spherical antenna
1Antenna measurement — techniques refers to the testing of antennas to ensure that the antenna meets specifications or simply to characterize it. Typical parameters of antennas are gain, radiation pattern, beamwidth, polarization, and impedance.The antenna pattern is… …
2Antenna gain — is defined as the ratio of the radiation intensity of an antenna in a given direction, to the intensity of the same antenna as it radiates in all directions (isotropically). Since the radiation intensity of an isotropically radiated power is… …
3Parabolic antenna — A parabolic satellite communications antenna at Erdfunkstelle Raisting, the biggest facility for satellite communication in the world, in Raisting, Bavaria, Germany. It has a Cassegrain type feed. A parabolic antenna is an antenna that uses a… …
4Horn antenna — Pyramidal microwave horn antenna, with a bandwidth of 0.8 to 18 GHz. A coaxial cable feedline attaches to the connector visible at top. This type is called a ridged horn; the curving fins visible inside the mouth of the horn increase the antenna… …
5Omnidirectional antenna — The radiation pattern of a simple omnidirectional antenna, a vertical half wave dipole antenna. In this graph the antenna is at the center of the donut . Radial distance from the center represents the power radiated in that direction. The power… …
6High-gain antenna — The high gain antenna (HGA) is an antenna with a focused, narrow radiowave beam width. This narrow beam width allows more precise targeting of the radio signal also known as a directional antenna. Most commonly referred to during space missions,… …
7Wardenclyffe Tower — (1901 ndash; 1917) also known as the Tesla Tower, was an early wireless telecommunications aerial tower designed by Nikola Tesla and intended for commercial trans Atlantic wireless telephony, broadcasting, and to demonstrate the transmission of… …
8Mir — This article is about the Soviet/Russian space station. For other uses, see Mir (disambiguation). Mir …
9telescope — /tel euh skohp /, n., adj., v., telescoped, telescoping. n. 1. an optical instrument for making distant objects appear larger and therefore nearer. One of the two principal forms (refracting telescope) consists essentially of an objective lens… …
10Parabolic reflector — Parallel waves coming in to a parabolic mirror are focused at a point F A parabolic reflector (or dish or mirror) is a reflective device used to collect or project energy such as light, sound, or radio waves. Its shape is that of a circular… …
