Hesti Susilawati
Program Studi Teknik Elektro, Fakultas Sains dan Teknik, Universitas Jenderal Soedirman, Purwokerto 53122

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Analisa Tekno-Ekonomi Perencanaan Teknologi Long Term Evolution (LTE) di Kota Tasikmalaya Susilawati, Hesti; H.P., Widhiatmoko; Faturohman, Taufik
Jurnal Rekayasa Elektrika Vol 9, No 4 (2011)
Publisher : Universitas Syiah Kuala

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Abstract

Kebutuhan komunikasi berbasis data terus meningkat. Seperti sekarang banyak gadget canggih, namun tanpa jaringan internet yang baik hanya akan berfungsi seperti ponsel biasa. Lemahnya dukungan berujung pada kelambatan dan sekali lagi vendor jaringan mencoba memberikan solusi kepada para operator. Kali ini harapan baru dengan teknologi Long Term Evolution (LTE), sebuah teknologi seluler generasi keempat (4G). Pada kesempatan ini dilakukan analisa perencanaan teknologi LTE di Kota Tasikmalaya sebagai bahan pertimbangan dalam perencanaan untuk operator yang akan membangun jaringan LTE. Hasil perhitungan menunjukan bahwa nilai spesifikasi jaringan yang direncanakan untuk luas sel dan jarak jangkauan eNode B. Untuk mencakup seluruh Kota Tasikmalaya diperlukan 21 buah eNode B, dan juga diperhitungkan analisa ekonomi berdasarkan data yang ada di lapangan berupa jumlah penduduk Kota Tasikmalaya untuk mengetahui kelayakan investasi suatu perencanaan. Dan berdasarkan perhitungan NPV diketahui bahwa perencanaan teknologi LTE adalah layak untuk dilakukan.
PENINGKATAN KAPASITAS SEL PADA SISTEM SELULER GSM Hikmaturokhman, Alfin; Susilawati, Hesti; Sari, Shinta Yunita
Journal INFOTEL Vol 1, No 2 (2009): JOURNAL INFOTEL Vol. 1 Nomor 2, November 2009
Publisher : Journal INFOTEL

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Abstract

Increasing  cell  capacity  in  GSM  applied  by  several  methods  such  as  Fixed  Channel Allocation (FCA), Channel Sharing, Channel Borrowing and Cell Splitting to solve the massive increasing  of  celluler  users  amount  in  whole  world.  It  necessary  to  calculate  the  number  of subscriber within each cell in certain busy hour based on available channel capacity in order to serve  the  traffic  capacity  in  a  cell.  In  this  work,  we  present  calculations  to  compare  cell capacity  without  increasing  cell  capacity  method  and  cell  capacity  using  increasing  capacity methods.  As  a  programming  tool   we  used  Borland  Delphi  7.  In  addition,  this  simulation software  added  with  comprehensive  explanations,  Erlang  B  Table,  and  graphics  to  make  it easier and more efficient in analyze.
SIMULASI PERUBAHAN ENERGI PER BIT DAN DERAU TERHADAP JUMLAH KANAL DAN CAKUPAN WCDMA Hikmaturokhman, Alfin; Susilawati, Hesti; Niken, Tantiningrum
Journal INFOTEL Vol 2, No 2 (2010): JOURNAL INFOTEL, VOL. 2 NOMOR 2, NOVEMBER 2010
Publisher : Journal INFOTEL

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Abstract

Eb/No parameter is the measure of signal to noise ratio for a digital communication system, it is measured at the input to the receiver and is used as the basic measure of how strong the signal is, or in other words Eb/No indicates the fluctuation of received signal strength in the receiver. Eb/No is affected by several factors, such as speed of mobile station, propagation environment and bit rate. The variations of Eb/No value will affect to the number of offered channel and coverage in WCDMA. The impact of the variation of Eb/No value could be recognized in the result of the calculations. The purpose of this research is to build simulation models by using Delphi to view and analyze the influence of Eb/No of total channels and WCDMA coverage. The results from simulation analysis showed that the larger of Eb/No and bit rate used, the number of channels on offer will be smaller and the value of BS is low sensitivity, which means loads of traffic will also offer little that would cause the quality to be better systems and transmit power MS becomes more lower in order to maintain the value of Eb/No to avoid the drop call.
RANCANG BANGUN DAN ANALISIS SECTORAL ANTENNA RADIASI SEMICIRCULAR FREKUENSI 2.4GHz UNTUK APLIKASI IEEE 802.11b/g Susilawati, Hesti
Techno Jurnal Ilmu Teknik Vol 13, No 1 (2012): Jurnal Techno April 2012
Publisher : UMP

