Antipodal Vivaldi Antenna Design and Applications

Antipodal Vivaldi antennas are wideband travelling-wave devices characterised by exponentially tapered opposing metal flares that enable ultrawide impedance bandwidths, high gain and end-fire radiation patterns. Their planar form factor and scalable geometry make them attractive for a broad range of wireless and sensing applications, from ground-penetrating radar and through-wall imaging to 5G millimetre-wave communications and radar cross-section reduction. Design advances have focused on miniaturisation, pattern stability, polarisation purity and stealth functionality. Techniques such as slot loading, corrugation, dielectric lenses and metasurfaces have been employed to tailor radiation characteristics, suppress sidelobes and reduce radar signatures without sacrificing bandwidth. Emerging fabrication technologies and computational optimisation methods have accelerated the translation of novel architectures into compact, high-performance antennas suitable for both commercial and defence contexts.

Research from Nature Portfolio

A recent investigation introduced a miniaturised antipodal Vivaldi antenna array integrating a hybrid diffusive-absorptive metasurface. Periodic elliptical slots at the edges of each element and a dielectric lens yielded an ultrawide impedance bandwidth spanning 4.5 to 50 GHz and a peak gain of 12.7 dBi at 35 GHz. By employing a Minkowski-shaped ground metasurface that combines multielement phase cancellation and electromagnetic absorption, a low-observable array was realised. The 4×4 configuration achieved more than 10 dB radar cross-section reduction across 5 to 50 GHz for both polarisations, demonstrating that stealth performance can be integrated into wideband, high-gain Vivaldi architectures without degrading their radiating efficiency or bandwidth.

Antipodal Vivaldi Antenna Design and Applications publication trend

The graph below shows the total number of articles in antipodal vivaldi antenna design and applications across all publications each year (not limited to Nature Index journals).

Technical terms

Ultrawideband (UWB): A class of antennas or signals covering a very large fractional bandwidth, often exceeding 500 MHz or more than 20 percent of the centre frequency.

Impedance bandwidth: The range of frequencies over which an antenna’s input impedance remains within acceptable limits, typically defined by a threshold return loss (e.g. –10 dB).

Gain: A measure of how effectively an antenna directs radiated power in a given direction, expressed in decibels relative to an isotropic source (dBi).

Metasurface: A two-dimensional engineered structure composed of subwavelength elements that can manipulate electromagnetic wavefronts by imparting phase, amplitude or polarization changes.

Radar cross section (RCS): A parameter quantifying the detectability of an object by radar, proportional to the power scattered back toward the radar receiver.

Near-field: The region close to an antenna (typically within a few wavelengths) where reactive fields dominate and radiation characteristics differ from those in the far-field.

References

1. Analysis of Near-Field Characteristics on Improved Structures of Double-Slot Antipodal Vivaldi Antenna. Sensors (2024).
2. Design of a miniaturized ultrawideband and low scattering antipodal vivaldi antenna array. Scientific Reports (2021).
3. An Ultra-Wideband Vivaldi Antenna System for Long-Distance Electromagnetic Detection. Applied Sciences (2022).
4. A Highly Compact Antipodal Vivaldi Antenna Array for 5G Millimeter Wave Applications. Sensors (2021).