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Monostatic radar cross section (RCS) of a perfectly conducting metal sphere as a function of frequency (calculated by Mie theory). In the low-frequency Rayleigh scattering limit, where the circumference is less than wavelength, the normalized RCS is σ π R 2 ∼ 9 ( k R ) 4 {\displaystyle {\tfrac {\sigma }{\pi R^{2}}}\sim 9(kR)^{4}} .
Rho-Theta methodology is a key component in Area Navigation (RNAV). [1] The term "Rho-Theta" consists of the two Greek letters corresponding to Rho and Theta: [2] [3] [4] Rho (Greek ρ) as a synonym for distance measurement, e.g. Rho would be the equivalent to the English abbreviation "R" for Range
A pencil-beam radar A moving or sweeping pencil-beam radar. In optics, a pencil or pencil of rays, also known as a pencil beam or narrow beam, is a geometric construct (pencil of half-lines) used to describe a beam or portion of a beam of electromagnetic radiation or charged particles, typically in the form of a cone or cylinder.
Definition of angles in the vertical plane of SLAR Geometry of an SLAR SLAR radar at ILA Berlin Air Show. Side-looking airborne radar (SLAR) is an aircraft, [1] or satellite-mounted imaging radar pointing perpendicular to the direction of flight (hence side-looking). [2] A squinted (nonperpendicular) mode is also possible.
The resolution of any radar depends on the width of the beam and the range to the target. For example; a radar with 1 degree beam width and a target at 120 km (75 mi) range will show the target as 2 km (1.2 mi) wide. To produce a 1-degree beam at the most common frequencies, an antenna 1.5 kilometres (0.93 miles) wide is required.
A radar beam scattering off electrons in the ionospheric plasma creates an incoherent scatter return. When an electromagnetic wave is transmitted through the atmosphere, each of the electrons in the ionospheric plasma essentially acts as an antenna excited by the incoming wave, and the wave is re-radiated from the electron.
Beam steering is a technique for changing the direction of the main lobe of a radiation pattern. In radio and radar systems, beam steering may be accomplished by switching the antenna elements or by changing the relative phases of the RF signals driving the elements. As a result, this directs the transmit signal towards an intended receiver.
The radar horizon is a critical area of performance for aircraft detection systems, defined by the distance at which the radar beam rises enough above the Earth's surface to make detection of a target at the lowest level possible.