Transmission line impedance transformer - has one conductive zone joined to another by continuously varying width zone providing only one discontinuity

摘要

The transmission line impedance transformer in microstrip form comprises a first conductive zone (10) of constant width and predetermined impedance and a second conductive zone (11) connected to the first conductive zone. The second zone has a width which varies continuously from that of the first zone at a discontinuity plane (12) to a second selected width, the curvature being either convex or concave and the final width greater or small than that of the first zone. The presence of only one discontinuity avoids the reflective interferences normally obtained. Two or more identically shaped conductive or non-conductive zones (14a,14b) symmetrically about the first zone longitudinal axis are provided to conp compensate for inductive and capacitive effects at the discontinuity. The compensating zones may be e.g. rectangular or spade shaped and are capacitive in effect.