Dual elliptically tapered antipodal slot antenna loaded by curved terminations for ultrawideband applications

Abstract

[1] The dual elliptically tapered antipodal slot antenna (DETASA) is a modified version of the antipodal Vivaldi antenna. The DETASA is formed by elliptical tapering of the inner and outer edges of the slotline conductors of the antipodal Vivaldi radiator. To enhance the performance of the DETASA, this paper presents a modified configuration by using curved conducting terminations at the end of the slotline conductors. The proposed DETASA has the advantages of extended lower operating frequency, flatter gain response, symmetrical radiation patterns, and improved impedance matching across the operating band over the conventional DETASA. As an example, a prototype covering the ultrawideband (UWB) frequency range (3.1-10.6 GHz) is designed and characterized in terms of impedance matching, gain, radiation pattern, transfer function, and group delay in the frequency domain, as well as impulse response and fidelity in the time domain. The prototype which is made on a 0.8128 mm Rogers RO4003 substrate with the dimensions of 80 Â 80 mm shows good impedance and radiation performance over 3-20 GHz: Return loss is less than -10 dB; gain variation is less than 4 dB (4-8 dBi); and symmetrical radiation patterns and constant group delay have also been achieved. In the time domain, the prototype features good impulse response and high fidelity (F is more than 0.9) as well. The simulated and measured results show that the proposed DETASA is capable of providing enhanced impedance and radiation performance suitable, in particular, for UWB applications.

A Survey of Performance Enhancement Techniques of Antipodal Vivaldi Antenna

“…The straight-line present in between two endpoints of elliptical shape if extended it will be modified to a circular shape as shown in figure 6(b). This circular shape AVA provides the same radiation pattern in both E and H plane and improves impedance matching [51]. Further, it improves impedance bandwidth to 25:1 as reported in [39].…”

Constant gain modified antipodal vivaldi antenna with rake‐like wires operating over 3.1–10.6 GHz

“…The Vivaldi antenna and its modified versions – are common types of the UWB antennas due to its planar geometry, wide operating frequency range, directive radiation pattern, and capability of high gain. Similar to the case of the other UWB antenna types, the Vivaldi antenna and its modified versions have usually lower gain levels at the lower frequencies of the operating bandwidth compared to the higher frequencies …”

Postwall Slotline and Its Application in Design of Short-Pulse Tapered Slot Antennas

“…In the reported literatures, diverse tapered profiles, such as the common exponential [18] and linear [19] profiles combined with the subsequently emerged Fermi [20], hyperbolic [21], elliptic [22], and Gaussian [23] profiles, have been presented to design TSAs and their performance has been investigated. The above referred profiles are related to respective features and thus the choice depends on the specific application.…”