Patent ID: 7885613
Filing Date: 2011-02-08
Classification: H04B

Abstract:
1. A multiband high-frequency circuit used between an antenna capable of conducting transmission and reception in at least three communications systems, and transmitting and receiving circuits of at least three communications systems, comprising a first high-frequency switch circuit for switching the connections of said antenna to first and second paths, a first diplexer circuit disposed in said first path, and a second diplexer circuit disposed in said second path; each of said first and second diplexer circuits comprising a lower-frequency-side filter circuit and a higher-frequency-side filter circuit; a path connected to the lower-frequency-side filter circuit of said first diplexer circuit being provided with a bandpass filter circuit, and a second high-frequency switch circuit disposed downstream of said bandpass filter circuit for switching the two-way connection of said bandpass filter circuit to a receiving circuit of the first communications system and a transmitting/receiving circuit of the third communications system; a path connected to the higher-frequency-side filter circuit of said first diplexer circuit being connected to a receiving circuit of the second communications system; a path connected to the lower-frequency-side filter circuit of said second diplexer circuit being connected to a transmitting circuit of the first communications system; and a path connected to the higher-frequency-side filter circuit of said second diplexer circuit being connected to a transmitting circuit of the second communications system.