![]() Yu (1991), High frequency scattering from trihedral corner reflectors and other benchmark targets: SBR versus experiment, IEEE T. (1989), Advanced Engineering Electromagnetics, John Wiley & Sons, New York.īaldauf, J., S.-W. (1987), Consequences of nonorthogonality on the scattering properties of dihedral reflectors, IEEE T. Due to the high cost of deploying ACRs in the fields, the physical optics method seems to provide a viable way to choose appropriate ACRs.Īnderson, W.C. Its RCS values, however, are the least of the three. The triangular pyramidal trihedral ACR is the most geometrically stable ACR, and has the highest tolerance towards incident radar ray’s deviation. Our calculation suggests that the square trihedral ACR produces the largest RCS but least tolerance towards incident radar ray’s deviation from optimal angle. Based on physical optics methods, via calculating the radar cross section (RCS) values (the higher the value, the better the detectability), the current study tested three ACRs, i.e., triangular pyramidal, rectangular pyramidal and square trihedral ACRs. The choice of the most appropriate ones has recently attracted scholarly attentions. Optical corner reflectors in the form of colored glass with many tetrahedron-shaped depressions are used as a means of signaling in automotive transport and in daily life.Artificial corner reflectors (ACRs) are widely applicable in monitoring terrain change via interferometric synthetic aperture radar (InSAR) remote sensing techniques. Examples of their use include navigation, the measurement of distances and the speed of light in the atmosphere, and lunar-ranging experiments. ![]() Optical corner reflectors became widespread after the advent of the laser. To obtain an omnidirectional corner reflector, a system of several such prisms is used. Such a corner reflector has a high S effbecause the ratio a/λ is large. ![]() An optical corner reflector is a small trihedral prism made of transparent glass its faces, which have an area of about 1 cm 2, are coated with a thin metallic layer. The action of a corner reflector in the optical range is based on the same principle as that of a radar corner reflector. The identification of a radar image from a corner reflector is facilitated by making one of the reflector’s faces vibrate, thereby modulating the intensity of the reflected signal at the site of reception. Corner reflectors are installed on, for example, navigational buoys, lifeboats, and the approaches to airfields. The faces of a corner reflector are often made of metallic mesh in order to reduce its weight. To obtain an omnidirectional reflector, eight corner reflectors are combined. For example, when a = 1 m and λ = 1.5 m, S eff = 17 m 2, which corresponds to the effective reflecting surface of a small aircraft, such as a fighter when α = 1 m and λ = 10 cm, S eff = 3.77 × 10 3 m 2, which is equivalent to the effective reflecting surface of a large oceangoing vessel.Ī corner reflector is an effective reflector within the limits of the first octant of a sphere. For a corner reflector with square faces the maximum target cross section S eff max = 12π a 4/λ 2, and for one with triangular faces S eff = 4π a 4/3λ 2, where a is the side of the square or the leg of the right triangle and λ is the wavelength. The highest value of S eff is achieved when the incident ray coincides with the bisector of the trihedral angle. ![]() The value of S eff is a function of the angle of incidence θ and varies in proportion to cos θ. For rays that arrive within a substantial solid angle, a corner reflector is similar to a mirror. A ray that is incident on one of the surfaces at a small angle θ to the bisector of the trihedral angle is returned in the direction of the radiation source after triple reflection. Radar corner reflectors consist of three mutually perpendicular metallic surfaces, usually of rectangular or triangular shape. Corner reflectors are used in radar and in optical detection and ranging. The target cross section S eff is the area of a hypothetical flat target having the same reflection coefficient in a specified direction as does the given target. An artificial ranging target with a large target cross section that is weakly dependent on the angle of incidence of electromagnetic waves.
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