Radio Frequency (RF) & Wireless Design

The Vivaldi antenna is a good wideband antenna that has a horn shape ;

https://en.wikipedia.org/wiki/Vivaldi_antenna

I have made this flat planar PCB antenna after the RFSpace design here :

Grabcad model

RFSpace Planar Ultra WideBand (UWB) 900 MHz to 12 GHz PCB Antenna

This is the RFSpace TSA900-12000 Ultra-Wideband (UWB) PCB Tapered Slot Vivaldi Antenna that covers 900 MHz to 12 GHz. It is based on the common PCB microstrip-fed Vivaldi slot antenna design and is useful for wide spectrum coverage, especially in EMI / EMC testing anechoic chambers. It is useful ...

As Well as the more common 'boxed' style :

Grabcad model

2 to 8 GHz (S-band thru C-band) Dual Ridged Horn 3D-Printed Broadband Antenna

This is a model of a Dual (Vivaldi) Ridged Horn that I modeled from a whitepaper titled "Additive Manufacturing of a Dual-Ridged Horn Antenna" by Budhaditya Majumdar, David Baer, Sudipta Chakraborty, Karu P. Esselle, and Michael Heimlich. (https://www.jpier.org/download/16021503.pdf) This model o...

And the very unusual 3D "flared" version of this antenna too :

Grabcad model

3D Vivaldi Antenna

I have seen many planar Vivaldi Antennas for both vertical and horizontal polarization, but decided to create one that has a true circular polarization. This is the beginning of my efforts. This antenna cannot be made from traditional means very easily from standard manufacturing techniques, but ...

And this very exotic dual polarized version NSI-MI :

Grabcad model

NSI-MI Technologies 2 ~ 18 Ghz Broadband Horn Antenna (BHA) with 15 dBi gain

This is a model of a NSI-MI Technologies 2 ~ 18 Ghz Broadband Horn Antenna (BHA) with 15 dBi gain that uses a dual 2.92 mm connector feeds for both horizontal and vertical polarizations (p/n: ANT-BHA-2-18). The antenna pattern is based upon the familiar Vivaldi waveguide. This is the link : https...

There is an interesting article on Comsol's website on the Vivaldi design analysis here :

https://www.comsol.com/blogs/vivaldi-antenna-design-analysis/

So for those interested in pursing this type of Wideband high gain antenna these are a good start, but here are a couple of videos as well using Ansys HFSS and CST MW Studio;

https://www.youtube.com/watch?v=b3BhnKxBzCI

https://www.youtube.com/watch?v=lyDyJuxckg8