Search results
Results from the WOW.Com Content Network
[12] [13] For example, the "receiving pattern" (sensitivity to incoming signals as a function of direction) of an antenna when used for reception is identical to the radiation pattern of the antenna when it is driven and functions as a radiator, even though the current and voltage distributions on the antenna itself are different for receiving ...
Point-to-multipoint wireless networks employing directional antennas are affected by the hidden node problem (also called hidden terminal) in case they employ a CSMA/CA medium access control protocol. The negative impact of the hidden node problem can be mitigated using a time-division multiple access (TDMA) based protocol or a polling protocol ...
The radio horizon is the locus of points at which direct rays from an antenna are tangential to the surface of the Earth. If the Earth were a perfect sphere without an atmosphere, the radio horizon would be a circle. The radio horizon of the transmitting and receiving antennas can be added together to increase the effective communication range.
Patch antenna gain pattern. A directional antenna or beam antenna is an antenna which radiates or receives greater radio wave power in specific directions. Directional antennas can radiate radio waves in beams, when greater concentration of radiation in a certain direction is desired, or in receiving antennas receive radio waves from one specific direction only.
In modern usage, "MIMO" specifically refers to a class of techniques for sending and receiving more than one data signal simultaneously over the same radio channel by exploiting the difference in signal propagation between different antennas (e.g. due to multipath propagation). Additionally, modern MIMO usage often refers to multiple data ...
Radio propagation is the behavior of radio waves as they travel, or are propagated, from one point to another in vacuum, or into various parts of the atmosphere. [1]: 26‑1 As a form of electromagnetic radiation, like light waves, radio waves are affected by the phenomena of reflection, refraction, diffraction, absorption, polarization, and scattering. [2]
A few of the simplest indoor antennas are described below, but a great variety of designs and types exist. Many have a dial on the antenna with a number of different settings to alter the antenna's reception pattern. This should be rotated with the set on while looking at the screen until the best picture is obtained.
Antennas can be classified in various ways, and various writers organize the different aspects of antennas with different priorities, depending on whether their text is most focused on specific frequency bands; or antenna size, construction, and placement feasibility; or explicating principles of radio theory and engineering that underlie ...