Bandwidth enhancement of dual-band bi-directional microstrip antenna using complementary split ring resonator with defected structure for 3/5 GHz applications

<span>This paper presents a bandwidth enhancement of a dual-band bi-directional rectangular microstrip patch antenna. The novelty of this work lies in the modification of conventional rectangular microstip patch antenna by using the combination of two techniques: a complementary split ring resonator (CSRR) and a defected patch structure (DPS). The structure of antenna was studied and investigated via computer </span><span>simulation technology (CST). The dimension and position of CSRR on the ground plane was optimized to achieve dual bandwidth and bi-directional radiation pattern characteristics. In addition, the bandwidths were enhanced by defecting suitable shape incorporated in the microstrip patch. A prototype with overall dimension of 70.45×63.73 mm² has been fabricated on FR-4 substrate. To verify the proposed design, the impedance bandwidth, gain, and radiation patterns were carried out in measurements. The measured impedance bandwidths were respectively 560 MHz (3.08-3.64 GHz) and 950 GHz (4.64-5.59 GHz) while the measured gains of each bandwidth were respectively 4.28 dBi and 4.63 dBi. The measured radiation patterns were in good agreement with simulated ones. The proposed antenna achieves wide dual bandwidth and bi-directional radiation patterns performances. Consequently, it is a promising candidate for Wi-Fi or 5G communications in specific areas such as tunnel, corridor, or transit and rail.</span>

Design and Development of Inverted U-Slot Rectangular Ring Coupled Monopole Microstrip Antenna for Quad Band Operation

This paper present a novel design and development of inverted U-slot rectangular ring coupled monopole microstrip antenna (IURCMMA) for quad band operation. The monopole microstrip antennas are commonly designed for wide band operation. However, by placing the optimum ring slots in the form of slits on the radiating patch, the antenna can be made to operate at different frequency bands. The proposed antenna operates in the frequency range of 1.5 to 10 GHz with a peak gain of 8.69 dB and gives omni directional radiation pattern in both E and H planes. The measured and simulated results of return loss are in good agreement with each other. With these features the proposed antenna may find many applications at microwave frequency range. Keywords: Monopole, Rectangular, Bandwidth, Quad band , Gain.

Monolithically integrated green-to-orange color InGaN-based nanocolumn photonic crystal LEDs with directional radiation beam profiles

In this study, the monolithic integration of LEDs with different emission colors (wavelengths of 543, 573, and 597 nm) with the directional radiation profiles was demonstrated. InGaN/GaN nanocolumn arrays ordered in a triangular lattice were prepared side by side, changing the diameter of the n-GaN nanocolumn (Dn-GaN). The periodic arrangement of the nanocolumns led to the photonic crystal (PC) effect. The photonic band edge wavelength (λB) and the InGaN bandgap were controlled by the Dn-GaN. By controlling λB closely at the bandgap wavelength, the PC effect provided directional beam radiation from the LEDs with radiation angles of approximately ±30°

Design of a New Seismoelectric Logging Instrument

To increase the accuracy of reservoir evaluation, a new type of seismoelectric logging instrument was designed. The designed tool comprises the invented sonde-structured array complex. The tool includes several modules, including a signal excitation module, data acquisition module, phased array transmitting module, impedance matching module and a main system control circuit, which are interconnected through high-speed tool bus to form a distributed architecture. UC/OS-II was used for the real-time system control. After constructing the experimental measurement system prototype of the seismoelectric logging detector, its performance was verified in the laboratory. The obtained results showed that the consistency between the multi-channel received waveform amplitude and benchmark spectrum was more than 97%. The binary phased linear array transmitting module of the instrument can realize 0° to 20° deflection and directional radiation. In the end, a field test was conducted to verify the tool’s performance in downhole conditions. The results of this test proved the effectiveness of the developed seismoelectric logging tool.

Enhancing Gain for UWB Antennas Using FSS: A Systematic Review

This review paper combs through reports that have enhanced antenna gain for ultra-wideband (UWB) frequencies using frequency-selective surface (FSS) techniques. The FSS techniques found across the research landscape were mapped onto a taxonomy in order to determine the most effective method for improving antenna gain. Additionally, this study looked into the motivation behind using FSS as a reflector in UWB frequencies to obtain directional radiation. The FSS suits multiple applications due to its exceptional ability to minimize power loss in undesired transmission areas in the antenna, as well as to hinder the interference that may occur from undesirable and wasted radiation. An efficient way to obtain constant gain over a wide range of frequencies is also elaborated in this paper. Essentially, this paper offers viable prescription to enhance antenna gain for UWB applications. Methods: A comprehensive study was performed using several imminent keywords, such as “high gain using FSS”, “gain enhancement using FSS”, “high gain UWB antennas”, and “gain enhancement of UWB antennas”, in different modifications to retrieve all related articles from three primary engines: Web of Science (WoS), IEEE Xplore, and Science Direct. Results: The 41 papers identified after a comprehensive literature review were classified into two categories. The FSS single- and multi-layer reflectors were reported in 25 and 16 papers, respectively. New direction: An effective method is proposed for FSS miniaturization and for obtaining constant gain over UWB frequencies while maintaining the return loss at −10 dB. Conclusion: The use of FSS is indeed effective and viable for gain enhancement in UWB antennas. This systematic review unravels a vast range of opportunities for researchers to bridge the identified gaps.

Design and Analysis of a Graphene Based Slotted Bowtie Optical Plasmonic Nanoantenna

A graphene-based modified bowtie plasmonic nanoantenna resonating in the optical frequency spectrum with the periodic directors created by the slots on top of the radiating structure has been proposed in this paper. In the field of nanophotonics, a few optical nanoantennas have been reported to construct multipath wireless nanolinks. At the telecommunication wavelength of 1550 nm (193.5 THz), the maximum directivity of 9.67 dBi has been reached due to the maximum absorption power of graphene sheet by selecting the chemical potential of 0.5 eV. Since graphene supports surface plasmon polariton waves and acts either as an absorptive or transparent medium for distinct chemical potentials, the proposed graphene-based slotted bowtie optical nanoantenna has been optimized to obtain a dynamically controlled triple-directional radiation beam. With this distinctive nature, a multipath intra or inter on-chip wireless nanolink for secure optical data transfer can be realized by integrating a set of our proposed optical plasmonic nanoantennas.

DESAIN ANTENA MIKROSTRIP E-SHAPED PATCH PADA FREKUENSI 5500 MHz UNTUK WIFI

Modifying the shape of the patch microstrip antenna is one way to solve the narrow bandwidth. E-Shaped patch microstrip antenna is obtained by modifying a rectangular patch mikrostrip antenna. The results on this research have succesfully compared the design and simulation antenna parameters between rectangular patch and E-shaped patch. It uses FR-4 as a substrate and works on 5500 MHz frequency for WiFi. The feeding method using a feedline method. The E-shaped patch microstrip antenna has a VSWR value of 1.04 and the antenna return loss is -33.73 dB, better than the rectangular patch. The gain of E-shaped patch is increased by almost 2.5 times and the bandwidth is increased by 10.18% compared to the rectangular patch. The radiation pattern of the two patches has the same directional radiation pattern.