Left-Handed Metamaterial Structure for Side Lobe Suppression of Microstrip Array Antenna

In this paper, a Left-handed Metamaterial (LHM) structure is designed for side lobe suppression of a microstrip array antenna at frequency 2.8-3.1 GHz. The LHM structure is placed at the top of the microstrip array antenna with a space or gap between them. Side lobe suppression is very important for Radar system which needs antenna with high performance of its radiation properties. The linier array microstrip antenna consists of 4x1 elements. The simulation result using CST microwave studio shows that the Side Lobe Level (SLL) has been suppressed from -8.93 dB to -15.86 dB at phi = 0 while the measurement result shows suppression from -6.6 dB to -10.75 dB. Both simulation and measurement result shows a side lobe suppression using LHM structure

Bandwidth and Gain Enhancement of Microstrip Leaky-Wave Antennas with Slot and Defected Ground Structure

This paper discusses the design, simulation, and realization of a leaky-wave microstrip antenna with multiple slots and defected ground structure (DGS). The leaky-wave microstrip antenna with multiple slots and DGS was designed to operate at 5.925-6,425 GHz for wireless local area network applications (WLANs), with a gain of ≥4dBi. The antenna uses FR-4 epoxy as the substrate with a dielectric constant of 4.6 and a thickness of 1.6 mm. The leaky-wave microstrip antenna has dimensions of 45.1 mm × 24.8 mm × 1.6 mm, while the leaky-wave microstrip antenna with multiple slots and DGS has dimensions of 40.6 mm × 25 mm × 1.6 mm. The simulation results showed that adding multiple slots and DGS to the leaky-wave microstrip antenna increased the bandwidth from 280 MHz (5.859–6.139 GHz) to 691 MHz (5.854–6.545 GHz) while the gain increased from 4.47 to 5.04 dBi. Meanwhile, the measurement results showed that the bandwidth parameter increased from 273 MHz (5.877–6.150 GHz) to 684 MHz (5.845–6.529 GHz) and the gain parameter from 4.53 to 5.06 dBi at 6 GHz

Bandwidth and Gain Enhancement of Microstrip Leaky-Wave Antennas with Slot and Defected Ground Structure

This paper discusses the design, simulation, and realization of a leaky-wave microstrip antenna with multiple slots and defected ground structure (DGS). The leaky-wave microstrip antenna with multiple slots and DGS was designed to operate at 5.925-6,425 GHz for wireless local area network applications (WLANs), with a gain of ≥4dBi. The antenna uses FR-4 epoxy as the substrate with a dielectric constant of 4.6 and a thickness of 1.6 mm. The leaky-wave microstrip antenna has dimensions of 45.1 mm × 24.8 mm × 1.6 mm, while the leaky-wave microstrip antenna with multiple slots and DGS has dimensions of 40.6 mm × 25 mm × 1.6 mm. The simulation results showed that adding multiple slots and DGS to the leaky-wave microstrip antenna increased the bandwidth from 280 MHz (5.859–6.139 GHz) to 691 MHz (5.854–6.545 GHz) while the gain increased from 4.47 to 5.04 dBi. Meanwhile, the measurement results showed that the bandwidth parameter increased from 273 MHz (5.877–6.150 GHz) to 684 MHz (5.845–6.529 GHz) and the gain parameter from 4.53 to 5.06 dBi at 6 GHz

Terahertz Imaging Simulation Using Silicon-based Microstrip Antenna and Horn Antenna for Breast Cancer Detection

Breast cancer is one of the most common cancers in the world that cause a lot of mortality. Early cancer detection is crucial to decrease morbidity and mortality rates worldwide. Effective treatment or early intervention is crucial before the disease becomes more incurable. This research contributes to proposing a THz imaging system for early cancer detection, especially breast cancer, by using the benefit of THz radiation. Some approaches are made differently from the previous research, such as the imaging method, the antenna type, and the material for the antenna with the expectation of producing an efficient system and better imaging results. The system consists of one microstrip antenna as a transmitter, 25 horn antenna as a receiver and a breast tissue model. All antenna is designed to meet the requirement specification. The receiver antenna will receive power from the transmitter which will vary due to the absorption of the breast model. The received power will be visualized into a 2D color image. The simulation was able to visualize an image of the breast tissue model. Received power varies from -16.280 dB to -55.241 dB which leads to different color levels to represent the model. Antenna radiation patterns also take a role to cause the phenomenon occurred that leads to differentiation of the breast tissue type. Based on the results, this research has able to simulate a THz imaging system for breast cancer. Further modification to the system can be done to improve the imaging results

ANALISIS PERFORMANSI RADIO BASE STATION (RBS) FLEXI DI BASE STATION CON TROL (BSC) KOTA 2 JAKARTA BARAT UNTUK TRAFIK SUARA DAN DATA

