directivity of an antenna
21Sector antenna — OverviewSector antenna is a kind of directional antenna with a sector shaped radiation pattern. In mobile communications, these antennas are typically installed in base station sites for point to multipoint connections.tructure, Materials and… …
22Synthetic aperture radar — (SAR) is a form of radar in which the highly directional (and thus very large) rotating antenna used by conventional radar is replaced with many low directivity small stationary antenna positions scattered over some area near or around the target …
23Phased array — This article is about general theory and electromagnetic phased array. For the ultrasonic and medical imaging application, see phased array ultrasonics. In wave theory, a phased array is a group of antennas in which the relative phases of the… …
24Power dividers and directional couplers — A 10 dB 1.7–2.2 GHz directional coupler. From left to right: input, coupled, isolated (terminated with a load), and transmitted port …
25Isotropic radiator — An isotropic radiator is a theoretical point source of waves which exhibits the same magnitude or properties when measured in all directions. It has no preferred direction of radiation. It radiates uniformly in all directions over a sphere… …
26Wireless 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,… …
27Side lobe — In antenna engineering, side lobes are the lobes of the far field radiation pattern that are not the main beam, where the terms beam and lobe are synonyms. An antenna radiation pattern is more commonly called a beam pattern. The power density in… …
28HRS type antennas — are more or less the standard antenna used for long distance high power shortwave broadcasting (> 1000 km). History of HRS design HRS antennas were discovered during the 1920s, and as such were not originally intended for voice and music… …
29Effective radiated power — In radio telecommunications, effective radiated power or equivalent radiated power (ERP) is a standardized theoretical measurement of radio frequency (RF) energy [cite web title = Abbreviations and Acronyms publisher = Institute for… …
30Voice of Russia — For the blues rock band, see Radio Moscow (band). Russian State Radio Company Voice of Russia Type Radio network …
