The quantum radar cross section (QRCS) is a measure of how electromagnetically “large” an object appears to a quantum radar. The fundamental mechanism that creates the return response is the interaction between the atomic electric dipole moments and the incoming photon. This paper derives the QRCS equation considering the effect of photon polarization in this interaction, as well as providing a means to study bistatic radar geometries. It is found that under normal circumstances, polarization plays no role in the target response. However, if the target's atomic dipoles are all aligned in one particular direction, such as if the object is in a strong uniform or slowly varying field, polarization has a significant effect on the response by allowing us to “steer” the location of a null to any observation angle desired. Furthermore, scattering can be suppressed in a very large range of scattering angles (not just one) if the polarization of the object and photon are chosen judiciously. It will be shown that this effect is unique to quantum radar and has no classical counterpart.
The quantum radar cross section (QRCS) is a measure of how electromagnetically “large” an object appears to a quantum radar. The fundamental mechanism that creates the return response is the interaction between the atomic electric dipole moments and the incoming photon. This paper derives the QRCS equation considering the effect of photon polarization in this interaction, as well as providing a means to study bistatic radar geometries. It is found that under normal circumstances, polarization plays no role in the target response. However, if the target's atomic dipoles are all aligned in one particular direction, such as if the object is in a strong uniform or slowly varying field, polarization has a significant effect on the response by allowing us to “steer” the location of a null to any observation angle desired. Furthermore, scattering can be suppressed in a very large range of scattering angles (not just one) if the polarization of the object and photon are chosen judiciously. It will be shown that this effect is unique to quantum radar and has no classical counterpart.
In this paper, we discuss the effect that photon polarization has on the quantum radar cross section (QRCS) during the special case scenario of when the target is enveloped in either a uniform electric field or magnetic field and all of its atomic electric/magnetic dipole moments become aligned (target polarization). This target polarization causes the coupling between the photon and the matter to change and alter the scattering characteristics of the target. Most notably, it causes scattering to be very near zero at a specified angle. We also investigate the relationship between electric and magnetic types of coupling and find that the electric contribution dominates the QRCS response.
In radar, the amount of returns that an object sends back to the receiver after
being struck by an electromagnetic wave is characterized by what is known as the
radar cross section, denoted by � typically. There are many mechanisms that affect
how much radiation is reflected back in the receiver direction, such as reflectivity,
physical contours and dimensions, attenuation properties of the materials, projected
cross sectional area and so on. All of these characteristics are lumped together in a
single value of �, which has units of m2. Stealth aircrafts for example are designed
to minimize its radar cross section and return the smallest amount of radiation
possible in the receiver direction.
A new concept has been introduced called quantum radar, that uses correlated
quantum states of photons as well as the unique properties of quantum mechanics
to ascertain information on a target at a distance. At the time of writing this
dissertation, quantum radar is very much in its infancy. There still exist fundamental
questions about the feasibility of its implementation, especially in the microwave
spectrum. However, what has been theoretically determined, is that quantum radar
has a fundamental advantage over classical radar in terms of resolution and returns
in certain regimes.
Analogous to the classical radar cross section (CRCS), the concept of the
quantum radar cross section (QRCS) has been introduced. This quantity measures
how “large” an object looks to a quantum radar be describing how a single photon, or
small cluster of photons scatter off of a macroscopic target. Preliminary simulations
of the basic quantum radar cross section equation have yielded promising results
showing an advantage in sidelobe response in comparison to the classical RCS. This
document expands upon this idea by providing insight as to where this advantage expanding upon the theory.
The expanded theory presented in this document includes re-deriving the QRCS
formula to be a general bistatic formula, as the current equation is only valid for
monostatic radar geometries. This re-derivation process also leads to the addition of
terms that capture the effect of photon polarization, something that is not properly
taken into account in the current literature. Most importantly, a new formulation
of the QRCS formula will be derived that includes writing the equation in terms
of Fourier transforms. This has a profound impact on the analysis of the theory
of the QRCS as it allows for the derivation of closed form solutions of certain
geometries, something that has never been possible due to the form of the current
QRCS equation. All together, this document will provide a complete and general
theory of the QRCS.