Flexi Radio Base Station (RBS) Performance Analysis of Voice and Trafic on Kota 2 Jakarta Barat Base StationControl (BSC). The CDMA 2000 technology uses circuit switch method to handle voice traffic and packet switchmethod to handle data traffic between the user and RBS (Radio Base Station). These two parameters can be used tomeasure performance of the network generally, so it is necessary to optimize them. This paper analyze the performanceof RBS by measuring its parameters such as set up failure ratio, drop ratio, and occupancy. Furthermore, the trafficincrement is calculated too in order to provide information for improvement in the future. Through the analysis, it isrealized that a way to improve configuring it uniquely based on its area of scope. Some RBS need soon, but some othersdon't. Beside of that, it is also known that the voice communication effectively while data communication roughly.Keywords: CDMA, RB

Reconfiguration of Polarized Antennas for WLAN Applications

Wireless technology based on the IEEE 802.11 standard and in accordance with the KEMINFO 2019 regulations requires antennas that can adapt to changing environments. Microstrip antennas are a good solution to meet the current technological advancements because they have several advantages, such as a simple design, lightweight, easy manufacturing, and low cost. When designing a microstrip antenna, bandwidth parameters must be observed. The bandwidth of a microstrip antenna is narrow. In order to work properly, some simple techniques can be used to increase antenna bandwidth. This research proposes a reconfigurable microstrip antenna polarization using a U-slot at a frequency of (2.4– 2.485) GHz for WLAN applications. The proposed antenna reconfiguration utilizes two (2) switching mechanisms that can be turned on and off individually or simultaneously. The results of the simulation showed that Ant. 1 and Ant. 2 have a linear polarization (LP), Ant. 1 has a bandwidth of 85 MHz (2.399 – 2.484) GHz, and Ant.2 has a bandwidth of 87 MHz (2.398– 2.485) GHz, both with S-parameter values ≤-9.54 dB. Then, Ant. 3 has a right circular polarization with a bandwidth value of 124 MHz (2.397 – 2.484) GHz, and Ant. 4 has a left circular polarization with a bandwidth value of 87 MHz (2.398 – 2.485) GHz at the Axial Ratio (AR) limit of ≤ 3 dB

CIRCULARLY POLARIZED MICROSTRIP ARRAY ANTENNA FOR GROUND SEGMENT IN QUASI-ZENITH SATELLITE SYSTEM

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. Keywords: circular polarization, cross slot, microstrip antena array, Quasi-Zenith satellit

The improvement of fiber-detection method to enhance the output of amplify-received relaying on FSO communications

The performance of free-space optical (FSO) communications that using an optical amplifier (OA) in the scheme of an amplify-received (AR)-relaying has a major drawback in the detection of input signal quality under the effects of turbulence. As an OA is based on a fiber-detection (FD) method to receive and delivers a signal at the amplification process stage, there is an opportunity to implement an optical filter to improve the quality of the input signal. In this paper, as the continuation of previous work on improvement of direct-detection, the optical filter is applied on the AR-relaying of optical signal detection, implementing an OA in the receiver. The novelty proposed in this work is the improvement of FD method where the OF is designed as the integration of cone reflector, pinhole and multi-mode fiber with an OA. The optical filter produces an optical signal, the input of the OA, which minimizes the effects of turbulence, background noise and the fluctuation of the signal spectral. Thus, OA in AR-relaying produces signal output with high power and rise up below threshold level. Additionally, an OF with a lower pinhole diameter produces the best quality of the signal spectral to be delivered into an EDFA. Through this implementation, the performance of optical relaying network on FSO can be significantly improved

A Simple Folded Dipole Antenna for Medical Implant Communications at 900 MHz Band

Abstract -Nowadays, implanted medical devices that are using inductive coupling for communication, cannot be used for transmitting medical data in several meters range. This triggers us to study about implantable device systems in order for communications is enabled to be longer range by transmitting wirelessly electromagnetic signal. In this system, the external devices such as home monitoring device or portable equipment will provide the patient more mobility, and the patient or the health care provider could benefit from timely and ease of access to important patient medical information via a networked connection. Due to such advantages, small antennas for implantable devices are very important components in monitoring systems to provide wirelessly communication between a patient and an access point. This paper proposes a simple structure of a folded dipole antenna for an implantable device aimed at wireless patient monitoring applications. The implantable device is assumed to be used with a syringe injection, so the device can be simply embedded into the human body. The antenna is operated in UHF band 924 MHz, which is band of Indonesian frequency allocation for RFID applications. The antenna is small enough in this band with good performances such as S parameter, impedance bandwidth, radiation pattern and gain. The antenna has enough gain for more than 10m range communication with 250 MHz bandwidth (VSWR 1.5)