- narrow beam transmitter
- 窄束发射机
Atmospheric Sciences (English-Chinese) dictionary. 2014.
Atmospheric Sciences (English-Chinese) dictionary. 2014.
radar — /ray dahr/, n. 1. Electronics. a device for determining the presence and location of an object by measuring the time for the echo of a radio wave to return from it and the direction from which it returns. 2. a means or sense of awareness or… … Universalium
Radar — For other uses, see Radar (disambiguation). A long range radar antenna, known as ALTAIR, used to detect and track space objects in conjunction with ABM testing at the Ronald Reagan Test Site on Kwajalein Atoll … Wikipedia
telecommunications media — Introduction equipment and systems metal wire, terrestrial and satellite radio, and optical fibre employed in the transmission of electromagnetic signals. Transmission media and the problem of signal degradation Every… … Universalium
History of radar — The history of radar starts with experiments by Heinrich Hertz in the late 19th century that showed that radio waves were reflected by metallic objects. This possibility was suggested in James Clerk Maxwell s seminal work on electromagnetism.… … Wikipedia
navigation — navigational, adj. /nav i gay sheuhn/, n. 1. the act or process of navigating. 2. the art or science of plotting, ascertaining, or directing the course of a ship, aircraft, or guided missile. [1520 30; < L navigation (s. of navigatio) a voyage.… … Universalium
Battle of the Beams — The Battle of the Beams was a period in early World War II when bombers of the German Air Force ( Luftwaffe ) started using radio navigation for night bombing. British scientific intelligence at the Air Ministry fought back with a variety of… … Wikipedia
radio — /ray dee oh /, n., pl. radios, adj., v., radioed, radioing. n. 1. wireless telegraphy or telephony: speeches broadcast by radio. 2. an apparatus for receiving or transmitting radio broadcasts. 3. a message transmitted by radio. adj. 4. pertaining … Universalium
Wireless energy transfer — or wireless power is the transmission of electrical energy from a power source to an electrical load without artificial interconnecting conductors. Wireless transmission is useful in cases where interconnecting wires are inconvenient, hazardous,… … Wikipedia
High-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,… … Wikipedia
Horn 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… … Wikipedia
Parabolic 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… … Wikipedia