After deriving the necessary equations, there will be extensive work in the
utilization of these equations in deriving geometry dependent responses and comparing
the closed form solutions to the classical solutions as well as comparing the
solutions to the numerical simulations.
The current literature relies exclusively on numerical simulations…
The quantum radar cross section (QRCS) describes how much return one gets when illuminating an object with a handful of photons. However, the previous studies mainly focused on the monostatic scattering of quantum radar. In this study, in response to the four key questions raised by ourselves in bistatic quantum radar cross section (BIQRCS), we calculate and analyze the BIQRCS for the typical tow-dimensional plate. First, as mentioned by Brandsema, the further derived analytical solution for the rectangular plate is obtained. In addition, the influence of incident frequency and the number of photons on the BIQRCS for the plate were obtained. Besides, we first reveal that the envelope curves of sidelobes in BIQRCS at the given incidence display the invariance in frequency. Finally, we show some comparison results among the BIQRCS, classical radar cross section (CRCS), and monostatic QRCS for the plate and find the advantage of sidelobe of the BIQRCS in given direction. We anticipate that these research results will find use in the detection and discrimination of stealthy platforms.
With the development of quantum radar technology, the interaction of photons and targets has gradually become a new hotspot. Quantum radar cross section (QRCS) is an important parameter fon describing the visibility of the target illuminated by light quantum. #br#According to the conservation of energy and the finite element method, the expression of QRCS derived by Marco Lanzagorta is extended, which can be applied to QRCS calculations of non-planar convex targets. As the surface elements of the target have different incident and scattering angles, the integral equation can give a higher calculation accuracy and is suitable for bistatic or multistatic situations. #br#The distribution pattern of the target’s atoms is varied. Using the interatomic distance as the only parameter to describe the atomic distribution is inaccurate. In this paper the metal atomic lattice is considered. Simulation of the QRCS that is composed of three kinds of metal atomic lattices (face-centered cubic, body-centered cubic and hexagonal close-packed lattices) with different atomic distributions has been made. The hexagonal close-packed lattice with asymmetrical distribution for different azimuth angles is discussed. Simulation result shows that with different arrangement of atoms, the main lobe of the target QRCS is basically unchanged, while the quantum side-lobes of the target with sparsely arranged atoms are much more significant. This reveals a different characteristic of QRCS, and provides theoretic basis for quantum radar and stealth technique researches.
We study two-photon entangled states for quantum radar cross section (QRCS), which is an extension of a single-photon QRCS formula. Since signal-idler entanglement does not provide any enhancement of the QRCS [Brandsema's PhD Thesis (2017)], we focus on signal-signal entanglement and derive the corresponding biphoton QRCS. We show that it can provide an enhancement over the single-photon QRCS and two-photon separable QRCS, where the performance is evaluated for various two-dimensional target geometries in monostatic/bistatic configurations. Furthermore, using the double-Gaussian approximation, we derive QRCS formula for biphoton states with arbitrary degree of entanglement and compute the resulting scattering patterns.
Quantum radar is a new detection technology based on the mechanism of quantum physics and is promising for enhancing radar target detection capability. In this letter, the quantum radar equation is established based on the traditional radar equation; meanwhile, how the quantum radar cross section (QRCS) influences target detection performance and how QRCSs for some typical targets distribute are investigated via simulations. Simulation results demonstrate that the signal-to-noise ratio increases with the QRCS, the peak values of side-lobes of the QRCS for the cylinder surface fluctuate little, and the QRCS for corner reflectors almost exhibits no variations in a wide range of incident angles. The results listed above can benefit the signal design and performance evaluation of quantum radar as well as the design of quantum stealthy targets.