Study and simulation of quantum illumination and its impact on detection

Abstract

Quantum illumination (QI) is a sensing protocol that promises a detection advantage over classical radar in noisy, low-signal environments by exploiting quantum-entangled signal idler pairs. Despite well-established theoretical guarantees, notably a 6 dB improvement in the error exponent over coherent-state classical radar, the practical implications of this advantage in radar engineering terms remain largely unexplored. This thesis evaluates the quantum illumination claim from an electronics engineering perspective, with the dual objective of validating the theoretical physics and translating it into radar-engineering quantities. Three simulation approaches of increasing rigour are implemented and compared: an illustrative radar-oriented demonstration, a physically rigorous Fock-space simulation, and an efficient Gaussian-covariance simulation. All three approaches agree: the implementable correlation receiver delivers approximately 3 dB over an energy-matched classical strategy, consistent with the 6 dB theoretical ceiling established for the optimal joint receiver. A transparent translation framework is then developed, mapping classical radar parameters like range, radar cross-section, transmit power, and system temperature to the quantum physics quantities transmissivity eta and thermal background NB, via the radar equation and the Bose factor. Applying this bridge to realistic microwave scenarios reveals that at X-band frequencies and kilometre-scale ranges, both detectors collapse to chance performance due to catastrophic propagation losses and enormous thermal backgrounds. Yet the quantum-to-classical advantage ratio remains preserved at approximately 2.8 dB throughout, confirming that the quantum advantage is a genuine improvement in detection efficiency rather than a means to detect otherwise undetectable targets, a finding that quantitatively explains why quantum illumination radar has not yet been deployed.