Proposed Broadband Antenna Research Articles

MODELING THE CHARACTERISTICS OF A BROADBAND ANTENNA SYSTEM FOR UAV DIRECTION FINDING

The paper presents the results of the development and modelling of a broadband antenna system for Unmanned Aerial Vehicle (UAV) direction finding. The research covered the issues of analytical description of the antenna system based on the prototype – the Vivaldi antennas. The article presents a mathematical description of the Vivaldi antenna element model. An experimental relationship between the geometrical parameters and characteristics of the antenna has been established. A review of the current state of the issue of designing antenna systems based on the concept of building ultra-wideband directional antenna elements in the absence of a phase centre has been carried out. The main trends in the modern design of broadband antenna systems are determined. The main parameters of the proposed broadband antenna are determined by the method of mathematical modelling. The parameters of the proposed antenna in the frequency range under various excitation conditions are studied, and the specifics of the application of such a system under the conditions of its possible use as part of UAV direction-finding complexes are given. The most optimal design option for an ultra-wideband antenna element is a design with an expanding slot (similar to Vivaldi antennas). At present, these antennas are widely used in various devices, namely, in radio reconnaissance devices, medical equipment, etc. Their popularity is due to the presence of advantages over other antennas, among which are a wide operating frequency range, simple design, simple manufacturing requirements, and high gain. In this paper, we considered Tapered Slot Antenna – an antenna with a widening slot. The antenna element designed and modelled in the article is a modified Vivaldi antenna (an antenna with a quasi-slot line with expansion), which is being developed for the direction-finding complex of the UAV. When calculating the TSA of the antenna element, the program for calculating the characteristics of the antennas MMANA was used in order to accelerate the study of the main laws for obtaining the required characteristics. Particular attention was paid to the possibility of changing the radiation pattern (RP) depending on the phase relations of the voltage at the input of the antenna elements.

DESIGN OF AN ULTRA-WIDEBAND UHF RFID READER ANTENNA FOR WEARABLE ANKLE TRACKING APPLICATIONS

In this paper, a broadband reader antenna is designed and manufactured for wearable ankle strap applications. The frequency range covered for S 11 < −10 dB is from 850 MHz to 1650 MHz with dipole like radiation pattern in free space. The proposed broadband antenna is manufactured with a semi-flex (Taconic RF-35) and flexible (Kapton) substrates. A good agreement between simulations and measurements has been achieved. Prototypes performances have been tested by measuring the reading distance. The maximum reading distance obtained is about 1.46 m at 865 MHz with an output power of the transmitter (P T X) of 25 dBm. Results of functional RFID test show that the proposed antenna can be used as an RFID reader antenna when it is placed on the ankle of the human body.

Characterization of Broadband Antenna Based on FR-4 Substrate Material

A simple and compact design of a coplanar waveguide (CPW)-fed broadband square patch antenna is introduced. The proposed broadband antenna is printed on a single-layer PCB with a pair of T-match like symmetric structure which acts as tuning stubs and L−shaped fed-transmission line. The antenna occupies a small radiating area 27.1×8.4 mm2 is demonstrated on an FR−4 substrate PCB with relative permittivity (εr) 4.3, and loss tangent (tan δ) 0.02 and thickness 0.76 mm. The ground plane area of the antenna is 60×60 mm2 with 50Ω CPW-fed line. The designed antenna achieved impedance bandwidth of 100.7%, (1.244 to 3.771) GHz and axial-ratio bandwidth 20.6%, (2.649 to 3.257) GHz respectively, with a return loss <-10 dB (VSWR <2), and axial ratio less than 3−dB respectively. The antenna is simulated using CST V.17 EM Simulator, and the performance of the antenna parameters like return loss, VSWR, axial ratio bandwidth (AR−BW), radiation pattern and surface current density is improvised to an acceptable limit. The analysis of results thus achieved so many similarities between the measured and simulated results

A Compact Broadband Antenna for Civil and Military Wireless Communication Applications

This paper presents a compact broadband antenna for civil and military wireless communication applications. Two prototypes of the antenna are designed and simulated. The proposed antenna is etched on low cost substrate material with compact electrical dimensions of 0.207λ×0.127λ×0.0094λmm3 at 2GHz frequency. The simple microstrip feeding technique and antenna dimensions are involved in the design to attain the proper impedance matching. An optimization of variables is carried out by multiple rigorous simulations. The designed antennas have achieved the broadband impedance bandwidth of 89.3% and 100% at 10dB return loss. The antennas exhibit omni directional radiation pattern at lower resonances and strong surface current distribution across the radiator. The peak realized gain of 5.2dBi at 10.9GHz resonant frequency is realized. Results reveal that the proposed broadband antenna is a better choice for WiMAX, UWB, land, naval and airborne radar applications.

