Performance improvement factors in quantum radar/illumination

In this study, we exploit quantum information processing, the research field focusing on quantum two-mode squeezed (QTMS) radar and quantum illumination (QI), to investigate the qualitative behaviors of entanglement, the entropy of formation, and squeezing in these protocols. We use logarithmic negativity to investigate entanglement between the signal and idler and propose strategies to maintain entanglement at room temperature in both protocols. We also calculate the entanglement, squeezing, and entropy for the QTMS radar when the target is present and the signal is transmitted to the target. In addition, by controlling the squeezing parameter which is a tool to control entanglement, entropy, and squeezing, the performance of the QTMS radar can be improved, so this work shows how it is implemented in practice. In both protocols, entanglement is maintained by considering conditions. Since the squeezing parameter controls both signal and idler power and the correlation between them, therefore, the qualitative behavior of squeezing in the QTMS radar and QI is also studied in this research. The significant result obtained from the QI is that the entanglement maintains at high power, low temperature, and high correlation between signal and idler. In contrast, in the QTMS, the entanglement survives when the correlation and power are low, even at room temperature.