Types Of Ultra-wideband Antennas Research Articles

Ultrawideband Antennas: Growth and Evolution.

Narrowband antennas fail to radiate short pulses of nano- or picosecond length over the broader band of frequencies. Therefore, Ultrawideband (UWB) technology has gained momentum over the past couple of years as it utilizes a wide range of frequencies, typically between 3.1–10.6 GHz. UWB antennas have been utilized for various applications such as ground-penetrating radars, disaster management through detection of unexploded mines, medical diagnostics, and commercial applications ranging from USB dongles to detection of cracks in highways and bridges. In the first section of the manuscript, UWB technology is detailed with its importance for future wireless communications systems. In the next section various types of UWB antennas and their design methodology are reviewed, and their important characteristics are highlighted. In section four the concept of a UWB notch antenna is presented. Here various methods to obtain the notch, such as slots, parasitic resonators, metamaterials, and filters are discussed in detail. In addition, various types of important notch antenna design with their technical specifications, advantages, and disadvantages are presented. Finally, the need of reconfigurable UWB notch antennas is discussed in the next section. Here various insight to the design of frequency reconfigurable notch antennas is discussed and presented. Overall, this article aims to showcase the beginnings of UWB technology, the reason for the emergence of notching in specific frequency bands, and ultimately the need for reconfiguring UWB antennas along with their usage.

Design of UWB snowflake slot antenna based on Koch fractal

There are many forms of wide-slot aperture printed antennas. This paper presents a new type of ultra-wideband antenna with compact structure from the fractal field. The slot structure of the antenna is composed of the third iteration of the Koch curve, and the tri-band is achieved by etching the snowflake slot on the side of the Rogers RT/duroid 5880 dielectric substrate with a relative dielectric constant of 2.2 and a thickness of 1.6 mm. On the other side, a hexagonal adjustment branch is used to enhance the coupling between the slot and the feeder to widen the bandwidth. The test results show that the antenna’s operating frequency band covers 2.2 to 13.4GHz. The H-plane radiation is omnidirectional, and the gain peak up to 10dB, which is suitable for ultra-wideband wireless communication.

An Introduction to UWB Antenna Design [Book\/Software Reviews

This textbook is a collaborative work by three authors from the National Polytechnic Institute in Mexico City, Mexico. Conceived as a reference for the development of ultrawide-band (UWB) antennas, it addresses applications in body-area networks, radar, imaging, spectrum monitoring, electronic warfare, and wireless sensor networks. The various topics considered in this textbook range from recent proposals to theory and guidelines for the design of the UWB antenna. This book begins with a very basic introduction to UWB antenna theory and a simple explanation of each type of UWB antenna. These are perfect for entry-level UWB antenna designers as well as UWB equipment designers and operators.

ULTRA-WIDEBAND DIELECTRIC-LOADED HORN ANTENNA WITH DUAL-LINEAR POLARIZATION CAPABILITY

In order to improve measurement e-ciency in electromag- netic test facilities (compact range or near-fleld range), testing probes are required to have ultra-wideband (UWB) radiation characteristics, dual-polarization capability, and interchangeable E- and H-plane far- fleld patterns. In this context, we propose a new type of UWB antenna that satisfles these requirements in the frequency range of 4 to 18GHz. For the proposed antenna, a low-loss dielectric material is loaded over pairs of balanced feeds to overcome radiation performance degrada- tion addressed in purely metallic antennas. Also, radiation patterns are further improved by employing a lens aperture and shielding struc- tures. The measured results of the flnal antenna design demonstrate broad and stable far-fleld patterns (half-power beamwidth > 45 - ), low voltage standing-wave ratio ( 23dB).

Experimental Characterization of UWB Antennas for On-Body Communications

In this paper, the radiation of three types of ultrawideband (UWB) antennas is experimentally characterized for near/on human body scenarios. The transmission performance for vertical and horizontal polarizations is measured at different body orientations. The received pulses are analyzed in the time domain by selecting Dirac impulse and sine-modulated Gaussian monocycle as source pulses. The peak-to-peak amplitudes, fidelity, and stretch ratio of the waveforms of the received pulses are computed based on the measured results. In measurements, three types of UWB antennas are studied, namely an omnidirectional monopole antenna, directional suspended plate antenna, and printed diversity antenna. From the study, it is found that the omnidirectional antenna experiences an increase in the transmission due to the reflections from the body but suffers from narrower horizontal coverage due to a higher attenuation as the body turns away from the transmit antenna compared to the directional antenna. However, the directional antenna is less sensitive to the distance of the antenna away from the body in vertical and horizontal polarizations. The diversity antenna is able to maintain high peak-to-peak amplitudes in the waveforms of received pulses for both polarizations and the high fidelity when it is placed near the body. Therefore, the printed diversity antenna is suitable for on-body-centric communications with improved quality of the overall radio-frequency link.

Novel Method of UWB Antenna Optimization for Specified Input Signal Forms by Means of Genetic Algorithm

A novel optimization procedure for the design of antennas for ultrawideband (UWB) wireless communication systems is presented. The optimization is based on the time-domain characteristics of the antenna. The optimization procedure was applied to a simplified version of the volcano smoke antenna proposed by Kraus. However, any other type of UWB antenna can be treated with the same technique. Our optimization procedure aims at finding an antenna not only with low VSWR but also a low-dispersion one which will ensure high correlation between the time-domain transmitting antenna input signal and the receiving antenna output signal. In pulse communications systems, usually an input signal form suited to a particular purpose is used. Hence, we strive to design the best antenna for a given input signal form. The optimization technique adopted here makes use of genetic algorithm (GA) search concepts. The electromagnetic analysis of the antenna is done by means of a finite-difference time-domain method using the commercially available CST Microwave Studio software