Article Per Year (5 Year)
p-Index From 2021 - 2026
1.116
P-Index
This Author published in this journals
All Journal Bulletin of Electrical Engineering and Informatics ELKOMIKA: Jurnal Teknik Energi Elektrik, Teknik Telekomunikasi, & Teknik Elektronika Jurnal Penelitian Pendidikan IPA (JPPIPA) Makara Journal of Technology International Journal of Electrical, Computer, and Biomedical Engineering (IJECBE) Journal of Robotics, Automation, and Electronics Engineering
Eko Tjipto Rahardjo
Universitas Indonesia
Agriculture, Biological Sciences & Forestry Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Civil Engineering, Building, Construction & Architecture Computer Science & IT Education Electrical & Electronics Engineering Engineering Materials Science & Nanotechnology Mechanical Engineering Medicine & Pharmacology Physics

Published : 14 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 8 Documents
Search
Journal : Makara Journal of Technology

 1 
Design of Generating Dual Frequency Operation for Triangular Microstrip Antenna Using Electromagnetic Coupling Surjati, Indra; Rahardjo, Eko Tjipto; Hartanto, Djoko
Makara Journal of Technology Vol. 9, No. 2
Publisher : UI Scholars Hub

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

Abstract

Design of Generating Dual Frequency Operation for Triangular Microstrip Antenna Using Electromagnetic Coupling. A new design is proposed in this paper by applying a pair of slits using a microstrip feed line. Therefore the microstrip line feeding system is electromagnetically coupled to the patch. The antenna works at two different frequencies in the range from 2 GHz to 4 GHz (S band frequency). The results of the simulation shows that the dual frequency operation can be created when the slit width is 1 mm and the height of the slits ranges from 10 mm to 14 mm with inter slit distance of 3 mm, 5 mm and 7 mm as well.
Two Element Microstrip Antenna Array with Defected Ground Structure Zulkifli, Fitri Yuli; Rahardjo, Eko Tjipto; Asvial, Muhamad; Hartanto, Djoko
Makara Journal of Technology Vol. 12, No. 2
Publisher : UI Scholars Hub

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

Abstract

Two Element Microstrip Antenna Array with Defected Ground Structure. This paper presents a two element microstrip antenna array using trapezium shape defected ground structure (DGS). The DGS is inserted in the ground plane between two elements of antenna array. Insertion of the DGS is intended to suppress the mutual coupling effect produced by antenna array. Simulation and measurement results were taken and compared between antenna array with and without DGS. Measurement results show that the antenna with DGS compared to antenna without DGS can suppress mutual coupling effect to 7.9 dB, improve the return loss to 33.29% from -30.188 dB to -40.24 dB and axial ratio bandwidth enhancement to 10 MHz. This bandwidth enhancement is achieved from frequency 2.63 GHz – 2.67 GHz for antenna without DGS and from frequency 2.63 GHz – 2.68 GHz for antenna with DGS. In addition, the DGS antenna also improved the antenna gain to 0.6 dB. The results show that the implementation of the trapezium DGS can improve the radiation properties of the antenna without DGS.
Circularly Polarized Microstrip Array Antenna for Ground Segment in Quasi-Zenith Satellite System Zulkifli, Fitri Yuli; Rahardjo, Eko Tjipto
Makara Journal of Technology Vol. 16, No. 1
Publisher : UI Scholars Hub

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

Abstract

In satellite communication system, antenna plays an important role. Therefore, the antenna must meet some requirements, such as high gain, circular polarization, and good directivity. In this paper, a four element linear array triangular patch microstrip antenna with cross slot is designed to be used for Quasi-Zenith satellite system. A simulation study as well as experimental study was carried out. The simulation showed that the 3 dB axial ratio bandwidth of 87 MHz (2.569-2.656 GHz) is achieved while the measured results showed 96 MHz (2.556-2.652 GHz). The linear array of 4 element antenna has a gain of 13.73 dB and maximum radiation pattern at 40° and -40°. Simulation and experiment results show that this antenna has met the characteristic requirements of Quasi-Zenith satellite.
Radiation Characteristics of a Planar Strip Dipole Antenna and a Slot Dipole Antenna for THz Applications Apriono, Catur; Rahardjo, Eko Tjipto
Makara Journal of Technology Vol. 17, No. 3
Publisher : UI Scholars Hub

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

Abstract

The development of a THz system often requires a device that is used to radiate or detect THz waves. One way to fulfill this requirement is to use an antenna. Therefore, we need to consider the radiation characteristics of an antenna working in the THz region. In this paper, we present simulation study of two dipole antennas, i.e. a planar strip dipole antenna and a slot dipole antenna. The simulation results show that a planar strip dipole antenna has a better radiation efficiency (more than 95%) compared to the slot dipole. It also shows that an efficiency of more than 98% can be achieved when using silicon dielectric substrate. Furthermore, a return loss characteristic of 38,752 dB can be achieved by using a silicon dielectric substrate and a metal layer of Au for the planar slot dipole antenna.
Performances of Free-Space Optical Communication System Over Strong Turbulence Darusalam, Ucuk; Priambodo, Purnomo Sidi; Sudibyo, Harry; Rahardjo, Eko Tjipto
Makara Journal of Technology Vol. 18, No. 1
Publisher : UI Scholars Hub

