANSMISI
Publisher : TRANSMISI

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Abstract

As a citizen we have duty to keep our country in peace and safe, especially for military forces. Indonesian National Armed Forces keep the country safe an army needed to give a skill and proficiency for shooting. Because of that is necessary to willing a device for shooting practice, that is DART (Disappear Automatically Retaliatory Target). With this device hoped that military forces have many skills and proficiency as the way to keep the country in safety and peaceful from threat inside although outside of the country, so we can keep the united of the country. Beside this device can used by athlete as a shoot practice device that is can to increase achievement.In this final project we made control device of  DART (Disappear Automatically Retaliatory Target) that more familiar with shoot target, this shoot target can hide and appear as desire by used. This DART can give Retaliatory shoot when shooting on target is miss. The retaliatory is indicator lamp, this indicator lamp can be consider as retaliatory shoot to shooter because that target of shoot is miss. On the control device of  DART also completed with Hold using for repeat shoot.  Keyword : DART, Control system, Hold
Pewujudan Tapis Digital FIR Pemilih Frekuensi Menggunakan DSK TMS320C6713 Erwin, Gidion; Hidayatno, Achmad; Darjat, Darjat
TRANSMISI Vol 12, No 1 (2010): TRANSMISI
Publisher : TRANSMISI

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Abstract

Digital frequency selector filter is the simplest application of digital signal processing, in which process only passing signal with specific desired frequency or band frequency. Digital frequency selector filter can be implemented as software or hardware. In this final project, frequency selector filter is implemented as hardware using DSK (Digital Signal Processor Starter Kit)  TMS320C6713. In this final project, designed three type of  frequency selector filter : Low Pass Filter (LPF), High Pass Filter (HPF), and Band Pass Filter (BPF) with filter length (N) and cut-off frequency (Fc) variation. Filter coefficient is the final product of design stage. FDATool Matlab is used to help filter design and filter coefficient calculation. Then, this filter coefficient is implemented as digital filter in DSK TMS320C6713 using CCS (Code Composer Studio) v.3.1. In CCS, it is also arranged some source code to initialize internal peripheral device on DSK TMS320C6713 (Codec, McBSP, etc), initialize interrupt mode, and initialize memory mapping. Based on experiment’s result, it’s known that the implemented’s magnitude response  approriate with FDATool’s magnitude response (frequency selector filter algorithm was successfully implemented in DSK TMS320C6713). However, gain’s value at pass band region is not exactly 0 dB because resistance losses from cables and the low precision of measurement device. Based on experiment’s result, it’s also known that filter with higher filter length produces better magnitude response characteristics, especially narrower transition width characteristic. Keyword :   digital signal processing, digital filter, frequency selector filter, DSK TMS320C6713.
Perancangan dan Analisis Antena Mikrostrip dengan Metode Aperture Coupled Feed pada Frekuensi 800 MHz Pambudhi, Hanief Tegar; Darjat, Darjat; Zahra, Ajub Ajulian
TRANSMISI Vol 12, No 1 (2010): TRANSMISI
Publisher : TRANSMISI

