Patent ID: 7397324

Claim:
A multilayer chip-type triplexer, comprising: an antenna input port; four matching transmission lines including first, second, third and fourth matching transmission lines for providing electrical or magnetic coupling through control of coupling coefficients of the transmission lines, each of the matching transmission lines having first and second terminals; and three band-pass filters at different frequencies including first, second and third band-pass filters each having an input port and an output port; wherein the input port of the first band-pass filter is electrically connected with the second terminal of the first matching transmission line, the input port of the second band-pass filter is electrically connected with the second terminal of the second matching transmission line, the input port of the third band-pass filter is electrically connected with the second terminal of the third matching transmission line, the first terminal of the third matching transmission line, the first terminal of the second matching transmission line, and the first terminal of the fourth matching transmission line are electrically connected together, and the first terminal of the first matching transmission line and the second terminal of the fourth matching transmission line are electrically connected with said antenna input port.