Energy-Efficient Dynamic Directional Modulation With Electrically Small Antennas

Adam Narbudowicz,Max J. Ammann,Nicola Marchetti,Abel Zandamela

doi:10.1109/lawp.2022.3141212

Abstract

This letter proposes a compact and energy-efficient directional modulation scheme for small and power constrained devices (e.g., Internet of Things wireless sensors). The scheme uses a uniform circular array of monopole antennas, with a single radiofrequency chain and antenna active at a time. The antennas can be located in close proximity, offering significant size reduction. Furthermore, the scheme was demonstrated to operate successfully with an array of 0.6 λ diameter. The system does not generate additional artificial noise, limiting interference to other systems. Finally, the antenna switching sequence can be randomly generated and without fine-tuned synchronization with the transmitter.

Highlights

PHYSICAL LAYER SECURITY is an area of growing interest in modern wireless communications, as it offers increased secrecy and privacy of genuinely open radio transmissions
This solution is of special interest for small platforms, such as Internet of Thing (IoT) devices or Wireless Sensor Networks, where the compactness of the platform and power consumption constraints limit the use of sophisticated state-ofthe-art cryptography executed in higher layers of the telecommunication stack
We propose a simple Directional Modulation (DM) scheme aimed for

Summary

INTRODUCTION

PHYSICAL LAYER SECURITY is an area of growing interest in modern wireless communications, as it offers increased secrecy and privacy of genuinely open radio transmissions. The technique interprets the constellation scrambling as an artificial noise that has a null in the direction of the legitimate receiver Even though both solutions succeeded in antenna miniaturization, they require individual amplitude and phase control over each port This requires additional RF chains, which increases complexity and power consumption of the device. The use of a single RF chain allows cost saving and improves energy efficiency over traditional DM systems with multiple RF chains [9] It does not introduce additional artificial noise in undesired directions. Throughout this letter, the direction of the intended receiver is denoted as BOB, which is a reference to the traditional terms Alice and Bob used in cryptography to denote respectively the transmitter and receiver of the encrypted message

PROPOSED SYSTEM

IDEAL ARRAY

EXPERIMENTAL VALIDATION

CONCLUSION