Intelligent Reflecting Surface Operation under Predictable Receiver Mobility: A Continuous Time Propagation Model

TL;DR

This paper models IRS operation with predictable receiver movement using a continuous time multipath channel model, optimizing IRS configuration to enhance received power and link reliability without increasing Doppler spread.

Contribution

It introduces a continuous time propagation model for IRS with predictable mobility and demonstrates optimal IRS configurations for power maximization and reliability improvement.

Findings

Maximized received power without increasing Doppler spread.

A small IRS can improve ground-LEO link budget by up to 6 dB.

IRS provides an additional communication path, enhancing link reliability.

Abstract

The operation of an intelligent reflecting surface (IRS) under predictable receiver mobility is investigated. We develop a continuous time system model for multipath channels and discuss the optimal IRS configuration with respect to received power, Doppler spread, and delay spread. It is shown that the received power can be maximized without adding Doppler spread to the system. In a numerical case study, we show that an IRS having the size of just two large billboards can improve the link budget of ground to Low Earth Orbit (LEO) satellite links by up to 6 dB. It also adds a second, almost equivalently strong, communication path that improves the link reliability.