Multiantenna Quantum Backscatter Communications

Abstract

Abstract-Quantum illumination (QI) is a revolutionary photonic quantum sensing paradigm that enhances the sensitivity of photodetection in noisy and lossy environments. In this paper, we propose to use QI in a quantum backscatter communication (QBC), with the aim of increasing the receiver sensitivity beyond the limits of its classical counterpart. One of the practical challenges in microwave QI is the slow rate at which the entangled microwave modes can be generated. Here, we propose to mitigate this problem by using a multiple-input multipleoutput antenna system to synthetically increase the number of efficiently-distinguishable modes in the QBC context.

Quantum Backscatter Communication: A New Paradigm

“…The latter allows to displace to zero the phasesensitive correlations of one of the hypothesis. 7 We discuss the performance in the different QBC schemes in the N Z ≫ 1, N S ≪ 1, τ N Z ≪ 1, ε ≪ 1 limit. a) PAM: The SFG-RX achieves a 6 dB gain in the EPE with respect the classical BC.…”

“…Therefore, in order to apply the qubit approximation, we need to divide the M signal-idler pair of modes in M/K subsets, such that K|C(0)| 2 ≪ 1, and apply the RX to theK pair of modes at a time [8]. 7 [8] applies also two TMSO after the SFG circuit. This allows to have in every cycle n E ) , with φ ∈ {0, π/2, π, 3π/2}, where the TMSOs have the role of the displacements.…”

“…The proposed Quantum Backscatter Communications (QBC) bears close resemblance to the quantum radar in a manner similar to BC being closely related to the classical radar. Our recent work paper [7] has proposed to construct pre-coder beamsplitters and receiver beamforming beam-splitters such that the orthogonal eigen-channels can be accessed using QBC. This paper aims at describing the QBC concept and analyzing its performance in terms of bit error rate (BER).…”

Quantum Backscatter Communication with Photon Number States

“…Quantum entanglement, whereby distant systems exhibit non-local measurement correlations, holds the keys to realizing precision measurements that go beyond the classical shot noise limit. By harnessing these non-classical correlations recent protocols had been developed to detect targets submersed in noisy and lossy environment [6], while recently the same concept was deployed to detect backscattered communication signals in the microwave regime [1], [2]. Moreover, it had been shown that target detection using entangled photon pairs is optimal under the same environmental assumptions [6]- [8].…”

“…Utilizing this valuable resource, our transmitter will be a microwave entanglement generator, where the signal photon is sent to interact with the backscatter antenna, while the idler one will be retained at the receiver. Nevertheless, the probing intervals are limited by the ability of our source to generate independent entangled photon pairs, where for the chosen frequency range the number of generated modes is at most ≈ 10 5 [1].…”