Quantum-Correlated Noise Radar with Phase-Sensitive Amplification
Jonathan N. Blakely · 2021
A form of quantum-correlated noise radar that uses phase-sensitive amplification is analyzed. Both the transmitted field and the retained reference field are subject to amplification of a single field quadrature. The receiver uses homodyne detection to correlate the quadratures of the retained field and received radiation. This approach is intended to avoid issues in previous implementations of quantum noise radar such as a weak signal field or quantum noise associated with phase-insensitive amplification and heterodyne detection. The performance of quantum-correlated noise radar with phase-sensitive amplification is quantified in terms of the Bhattacharyya distance which sets a bound on the probability of detection errors in a symmetric detection scenario. The resulting bound is compared to some classical-state radar benchmarks. Despite making best-case-scenario assumptions for the quantum radar and ignoring practical difficulties with implementation, no advantage over classical noise radar with a bright retained field appears in the Bhattacharyya distance.