| 摘要 |
A transition 122 connects a ground backed coplanar waveguide (GCPW), which includes a hot conductor formed on a ground backed insulating substrate 120 and having parallel top ground planes 130, 131 on either side, to a ground backed microstrip transmission line 121 formed on an insulating substrate 120. The hot conductor of the GCPW and the hot conductor of the microstrip transmission line are electrically connected together, there being vias extending through the insulating substrate and forming an electrical connection between the top ground planes 130, 131 and the ground backing 205. The transition 122 from the GCPW structure to the microstrip structure is such that the characteristic impedance of the feed-line is a substantially constant 50 L along its length within the operating frequency range such that broadband operation is possible. In one aspect, the transition 122 is tapered in width and ends of the ground planes 130, 131 are rounded, and splay outwardly from the hot conductor. |