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Abstract

Problems antenna of conductor materials is rahter complicated construction and size are ussually quite large, so for purpose such as a cellular system is considered less efficient. For this purpose requires a simple antenna, a thin, easy to manufacture, and can be connected with other circuits. Then came the idea to design a microstrip antenna that antennas.   In this final project, the Aperture Coupled Feed antennas is designed at a frequency of 800 MHz and 900 MHz. The materials used as the antennas is two layers of epoxy PCB (FR4), with 1.5 mm thick material and the dielectric constant of 4.785593. The first layer of substrate is used  as a patch of the antenna, while the second layer is used as a Coupled Aperture, and than the third layer is used as a Feed line, the Coupled Aperture is connected between the patch and Feed line. The process begins with the antennas design based on existing theories. The next step is to design and simulate the performance of the antennas using the software. The software that used for simulation and design is IE3D V12. And the last step is measurement of antennas performance based on the value the working frequency, the ratio of receive power, VSWR, and radiation patterns.  The form of radiation pattern of microstrip Aperture coupled feed antenna is directional. Result of simulation of microstrip Aperture Coupled Feed at a frequency of 800 MHz: resonant frequency = 0.801 GHz, return loss = -24.92 dB, bandwidth = 0.286 %, VSWR = 1.12, impedance matching = 51.2694 + j 1.02575, total gain = 4.02147, HPBW = 82.5923, microstrip Aperture Coupled Feed at a frequency of 900 MHz: resonant frequency = 0.900 GHz, return loss = -21.0602 dB, bandwidth = 0.344 %, VSWR = 1.192, impedance matching = 53.6359 + j -18.5635, total gain = 4.45903, HPBW = 103.2656. And on the result obtained for Aperture Coupled Feed microstrip antenna at a frequency of 800 MHz: resonant frequency = 840 MHz, VSWR = 1.32, power receieve = 0,109 mW, HPBW = 68ᵒ  and 72ᵒ, Aperture Coupled Feed microstrip antenna at a frequency of  900 MHz: resonant frequency = 920 MHz, VSWR = 1.28, power receieve = 0,042 mW, HPBW = 105ᵒ  and 135ᵒ Keyword :   substrate material, Aperture Coupled Feed, antenna parameter, the working frequency antenna
Co-Authors Achmad Chusnul Khuluqi Achmad Hidayatno Aditya Aditya Adrian Bela Widodo, Adrian Bela Afriandi Ferdinan Ahmad Siddik Prayogi, Ahmad Siddik Ajub Ajulian Zahra Ajub Ajulian Zahra Akbar Fitra Listyono, Akbar Fitra Akbar Kurnia Putra Alfa Anindita Aminuddin Rizal, Aminuddin andhika gabelly fadila pradana, andhika gabelly fadila Anton Ratrianto Arief Anthadi P Aris Triwiyatno B Devina Puspasari Bambang Hadiwijaya Budi Nugroho Budi Setiyono D Sukawati, Irawan Danang Septaditya Hidayat Syah, Danang Septaditya Danniswara, Satya Darmawan Darmawan Defriko Christian Dewandhika Eveline Eveline Firman Eka Saputra, Firman Eka Frans Scifo Gidion Erwin Hafrizal Lazuardi Susiawan Hanief Tegar Pambudhi Helmi Muhammad Shadiq Imam Santoso Imam Tri Baskoro Irawan Dharma S., Irawan Dharma Irawan Dharma Sukawati, Irawan Dharma Irvan Aditya Iskandar, Irvan Aditya Isnan Fauzan Akrom Iwan Setiawan Jayaningpang Kinantang, Jayaningpang Jefri Yandika Joanna Francisca Socaningrum Kurniahadi, Andra M. Fuad Hasan M. Pramuaji Tri Saputro, M. Pramuaji Meisach Cristie Mizanul Haq, Mizanul Muhammad Aswan Muhammad Mirza Abdalla, Muhammad Mirza Munawar Agus Riyadi Ngatelan Ngatelan Paskah Handikardo Benjamin Nainggolan R. Yudha Adi Pratama Rano Gusman Namara Rg Setiawan S Ridwan Alief Rizka Hendrawan, Rizka Rony Darpono Saiful Anwar Sandi, Harum Amalia Septiaji Tri Wibisono, Septiaji Tri Sheila Nauvaliana Shulchul Chabib Achmad Sidiq Hidayatulah, Sidiq Sudjadi Sudjadi Tedjo Sukmadi Teguh Aryanto Teguh Prakoso Wahyul Amien S Wahyul Amien Syafei Yuli Christiyono Yuli Christoyono Yuli Christyono Yusuf H. Hendrayana, Yusuf H. Zaini Agung Utama Zeta Hanif Salindri, Zeta Hanif