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Abstract

Sectoral antenna is a widely used antenna for wireless communications IEEE 802.11b/g  or Wi-Fi due to its large gain and ability to determine covered area.  In this research, a sectoral antenna 2.4GHz frequency with semicircular radiation for IEEE 802.11b/g applications was designed and built.  Design and simulation is done by 4NEC2 software.  In order to get a better performance, the  design was firstly optimized. Antenna parameters studied in this research are Gain, Radiation Pattern H-plane and E-plane, Directivity, Efficiency, and VSWR. Result shown that the simulated performance of sectoral antennaafter optimizationare 13.27 dBi Gain, 120 ° H-plane beamwidth,  10 ° E-plane beamwidth, 15.36 dB Directivity, 95.95% Efficiency, and 1.37 VSWR. While real performance testing of sectoral antenna in the field are 13 dBi Gain, 125 ° H-plane beamwidth, 15 ° E-plane beamwidth, 13.42 dB Directivity, 90.68% Efficiency, and 1.6 VSWR. There are some differences in performance between simulation and application in practice.  Among the causes are the accuracy of manufacturing, quality of materials used, environmental conditions of measurement process, measurement precision, and accuracy of the instrument used. Overall, a sectoral antenna has been created properly and can be used to accomodate 2.4 GHz frequency communication, namely IEEE 802.11b/g. Keywords: antenna, sectoral, semicircular, IEEE 802.11b/g.
IMPLEMENTASI HTB (HIERARCHICAL TOKEN BUCKET) UNTUK MANAJEMEN BANDWIDTH PADA ROUTER INTERNET DI UNIVERSITAS JENDERAL SOEDIRMAN Asmoro, Dwi Ary; Susilawati, Hesti; Nugraha, Azis Wisnu Widhi
Techno Jurnal Ilmu Teknik Vol 12, No 2 (2011): Jurnal Techno Oktober 2011
Publisher : UMP

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Abstract

HTB (Hierarchical Token Bucket) bandwidth management implementation on Jenderal Soedirman University is an improvement from PCQ (Per Connection Queue) bandwidth management. PCQ divide traffic automatically based on active users, its weakness is in dividing a large amount of active users. The HTB impelentation refers to Mikrotik RouterOS queue tree, consists of class and parent that is filled by outgoing-interface. Each parent is adjusted based on IP adress block on each node, and determine packet-mark through IP-firewall-mangle. From the implementation result, 2 Global-total or main parent can be obtained, Unsoed down and Unsoed up. 29 Global-in or parent child down and 29 Global-out or parent child up which each parent max-limit is determined by 17,5 Mbps. The users satisfaction based independent sample t-test give the mean value of HTB browsing is 2,823 and PCQ browsing is 2,79. The mean value of HTB downloading is 2,616 and PCQ downloading is 2,636. Those values show that theres no significant differences in Unsoed internet users satisfaction.Keywords : Implementation of bandwidth, Mikrotik RouterOS, queue, parent. 
Simulasi Cell Breathing CDMA 2000 1x Menggunakan DELPHI Hikmaturokhman, Alfin; Susilawati, Hesti; Perdana, Ilham
Jurnal Semesta Teknika Vol 10, No 1 (2007): MEI 2007
Publisher : Jurnal Semesta Teknika

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Abstract

Cell breathing is variation of CDMA cell size depends upon the amount of traffic occurs within the cell. This work assume that the cell is in the ideal condition based on  the following assumptions,  each cell is completely isolated from the other cells, with the result that no intercell interference and signals from MS cause no interference within the cell. It makes no intracell interference occurs within the cell. In an ideal condition where is none of interference occurs, cell size and amount of users in a cell depend on several factors such as bitrate, required signal strength that MS must deliver to BS, voice activity factor, power control accuracy factor and Eb/It of the system. The result obtained by change the values of the parameters and based on the result obtained, the impact of the parameter to the cell size and amount of user in a cell could be recognized.
Static Hand Gesture Recognition of Indonesian Sign Language System Based on Backpropagation Neural Networks Asriani, Farida; Susilawati, Hesti
Makara Journal of Technology Vol 14, No 2 (2010)
Publisher : Directorate of Research and Community Services, Universitas Indonesia

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Abstract

The main objective of this research is to perform pattern recognition of static hand gesture in Indonesian sign language. Basically, pattern recognition of static hand gesture in the form of image had three phases include: 1) segmentation of the image that will be recognizable form of the hands and face, 2) feature extraction and 3) pattern classification. In this research, we used images data of 15 classes of words static. Segmentation is performed using HSV with a threshold filter based on skin color. Feature extraction performed with the Haar wavelet decomposition filter to level 2. Classification is done by applying the back propagation system of neural network architecture with 4096 neurons in input layer, 75 neurons in hidden layer and 15 neurons in output layer. The system was tested by using 225 data validation and accuracy achieved was 69%.
Peningkatan Efisiensi Penggunaan Bahan Bakar Kendaraan Bermotor Dengan Melakukan Pencarian Jarak Terdekat Menggunakan Jaringan Syaraf Tiruan Hopfield Di Wilayah Purwokerto Mubyarto, Agung; Susilawati, Hesti
Dinamika Rekayasa Vol 6, No 1 (2010): Dinamika Rekayasa - Februari 2010
Publisher : Jenderal Soedirman University

