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All Journal Bulletin of Electrical Engineering and Informatics Semesta Teknika Journal of Electrical Technology UMY
Surahmat, Indar
Universitas Muhammadiyah Yogyakarta
Computer Science & IT Control & Systems Engineering Electrical & Electronics Engineering Energy Engineering Library & Information Science

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Analysis of Cellular Traffic Homogeneity in A Specific Area using Statistical Test Surahmat, Indar
Semesta Teknika Vol 19, No 2 (2016): NOVEMBER 2016
Publisher : Semesta Teknika

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Capacity and coverage are the most important issues on providing services by cellular operator companies. The companies measure the condition of their network and services continuously including data collection, monitoring, evaluation and future prediction.  These are part of activities to maintain grade of service. In this paper, homogeneity analysis in cellular traffic data is analysed. This step is a part of evaluation of current situation which it will be used for planning purposes. It is done by processing data provided by network statistic monitoring tool. This paper limits on analysis in a particular area. The area is served by some cell surrounding the area.  The result shows a good homogeneity amongst the cell covered a certain area during low traffic (1 am to 1 pm). Otherwise, in high traffic, the serving cells are relatively different in terms of traffic variation and homogeneity test using Fligner-Killeen is more suitable
Customization of 433 MHz Antenna for an ISM Application using Meanderline Structure Surahmat, Indar
Journal of Electrical Technology UMY Vol 1, No 3 (2017)
Publisher : Universitas Muhammadiyah Yogyakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.18196/jet.1315

Abstract

Innovation on ISM devices has been an interensting trend in robotics application. Antenna as a wireless interfacing part in communication between the device and another requires a specific design to fit an available space in the device. This paperexplores a customized design of 433MHz antenna for an application of ISM devices.Antenna is designed by using meandeline structure theory. An antenna for the frequency has been simulated and fabricated. The design is implemented in 38mm x 110mm FR-4 PCB with thickness 1.6mm. The antenna has a maximum gain 1.1 dB and SWR 1.83 at the frequency.
Analysis of Cellular Traffic Homogeneity in A Specific Area using Statistical Test Surahmat, Indar
Semesta Teknika Vol 19, No 2 (2016): NOVEMBER 2016
Publisher : Universitas Muhammadiyah Yogyakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.18196/st.v19i2.2184

Abstract

Capacity and coverage are the most important issues on providing services by cellular operator companies. The companies measure the condition of their network and services continuously including data collection, monitoring, evaluation and future prediction.  These are part of activities to maintain grade of service. In this paper, homogeneity analysis in cellular traffic data is analysed. This step is a part of evaluation of current situation which it will be used for planning purposes. It is done by processing data provided by network statistic monitoring tool. This paper limits on analysis in a particular area. The area is served by some cell surrounding the area.  The result shows a good homogeneity amongst the cell covered a certain area during low traffic (1 am to 1 pm). Otherwise, in high traffic, the serving cells are relatively different in terms of traffic variation and homogeneity test using Fligner-Killeen is more suitable
Comparative Analysis of the Use of LED and HPS Lights in PT. Bukit Asam Hasibi, Rahmat Adiprasetya Al; Jamal, Agus; Surahmat, Indar; Hardiyanto, Tio; Jusman, Yessi; Arkan, Fardhan
Journal of Electrical Technology UMY Vol 3, No 3 (2019): September
Publisher : Universitas Muhammadiyah Yogyakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.18196/jet.3358

Abstract

The lamp is the main construction facility in the company that serves as a support for the activities of the economic system and mobility in the company. An analysis of the difference between the use of LED lights with HPS lamps at PT. Bukit Asam Tbk. reference is used to recommend the use of appropriate (technical) lighting equipment for industrial areas and to obtain better cumulative costs and energy savings for the company in the future. In this study using the lamp replacement method with the same lumen level comparison. The goal is that later the level of lighting produced is the same for each lamp. From the results of this study it was found that the technical use of 70W, 150W, 250W and 400W HPS lamps has an efficacy level of 84 to 123 lm / W. Whereas the 80W, 200W, 300W, 450W LED lamps are 90 lm / W and the results of the cumulative value or the total cost of operating and maintenance costs for 15 years between HPS lamps versus the LED lights that occur is that in HPS lamps the total cost incurred amounting to 20,604,230,235 rupiahs while for LED lamps it is 27,787,386,324 rupiahs which can be seen that the use of more economical lighting is HPS lamps.
Block diagonalization precoding and power allocation for clustering small-cell networks Toha Ardi Nugraha; Indar Surahmat; Firdaus Firdaus
Bulletin of Electrical Engineering and Informatics Vol 9, No 6: December 2020
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11591/eei.v9i6.2580

Abstract

The clustering network is a solution to improve data-rate transmission in small-cells. In this case, clustering small-cells (CSCs) adopt a multiple antennas concept. The multiple antennas are used to maximize the downlink data-rate transmission at the users, but it requires precoding techniques to minimize interference among CSC users. This paper proposes a block diagonalization (BD) as a precoding technique for minimizing interference among CSC users. The performance of the BD precoding implemented on the clustering network under various numbers of small-cells. The CSC also implements a water-filling power allocation (PA-CoopWF) to distribute the available transmission power along with the CSCs antennas. To show the performance, our paper simulates two types of precoding techniques; those are the proposed BD and minimum mean square error (MMSE) in CSCs. Based on the receiver user parts under the overlapping coordination of CSCs, our method based on the BD precoding achieves considerably higher data-rate transmission compared to the MMSE precoding, especially on larger clusters. The simulation also shows that by implementing CSC with the BD in short-range distances and higher numbers of antennas, it promotes better data-rate performances compared to the MMSE precoding by 2.75 times at distance 100m and 67% at 50 antennas.
Analysis of Finite Source Traffic Model of Wireless LAN: A Case Study Indar Surahmat; Satrya Try Manggala
Journal of Electrical Technology UMY Vol 1, No 1 (2017)
Publisher : Universitas Muhammadiyah Yogyakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.18196/jet.1103

Abstract

Investigating characteristics of users and their pattern to access networks are parts of important points in traffic engineering. In this paper, those problems, specifically in wireless LAN, were observed and some related theories were explored. The observation was done in UMY, a campus located in Yogyakarta, Indonesia. In this term, we examined the traffic in an Wireless Action Point. Resuming the content of this paper, we found that the traffic had unique characteristics. For instance, during the day of measurement, the peaks of traffic were in the morning and in the afternoon. Average connected clients in all action points in UMY was between 2500 and 3000 users. When we selected an AP, the characteristic of the AP was examined, the number data size are 62.99 MB and 129.22 MB for mean and standard deviation respectively. We found that hourly trend of the usage of APs resembled self-similar model. 
Co-Authors Agus Jamal Fardhan Arkan Firdaus Firdaus Hardiyanto, Tio Hasibi, Rahmat Adiprasetya Al Jusman, Yessi Satrya Try Manggala Toha Ardi Nugraha