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

Abstract

We report an experimental of free-space optical communication (FSOC) system that use tube propagation simulator (TPS) as the turbulence medium. The FSOC system use wavelength of 1550 nm at the rate transmission of 1000 Mbps and amplified with EDFA at the output of +23 dBm. Index structure of 10-15–10-13 as the representation of atmosphere index turbulences are used for simulation of intensity distribution model or scintillation. The simulation use gammagamma and K model as well. The beam wave propagation models used in simulation are plane wave, spherical wave and Gaussian wave. Spherical wave achieves highest performance via gamma-gamma in strong turbulence. While Gaussian wave achieves highest performance also via K model. We also found, characteristical FSOC system performance is calculated more accurately with gamma-gamma method for strong turbulence than K model. The performances from gamma-gamma for strong turbulence are at 22.55 dB, at 5.33´10-4, and at 9.41 ´10-6.
A New Method for Simulating Power Flow Density Focused by a Silicon Lens Antenna Irradiated with Linearly Polarized THz Wave Apriono, Catur; Rahardjo, Eko Tjipto; Hiromoto, Norihisa
Makara Journal of Technology Vol. 19, No. 2
Publisher : UI Scholars Hub

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

Abstract

A terahertz system uses dielectric lens antennas for focusing and collimating beams of terahertz wave radiation. Linearly polarized terahertz wave radiation has been widely applied in the terahertz system. Therefore, an accurate method for analyzing the power flow density in the dielectric lens antenna irradiated with the linearly polarized terahertz wave radiation is important to design the terahertz systems. In optics, ray-tracing method has been used to calculate the power flow density by a number density of rays. In this study, we propose a method of ray-tracing combined with Fresnel’s transmission, including transmittance and polarization of the terahertz wave radiation to calculate power flow density in a Silicon lens antenna. We compare power flow density calculated by the proposed method with the regular ray-tracing method. When the Silicon lens antenna is irradiated with linearly polarized terahertz wave radiation, the proposed method calculates the power flow density more accurately than the regular ray-tracing.
Performance of Free-space Optical Communication Systems using Optical Amplifiers under Amplify-forward and Amplify-received Configurations Darusalam, Ucuk; Raj, Arockia Bazil; Zulkifli, Fitri Yuli; Priambodo, Purnomo Sidi; Rahardjo, Eko Tjipto
Makara Journal of Technology Vol. 24, No. 3
Publisher : UI Scholars Hub

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

Abstract

With the growth of digital technology in the stage of industrial revolution 4.0, the demand for broadcasting large amounts of information to last mile users has increased. Free-space optical (FSO) communication is one of the telecommunication platforms that has shown immense potential in meeting the demand for information broadcasting. In this work, the performance of FSO communication based on wavelength division multiplexing with a data rate of 80 Gbps is investigated through simulations. The configuration of optical amplifiers in the FSO system is set up on the basis of the amplify-forward and amplify-received configurations to expand the network. The investigation is aimed at identifying the best optical signal amplification between an erbium-doped fiber amplifier (EDFA) and a semiconductor optical amplifier (SOA) under an atmospheric channel. Simulation results show that the EDFA performs better than the SOA in terms of the optical signal amplification for eight channels of the C band. The maximum optical propagation path length under the atmospheric channel for the amplify-forward and -received schemes using the EDFA is 1.7 km, with the bit error rate achieved at 10−6.
The Relaying Network in Free-Space Optical Communications using Optical Amplifiers in Cascaded Configuration Darusalam, Ucuk; Raj, Arockia Bazil; Zulkifli, Fitri Yuli; Priambodo, Purnomo Sidi; Rahardjo, Eko Tjipto
Makara Journal of Technology Vol. 27, No. 2
Publisher : UI Scholars Hub

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

Abstract

Optical relaying is the best technique to implement free-space optical (FSO) communications as a terrestrial platform. However, atmospheric turbulence (AT) limits the optical-propagation path length. In this study, the implementation of some optical amplifiers (OAs) in cascaded configuration, namely, erbium-doped fiber amplifiers, semiconductor OAs, and Raman amplifiers (RAs), are investigated through simulation. This study aims to search for the maximum link distance of an optical propagation and enhance the FSO performance caused by each configuration of OAs. The optical relaying network consists of three nodes, with each node designed with a space of several kilometers under the influence of AT. At the end of the destination, before the receiver, an optical band-pass filter is applied to perform noise filtering. Among the OAs in the cascaded configuration, the RA can expand the link distance of the optical-propagation path length to a range of 14.7–15.9 Km under the influence of a strong AT. The signal-to-noise ratio and bit error rate of the system are in the ranges of 24.1– 19.08 dB and 7.9 × 10−15–7.4 × 10−6, respectively.
Co-Authors Basari Basari Catur Apriono Djoko Hartanto Filda Ayu Afrida Fitri Yuli Zulkifli Harry Sudibyo Indra Surjati Luh Putu Ratna Sundari Norihisa Hiromoto, Norihisa Nugroho Adi Saputro Purnomo Sidi Priambodo Rachman, Fajar Aulia Raj, Arockia Bazil Rizky Hidayat Prasetyo Soares, Fidelio Ucuk Darusalam