Patent ID: 7190244
Filing Date: 2007-03-13
Classification: H01P

Abstract:
1. A passive network for operating at an operating frequency f comprising a capacitively loaded transmission line, the capacitively loaded transmission line including: a first uniplanar transmission line having a characteristic impedance Z a first microstrip conductor vertically offset from the first uniplanar transmission line, said first microstrip conductor electrically connected to the first uniplanar transmission line at one location at or near the first end and electromagnetically coupled to a first portion of the uniplanar transmission line at another location, wherein the first portion of the first uniplanar transmission line and the first microstrip conductor form a first microstrip shunt stub for capacitively loading the first uniplanar transmission line; one of a) a short circuit electrically connected to the second end for short-circuiting the second end, and b) a second microstrip conductor vertically offset from the first uniplanar transmission line, said second microstrip conductor electrically connected to the first uniplanar transmission line at one location at or near the second end and electromagnetically coupled to a second portion of the uniplanar transmission line at another location, wherein the second portion of the first uniplanar transmission line and the second microstrip conductor form a second microstrip shunt stub for capacitively loading the first uniplanar transmission line; and, wherein, at the operating frequency f, the capacitively loaded transmission line has a pre-determined characteristic impedance Z o that is less than Z 1 and an electrical length θ o that is larger than θ 1 .