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Antenna Equivalent Radius
The equivalent radius of an Antenna (radio), antenna electrical conductor is defined as:David M. Drumheller K3WQ, ''The Antenna Equivalent Radius: A Model for Non-Circular Conductors'', QEX, American Radio Relay League, Newington CT, 2017 March/April pp. 10ff. r_e = \exp\left\ where \scriptstyle\ell denotes the conductor's circumference, \scriptstyle is the length of the circumference, \scriptstyle and \scriptstyle are Euclidean vector, vectors locating points along the circumference, and \scriptstyle and \scriptstyle are differentials segments along it. The equivalent radius allows the use of analytical formulas or computational or experimental data derived for antennas constructed from small conductors with uniform, ''circular'' cross-sections to be applied in the analysis of antennas constructed from small conductors with uniform, ''non-circular'' cross-sections. Here "small" means the largest dimension of the cross-section is much less than the wavelength \scriptstyle. Formu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antenna (radio)
In radio-frequency engineering, an antenna (American English) or aerial (British English) is an electronic device that converts an alternating current, alternating electric current into radio waves (transmitting), or radio waves into an electric current (receiving). It is the interface between radio waves Radio propagation, propagating through space and electric currents moving in metal Electrical conductor, conductors, used with a transmitter or receiver (radio), receiver. In transmission (telecommunications), transmission, a radio transmitter supplies an electric current to the antenna's Terminal (electronics), terminals, and the antenna radiates the energy from the current as electromagnetic radiation, electromagnetic waves (radio waves). In receiver (radio), reception, an antenna intercepts some of the power of a radio wave in order to produce an electric current at its terminals, that is applied to a receiver to be amplifier, amplified. Antennas are essential components ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Skin Effect
In electromagnetism, skin effect is the tendency of an alternating current, alternating electric current (AC) to become distributed within a Conductor (material), conductor such that the current density is largest near the surface of the conductor and decreases exponentially with greater depths in the conductor. It is caused by opposing eddy currents induced by the changing magnetic field resulting from the alternating current. The electric current flows mainly at the ''skin'' of the conductor, between the outer surface and a level called the skin depth. Skin depth depends on the frequency of the alternating current; as frequency increases, current flow becomes more concentrated near the surface, resulting in less skin depth. Skin effect reduces the effective cross-section of the conductor and thus increases its effective electrical resistance, resistance. At 60 Hertz, Hz in copper, skin depth is about 8.5 mm. At high frequencies, skin depth becomes much smaller. Increased ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triangular Conductor Antenna Cross-section
A triangle is a polygon with three corners and three sides, one of the basic shapes in geometry. The corners, also called ''vertices'', are zero-dimensional points while the sides connecting them, also called ''edges'', are one-dimensional line segments. A triangle has three internal angles, each one bounded by a pair of adjacent edges; the sum of angles of a triangle always equals a straight angle (180 degrees or π radians). The triangle is a plane figure and its interior is a planar region. Sometimes an arbitrary edge is chosen to be the ''base'', in which case the opposite vertex is called the ''apex''; the shortest segment between the base and apex is the ''height''. The area of a triangle equals one-half the product of height and base length. In Euclidean geometry, any two points determine a unique line segment situated within a unique straight line, and any three points that do not all lie on the same straight line determine a unique triangle situated within a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Square Conductor Antenna Cross-section
In geometry, a square is a regular polygon, regular quadrilateral. It has four straight sides of equal length and four equal angles. Squares are special cases of rectangles, which have four equal angles, and of rhombuses, which have four equal sides. As with all rectangles, a square's angles are right angles (90 degree (angle), degrees, or Pi, /2 radians), making adjacent sides perpendicular. The area of a square is the side length multiplied by itself, and so in algebra, multiplying a number by itself is called square (algebra), squaring. Equal squares can tile the plane edge-to-edge in the square tiling. Square tilings are ubiquitous in tiled floors and walls, graph paper, image pixels, and game boards. Square shapes are also often seen in building floor plans, origami paper, food servings, in graphic design and heraldry, and in instant photos and fine art. The formula for the area of a square forms the basis of the calculation of area and motivates the search for methods for s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flat Thin Conductor Antenna Cross-section
Flat or flats may refer to: Architecture * Apartment, known as a flat in the United Kingdom, Ireland, and other Commonwealth countries Arts and entertainment * Flat (music), a symbol () which denotes a lower pitch * Flat (soldier), a two-dimensional toy soldier made of tin or plastic * Flat (theatre), a flat piece of theatrical scenery * Flat, a leading type of wordplay, as identified by the National Puzzlers' League * '' Flat!'' (2010), an Indian film * Flats (band), an English band * Flats (comics), the first stage in the comic coloring process Footwear * Flats, footwear which is not high-heeled * Ballet flats, derived from ballet shoes, for casual wear as well as dancing * Ballet shoes (also known as ballet slippers), often referred to as "flats" or "flat shoes" * Racing flats, lightweight shoes used primarily for running a race Geography Landforms * Flat (landform), a relatively level area within a region of greater relief * Mudflat, intertidal wetland with a substr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrical Conductor
In physics and electrical engineering, a conductor is an object or type of material that allows the flow of charge (electric current) in one or more directions. Materials made of metal are common electrical conductors. The flow of negatively charged electrons generates electric current, positively charged holes, and positive or negative ions in some cases. In order for current to flow within a closed electrical circuit, one charged particle does not need to travel from the component producing the current (the current source) to those consuming it (the loads). Instead, the charged particle simply needs to nudge its neighbor a finite amount, who will nudge ''its'' neighbor, and on and on until a particle is nudged into the consumer, thus powering it. Essentially what is occurring is a long chain of momentum transfer between mobile charge carriers; the Drude model of conduction describes this process more rigorously. This momentum transfer model makes metal an ideal choice f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
