Design of a Single-Element Dynamic Antenna for Secure Wireless Applications

TL;DR

This paper presents a novel single-element dynamic antenna that creates a secure spatial region for wireless transmission by dynamically altering radiation patterns, enhancing security without complex system modifications.

Contribution

The paper introduces a new single-element dynamic antenna design that generates static and dynamic radiation patterns for secure wireless communication, supported by theoretical analysis and experimental validation.

Findings

Secure region narrows with higher modulation order

Demonstrated ability to steer the secure region experimentally

High throughput maintained within the secure region

Abstract

We introduce a new technique for secure wireless applications using a single dynamic antenna. The dynamic antenna supports a constantly changing current distribution that generates a radiation pattern that is static in a desired direction and dynamic elsewhere, thereby imparting additional modulation on the signal and obscuring information transmitted or received outside of the secure spatial region. Dynamic currents are supported by a single feed that is switched between separate ports on a single antenna, generating two different radiation patterns. We introduce the theoretical concept by exploring an ideal complex dynamic radiation pattern that remains static in a narrow desired direction and is dynamic elsewhere. The impact on the transmission of information is analyzed, showing that the secure region narrows as the modulation order increases, and design constraints on the spatial width of the secure region as a function of modulation format are determined. We design and analyze a 2.3 GHz two-state dynamic dipole antenna and experimentally demonstrate secure wireless transmission. We show the ability to steer the secure region experimentally, and to maintain high throughput in the secure region while obscuring the information elsewhere. Our approach introduces a novel single-element technique for secure wireless applications that can be used independently from the rest of the wireless system, essentially operating as a $``$black box$"$ for an additional layer of security.