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Abstract

This proposed research concern with application of continuous Hopfield neural networks for shortest path routing in a given map, in this case Purwokerto city’s map had choosen as an example. The method that was used in this research based on the ability of continuous Hopfield neural networks for representing their neuron as choosen vertices in the given map. The result shows that the networks can produce optimal route for such source and destination node pairs. As the product of this research, we have knowledge about the shortest way from one to another location at Purwokerto, so we can increase the efficiency on fuel use by using this route
Estimasi Kinerja Kanal MIMO-OFDM Menggunakan Modulasi Adaptif Untuk Teknologi LTE Berdasar Pada Kecepatan Pelanggan Purnomo, Widhiatmoko Hery; Susilawati, Hesti; Fadli, Ari
Dinamika Rekayasa Vol 11, No 1 (2015): Dinamika Rekayasa - Februari 2015
Publisher : Jenderal Soedirman University

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Abstract

OFDM dipakai untuk teknik multiple accesspada downlink LTE. Dalam teknologi LTE, parameter kecepatan user sangat berpengaruh terhadap kualitas jaringan.Pada OFDM, estimasikanalsangatdiperlukan untuk mengatasi fading dan noise.Semakin besar kecepatan user maka semakin besar nilai fading dan noise.Untuk mengatasi masalah tersebut diperlukan estimasi kanal yang digunakan. Metode estimasi kanal yang banyak digunakan ada dua yaitu metode Least Square (LS) dan metode Minimum Mean Square Error (MMSE). Kedua metode tersebut digunakan pada penerima diam dan penerima bergerak dengan modulasi QPSK, 16-QAM, dan 64-QAM. Simulasi dilakukan untuk mengetahui metode estimasi kanal pada beberapa variasi kecepatan user. Hasil analisa menunjukkan bahwa estimasi kanal dengan metode MMSE lebih baik dibandingkan metode LS. Sedangkan pada penerima dengan kecepatan rendah memiliki kualitas jaringan yang lebih baik dibandingkan pada penerima dengan kecepatan tinggi.
Analisis Performansi VOIP (Voice Over Internet Protocol) Pada Jaringan Wimax (Worldwide Interoperability For Microwave Access) Di Wilayah DKI Jakarta Widhiatmoko, Widhiatmoko; Susilawati, Hesti; Noviandono, Rahmat K.
JURNAL INFOTEL Vol 3 No 1 (2011): Jurnal Infotel Vol.3 No.1 Mei 2011
Publisher : LPPM SEKOLAH TINGGI TEKNOLOGI TELEMATIKA TELKOM PURWOKERTO

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Abstract

VoIP adalah suatu sistem yang menggunakan jaringan internet untuk mengirimkan data paket suara dari suatu tempat ke tempat lainnya menggunakan perantara protokol IP. Dengan adanya teknologi VoIP  biaya telepon bisa lebih murah terutama untuk berkomunikasi ke luar negeri karena voice dan data menggunakan jaringan yang sama yaitu jaringan internet. VoIP merupakan layanan yang sangat rentan terhadap delay sedangkan jaringan akses yang ada saat ini memberikan delay yang cukup besar untuk VoIP. Salah satu alternatif jaringan yang dapat digunakan untuk mengatasi masalah tersebut adalah dengan memakai teknologi WiMAX  karena WiMAX dapat memberikan layanan data berkecepatan hingga 70 Mbps. Dari hasil penelitian diperoleh hasil bahwa nilai one way delay, jitter dan packet loss masih berada pada nilai yang direkomendasikan oleh ITU-T, yaitu nilai maksimum one way delay yang didapat dari pengukuran adalah 159,87 ms, untuk jitter 7,52 ms dan untuk packet loss adalah 3,175 %. One way delay dan packet loss dari hasil pengukuran digunakan untuk mencari nilai MOS yang merupakan nilai kualitas dari VoIP. Rentang nilai MOS yang didapat dari perhitungan yaitu 3,6 sampai 4,2 yang berarti VoIP layak untuk di aplikasikan ke dalam jaringan WIMAX. Sedangkan nilai maksimal throughput bisa mencapai 2,8 Mbps untuk downlink dan 0,575 Mbps untuk uplink. Dari penilitian didapat juga bahwa nilai SQI yang berada di atas nilai standar perangkat akan memberikan nilai SNR  yang cukup tinggi, sedangkan semakin tinggi nilai SQI maka nilai RSSI-nya juga semakin besar