The first driver to respond to an event on the road brakes, the person behind, due to reaction time, brakes a fraction of a second later and has to brake a little harder to avoid hitting the person in front, the person behind them has to brake harder still, and somewhere down the backward wave
the traffic comes to a complete halt.
On the other hand, backward wave
seem to be more suppressed by input feed line.
Carlile examined both theoretically and experimentally the surface wave mode for the constant azimuthal variation (n = 1) and reported that this mode is a backward wave
The superposition of the forward and backward wave
localizes the SP by forming a standing wave pattern.
It shows that the normalized phase velocity of the novel helix SWS is lower than that of the conventional helix SWS, which shows that the novel structure has lower working voltage, and thus the risk of backward wave
oscillation may be reduced.
Barroso, "Retrieval approach for determination of forward and backward wave
impedances of bianisotropic metamaterials," Progress In Electromagnetics Research, Vol.
1,2) Such isolators must use absorbers to suppress the backward wave
propagation, even though they present a broad bandwidth.
Activities have included efforts at the Army's Harry Diamond Laboratories, working on backward wave
oscillators, traveling wave tubes and vircators; at the Naval Research Laboratory, with klystrons, gyrotrons, cyclotron autoresonance masers and free-electron lasers; and at the Air Force Weapons Laboratory on vircators and magnetically insulated transmission-line oscillators (MILO).
Arrows indicate forward wave and backward wave
inside each layer.
To suppress backward wave
oscillation and reflection oscillation, two concentrated attenuators made of Carburized porous beryllium oxide with relative permittivity and high loss tangent of 6.
When the chirality parameter is greater than the square root of the product of permittivity and permeability, the backward wave
will occur at one of the two circularly polarized eigenwaves [5,6].