Low pass filter

摘要

A low pass filter includes a signal transmission line, a first open stub, a second open stub, a first coupling line, and a second coupling line. The signal transmission line is connected between a first port and a second port, and operable to transmit RF signals from the first port to the second port. The signal transmission line defines a first side and a second side opposite to the first side. The first open stub and the second stub are disposed on the first side and perpendicularly connected to the signal transmission line. The second open stub and the first open stub co-define a T-shaped gap. The first coupling line is parallel to the signal transmission line and disposed in the T-shaped gap. The second coupling line is parallel to the signal transmission line and disposed on the second side of the signal transmission line.

主权项

1. A low pass filter, comprising:
a first port; a second port; a substantially linear strip shaped signal transmission line connected between the first port and the second port, and operable to transmit radio frequency signals from the first port to the second port, the signal transmission line defining a first side and a second side opposite to the first side; a first open stub disposed on the first side of the signal transmission line and perpendicularly connected to a part of the signal transmission line adjacent to the first port; a second open stub disposed on the first side of the signal transmission line and perpendicularly connected to another part of the signal transmission line adjacent to the second port, the second open stub and the first open stub co-defining a T-shaped gap; a first coupling line parallel to the signal transmission line and disposed in the T-shaped gap, the first coupling line defining a first via; and a second coupling line parallel to the signal transmission line and disposed on the second side of the signal transmission line, the second coupling line defining a second via.