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Omnidirectional Antenna - Horizontal And Vertical Radiation Patterns
Omnidirectional refers to the notion of existing in every direction. Omnidirectional devices include: * Omnidirectional antenna, an antenna that radiates equally in all directions * VHF omnidirectional range, a type of radio navigation system for aircraft * Omnidirectional camera, a camera that can see all 360 degrees around it * Omnidirectional treadmill, a treadmill that allows a person to walk in any direction without moving * Omnidirectional microphone, a microphone that can hear from all directions * Mecanum wheel A Mecanum wheel is an wikt:omnidirectional, omnidirectional wheel design for a land-based vehicle to move in any direction. It is sometimes called the Swedish wheel or Ilon wheel after its inventor, Bengt Erland Ilon (1923–2008), who conceived ..., a specially designed wheel that allows movement in any direction, such as that used by many robots in the RoboCup Small Size League * Wingless Electromagnetic Air Vehicle, an electrically operated vehicle that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Omnidirectional Antenna
In radio communication, an omnidirectional antenna is a class of antenna (electronics), antenna which radiates equal radio power in all directions perpendicular to an Cartesian coordinate system, axis (azimuthal directions), with power varying with angle to the axis (elevation angle), declining to zero on the axis. When graphed in three dimensions ''(see graph)'' this radiation pattern is often described as ''doughnut-shaped''. This is different from an isotropic radiator, isotropic antenna, which radiates equal power in ''all'' directions, having a ''spherical'' radiation pattern. Omnidirectional antennas oriented vertically are widely used for nondirectional antennas on the surface of the Earth because they radiate equally in all horizontal directions, while the power radiated drops off with elevation angle so little radio energy is aimed into the sky or down toward the earth and wasted. Omnidirectional antennas are widely used for radio broadcasting antennas, and in mobile ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
VHF Omnidirectional Range
Very High Frequency Omnidirectional Range Station (VOR) is a type of short-range VHF radio navigation system for aircraft, enabling aircraft with a VOR receiver to determine the azimuth (also radial), referenced to magnetic north, between the aircraft to/from fixed VOR ground transmitter, radio beacons. VOR and the first DME(1950) system (referenced to 1950 since different from today's DME/N) to provide the slant range distance, were developed in the United States as part of a U.S. civil/military program for Aeronautical Navigation Aids in 1945. Deployment of VOR and DME(1950) began in 1949 by the U.S. CAA (Civil Aeronautics Administration). ICAO standardized VOR and DME(1950) in 1950 in ICAO Annex ed.1. Frequencies for the use of VOR are standardized in the very high frequency (VHF) band between 108.00 and 117.95 MHz Chapter 3, Table A. To improve azimuth accuracy of VOR even under difficult siting conditions, Doppler VOR (DVOR) was developed in the 1960s. VOR is accordi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Omnidirectional Camera
In photography, an omnidirectional camera (from "omni", meaning all), also known as 360-degree camera, is a camera having a field of view that covers at least a full circle ( 360°) in the horizontal plane, up to a full sphere ( 1 spat). Omnidirectional cameras are important in areas where large visual field coverage is needed, such as in panoramic photography and robotics. Overview A camera normally has a field of view that ranges from a few degrees to, at most, 180°. This means that it captures, at most, light falling onto the camera focal point through a hemisphere. In contrast, an ''ideal'' omnidirectional camera captures light from all directions falling onto the focal point, covering a full sphere. In practice, however, most omnidirectional cameras do not cover the entire sphere. Many cameras which are referred to as omnidirectional cover the full 360° along the equator of the sphere but exclude the top and bottom. In the case that they do cover the full sphere, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Omnidirectional Treadmill
An omnidirectional treadmill (ODT) is a mechanical device, similar to a typical treadmill, that allows a person to perform locomotive motion in any direction, allowing for 360 degrees of movement. The ability to move in any direction is how these treadmills differ from their basic counterparts (that permit only unidirectional locomotion). Omnidirectional treadmills are employed in immersive virtual environment implementations to allow unencumbered movement within the virtual space. Advantages to pairing an ODT with an immersive virtual environment include: * Natural navigational movement of the system user within the enclosure while still providing contextual cueing which simulate physical traversal through the virtual terrain * Reverting immersive navigation tasks from hand-based (mouse, joystick) to mentally hard-wired whole body (leg) based * Enhancing immersion by providing a whole-body experience that begins at the soles of the feet and ends at the top of the head * Fa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microphone
A microphone, colloquially called a mic (), or mike, is a transducer that converts sound into an electrical signal. Microphones are used in many applications such as telephones, hearing aids, public address systems for concert halls and public events, motion picture production, live and recorded audio engineering, sound recording, two-way radios, megaphones, and radio and television broadcasting. They are also used in computers and other electronic devices, such as mobile phones, for recording sounds, speech recognition, Voice over IP, VoIP, and other purposes, such as Ultrasonic transducer, ultrasonic sensors or knock sensors. Several types of microphone are used today, which employ different methods to convert the air pressure variations of a sound wave to an electrical signal. The most common are the dynamic microphone, which uses a coil of wire suspended in a magnetic field; the condenser microphone, which uses the vibrating Diaphragm (acoustics), diaphragm as a capacitor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mecanum Wheel
A Mecanum wheel is an wikt:omnidirectional, omnidirectional wheel design for a land-based vehicle to move in any direction. It is sometimes called the Swedish wheel or Ilon wheel after its inventor, Bengt Erland Ilon (1923–2008), who conceived of the concept while working as an engineer with the Sweden, Swedish company Mecanum AB, and patented it in the United States on November 13, 1972. It consists of a series of rubberized external rollers set at a 45° angle to the wheel. Each wheel is independently-driven, and the direction of travel is dependent on the interaction between the directions each wheel is driven in relative to the others. Uses include forklifts which require very tight maneuvering, autonomous robots, and wheelchairs. Design The Mecanum wheel is a form of tireless wheel, with a series of rubberized external rollers obliquely attached to the whole circumference of its rim (wheel), rim. These rollers typically each have an axis of rotation at 45° to the wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
