| 摘要 |
<p>A length of strip transmission line uses two symmetrically spaced center conductors (22,24) between two groundplanes (28,30). These conductive strips produce an even-mode electric field between the two groundplanes (28,30) when excited in-phase and an odd-mode electric field when excited in anti-phase relationship. For the latter case, the phase velocity of the odd-mode is significantly affected by the electric field in the gap region (S) between the conducting strips. By varying the relative dielectric constant of a material (26) located in the gap region (S), e.g., by means of a voltage-controllable dielectric (26) such as barium-titanate compositions, the phase velocity and, hence, the phase shift of an RF signal propagating through the strip transmission medium can be controlled. <IMAGE></p> |