Hybrid Plasmonic Waveguide Fed Broadband Nanoantenna for Nanophotonic Applications

In this letter, we propose a novel hybrid plasmonic waveguide fed broadband optical patch nanoantenna for nanophotonic applications. Through full wave electromagnetic simulation, we demonstrated our proposed antenna to radiate and receive signal at all optical communication windows (e.g., $\lambda =$ 850, 1310, and 1550 nm) with $\sim 86$ % bandwidth within the operational domain. Moreover, numerical results demonstrate that the proposed nanoantenna has directional radiation pattern with satisfactory gain over all three communication bands. In addition, we evaluated the antenna performances with two different array arrangements (e.g., 1-D and square array). The proposed broadband antenna can be used for prominent nanophotonic applications, such as optical wireless communication in interchip and intrachip devices, optical sensing, and optical energy harvesting.

Broadband miniaturised bow‐tie antenna for 3D microwave tomography

A broadband, miniaturised bow-tie antenna array element designed to be used in three-dimensional (3D) microwave imaging systems based on the tomographic approach is proposed. Miniaturisation is achieved by adding inductive strips to the capacitive antenna element and thereby lowering the cutoff operational frequency. Furthermore, the broadband directive radiation characteristic of the antenna with the proposed feeding network is equivalent to that of the same antenna being fed by an ideally symmetrical feeding network. This characteristic assists in the modelling of the antenna in the numerical solver. The proposed broadband antenna covering 0.85–3.25 GHz is a compact, directive element with a simple structure having the potential to be implemented in the numerical solver in 3D microwave tomography without imposing a high computational cost on the solver.

A Beam-Steering Broadband Microstrip Antenna for Noncontact Vital Sign Detection

A 2.8-4.8-GHz beam-steering broadband microstrip antenna was designed, fabricated, and measured. The proposed broadband antenna can steer a beam by switching p-i-n diodes connecting stubs to a partial ground plane. Radiation pattern measurement shows expected horizontal beam steering at the sampled frequencies of 3, 3.5, 4, and 4.5 GHz. Its beam steering is suitable for a vital-sign radar application and other applications where simple beam-steering patterns are needed.

Miniature hook-shaped monopole antenna for UWB applications

A miniature hook-shaped monopole antenna is presented for ultra-wideband (UWB) applications. This microstrip-fed antenna consists of a multi-branch radiator with overall dimensions of only 10 (L)×10 (W)×1.6 (H)mm to be easily embedded in various portable devices and with a wide impedance bandwidth covering 3–10.7 GHz. Omnidirectional radiation patterns with appreciable gain across the operating band can be obtained. Reasonably good transmission characteristic and group delay also show that the proposed broadband antenna is well suited for applications in UWB systems.

A Broadband Microstrip Antenna With Improved Gain for Noncontact Vital Sign Radar Detection

A 4.37 GHz broadband microstrip antenna with improved gain was designed and fabricated. Compared to a partial ground plane single-patch reference antenna, the proposed broadband antenna shows better directivity and improved gain performance. In addition, its radiation pattern was designed for a vital sign radar application. This antenna was implemented in a portable 4.46.7 GHz radar sensor, which can be used for noncontact vital sign detection for security or healthcare applications. The wide frequency tuning range allows the system to be tuned for an optimum transmission frequency.

Double‐ridged horn antenna for millimeter‐wave applications

AbstractThis study presents a broadband double‐ridged horn antenna for millimeter‐wave applications. The proposed broadband antenna has a bandwidth of 12.1–63.2 GHz and peak radiation gain of 12.1–19.8 dBi. The performance of this antenna is verified by the measured results and is in good agreement with the simulated results. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 2165–2167, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21884

Broadband microstrip antenna with directly coupled and parasitic patches

A new design of a rectangular microstrip antenna with a directly coupled patch and two gap-coupled parasitic patches for achieving broadband operation is proposed and experimentally studied. The proposed broadband antenna has a compact configuration such that the required realty space for implementing the antenna is minimized. Experimental results show that the proposed antenna can have an antenna bandwidth greater than six times that of a single rectangular microstrip antenna. Details of the proposed antenna are described, and experimental results of the broadband performance are presented and discussed. ©1999 John Wiley & Sons, Inc. Microwave Opt Technol Lett 22: 348–349, 1999.