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arXiv · 1903.00101

Receiver Operating Characteristics for a Prototype Quantum Two-Mode Squeezing Radar

David Luong·C. W. Sandbo Chang·A. M. Vadiraj·Anthony Damini·C. M. Wilson·Bhashyam Balaji
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Abstract

We have built and evaluated a prototype quantum radar, which we call a quantum two-mode squeezing radar (QTMS radar), in the laboratory. It operates solely at microwave frequencies; there is no downconversion from optical frequencies. Because the signal generation process relies on quantum mechanical principles, the system is considered to contain a quantum-enhanced radar transmitter. This transmitter generates a pair of entangled microwave signals and transmits one of them through free space, where the signal is measured using a simple and rudimentary receiver. At the heart of the transmitter is a device called a Josephson parametric amplifier (JPA), which generates a pair of entangled signals called two-mode squeezed vacuum (TMSV) at 6.1445 GHz and 7.5376 GHz. These are then sent through a chain of amplifiers. The 7.5376 GHz beam passes through 0.5 m of free space; the 6.1445 GHz signal is measured directly after amplification. The two measurement results are correlated in order to distinguish signal from noise. We compare our QTMS radar to a classical radar setup using conventional components, which we call a two-mode noise radar (TMN radar), and find that there is a significant gain when both systems broadcast signals at -82 dBm. This is shown via a comparison of receiver operator characteristic (ROC) curves. In particular, we find that the quantum radar requires 8 times fewer integrated samples compared to its classical counterpart to achieve the same performance.

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David Luong, C. W. Sandbo Chang, A. M. Vadiraj, Anthony Damini, C. M. Wilson, Bhashyam Balaji. 2019-02-28. Receiver Operating Characteristics for a Prototype Quantum Two-Mode Squeezing Radar. https://doi.org/10.1109/taes.2019.2951213

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