Patent ID: 9577606
Date: 2017-02-21
CPC Classifications: H01Q,H03H

Claim:
1. A duplexer, comprising: an antenna terminal; a transmission amplifier terminal; a reception amplifier terminal; a transmission filter, wherein the transmission amplifier terminal is coupled to the antenna terminal via the transmission filter, wherein the transmission filter has a passband, and wherein the transmission filter comprises at least one resonator; a reception filter coupled to the reception amplifier terminal; a band-stop filter, wherein the reception filter is coupled to the antenna terminal via the band-stop filter, wherein the band-stop filter has a stop band in the passband of the transmission filter, and wherein the band-stop filter comprises at least one same resonator as the transmission filter; at least one matching circuit, wherein upon reception of a reception signal wherein upon transmission of a transmission signal wherein an isolation between the transmission amplifier terminal and the reception amplifier terminal in a transmission frequency band is 50 dB or better.