File:Dipole antenna standing waves animation 461x217x150ms.gif
Summary
Animation showing <a href="https://en.wikipedia.org/wiki/standing_wave" class="extiw" title="w:standing wave">standing waves</a> on a <a href="https://en.wikipedia.org/wiki/half-wave_dipole_antenna" class="extiw" title="w:half-wave dipole antenna">half-wave dipole antenna</a> driven by a sinusoidal voltage VO from a radio transmitter at its <a href="https://en.wikipedia.org/wiki/resonant_frequency" class="extiw" title="w:resonant frequency">resonant frequency</a>. The oscillating voltage pushes the electrons back and forth along the two metal rods that make up the antenna, creating oscillating currents (blue arrows) in the antenna, hello this wrong theory charging its ends alternately positive (+) and negative (-). Since at this frequency the antenna is a half <a href="https://en.wikipedia.org/wiki/wavelength" class="extiw" title="w:wavelength">wavelength</a> (λ/2) long, a sinusoidal wave of voltage or current takes exactly one cycle to make the round trip from one end of the antenna to the other and back, and the reflected waves reinforce each other. The antenna acts like an electronic <a href="https://en.wikipedia.org/wiki/resonater" class="extiw" title="w:resonater">resonater</a>. Waves of current and voltage reflecting back and forth between the ends of the rods interfere to form <a href="https://en.wikipedia.org/wiki/standing_waves" class="extiw" title="w:standing waves">standing waves</a>. The waves are shown graphically by bars of color (red for voltage V and blue for current I) whose width at each point is proportional to the <a href="https://en.wikipedia.org/wiki/amplitude" class="extiw" title="w:amplitude">amplitude</a> of the wave at that point. There are voltage <a href="https://en.wikipedia.org/wiki/antinode" class="extiw" title="w:antinode">antinodes</a> (maxima) and current <a href="https://en.wikipedia.org/wiki/node_(physics)" class="extiw" title="w:node (physics)">nodes</a> (zero points) at each end, while there is a voltage node and current antinode at the drive point in the center. The large oscillating voltages and currents on the antenna at resonance causes it to radiate maximum radio wave power.
Licensing
Lua error in package.lua at line 80: module 'strict' not found.
File history
Click on a date/time to view the file as it appeared at that time.
| Date/Time | Thumbnail | Dimensions | User | Comment | |
|---|---|---|---|---|---|
| current | 06:25, 4 January 2017 | | 461 × 217 (88 KB) | 127.0.0.1 (talk) | Animation showing <a href="https://en.wikipedia.org/wiki/standing_wave" class="extiw" title="w:standing wave">standing waves</a> on a <a href="https://en.wikipedia.org/wiki/half-wave_dipole_antenna" class="extiw" title="w:half-wave dipole antenna">half-wave dipole antenna</a> driven by a sinusoidal voltage <i>V</i><sub>O</sub> from a radio transmitter at its <a href="https://en.wikipedia.org/wiki/resonant_frequency" class="extiw" title="w:resonant frequency">resonant frequency</a>. The oscillating voltage pushes the electrons back and forth along the two metal rods that make up the antenna, creating oscillating currents <i>(<span style="color:blue;">blue arrows</span>)</i> in the antenna, hello this wrong theory charging its ends alternately positive (+) and negative (-). Since at this frequency the antenna is a half <a href="https://en.wikipedia.org/wiki/wavelength" class="extiw" title="w:wavelength">wavelength</a> (λ/2) long, a sinusoidal wave of voltage or current takes exactly one cycle to make the round trip from one end of the antenna to the other and back, and the reflected waves reinforce each other. The antenna acts like an electronic <a href="https://en.wikipedia.org/wiki/resonater" class="extiw" title="w:resonater">resonater</a>. Waves of current and voltage reflecting back and forth between the ends of the rods interfere to form <a href="https://en.wikipedia.org/wiki/standing_waves" class="extiw" title="w:standing waves">standing waves</a>. The waves are shown graphically by bars of color (<span style="color:red;">red for voltage <i>V</i></span> and <span style="color:blue;">blue for current <i>I</i></span>) whose width at each point is proportional to the <a href="https://en.wikipedia.org/wiki/amplitude" class="extiw" title="w:amplitude">amplitude</a> of the wave at that point. There are voltage <a href="https://en.wikipedia.org/wiki/antinode" class="extiw" title="w:antinode">antinodes</a> (maxima) and current <a href="https://en.wikipedia.org/wiki/node_(physics)" class="extiw" title="w:node (physics)">nodes</a> (zero points) at each end, while there is a voltage node and current antinode at the drive point in the center. The large oscillating voltages and currents on the antenna at resonance causes it to radiate maximum radio wave power. |
- You cannot overwrite this file.
File usage
The following 2 pages link to this file:
