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I've been reading a lot about traveling and standing waves, and I am right now reading about traveling wave antennas, to my understanding ALL antennas should be traveling wave antennas, but this is not the case of what i read online, and there is also not too much information about it.

For instance, the Wikipedia article states that the most common type of traveling wave antenna are the beverage and rhombic antenna.

I can't find much information about this, care to explain to me why? Is it because the propagation pattern of the wave has to meet some standards in order to be in the traveling wave category? Or are all antennas(like the ones in the microwave dishes and all others used in transmission and reception) really traveling wave antennas as i believe? and so are all waves(talking about radio waves in this case) that propagate traveling waves? Does modulation play any role here?

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A standing wave occurs when two signals that have the same frequency are traveling in opposite directions through a medium simultaneously.

Most antennas, such as the simple dipole, have impedance discontinuities at their ends that cause energy to be reflected back down the conductor, creating the conditions required for standing waves.

On the other hand, traveling wave antennas such as the Beverage or rhombic are deliberately terminated at their end(s) by a resistance that matches the characteristic impedance of the conductor. This eliminates the energy reflection and the backward-traveling wave, leaving only the forward-traveling wave — and no standing wave.

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  • \$\begingroup\$ Hi, and thank you really much for your explanation, now i understand. But this makes me rise new questions. Before, in my mind, i thought all the antennas were traveling wave type because that's what they radiate, right? The radiation of all antennas is a traveling wave, since they radiate waves that travel through space. Am i right with this assumption? Is the radiation on a traveling wave antenna the same as on the standing wave antenna? I didn't know that what makes a traveling wave antenna is the way the wave propagates on the wire itself. Thank you again! \$\endgroup\$ – Rich Mar 21 '15 at 22:40
  • \$\begingroup\$ Yes, all antennas couple energy to the environment, and that energy travels away from the antenna as an electromagnetic wave. But that isn't how antenna designs are classified. \$\endgroup\$ – Dave Tweed Mar 21 '15 at 22:46
  • \$\begingroup\$ Alright, thank you! One last question, are both of them, used for the same purposes? Or are there uses that one would work better at than the other would? If we're explicitly talking about them being travelingwave and standingwave \$\endgroup\$ – Rich Mar 21 '15 at 23:50
  • \$\begingroup\$ Well, I'm not really an authority on the usage of the antennas, but I seem to recall that the Beverage antenna is most often used for receiving, especially at long wavelengths, because it is the most cost-effective directional antenna at those wavelengths. Rhombic antennas are used by space-constrained hams on the HF bands, because they're more compact and easier to construct than other designs. \$\endgroup\$ – Dave Tweed Mar 21 '15 at 23:57
  • \$\begingroup\$ oh alright, but that's beacuse of the antenna itself, so assume that being travelingwaveantenna or standingwaveantenna has no impact whatsoever. Thank you for your help mate, really appreciated it! You've teached me a lot. \$\endgroup\$ – Rich Mar 22 '15 at 3:19

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