Patent ID: 9559659
Date: 2017-01-31
CPC Classifications: H03H

Claim:
1. A tunable filter comprising: a first resonator and a second resonator connected between a first port and a second port, the first resonator and the second resonator being configured to resonate at a reject band frequency, wherein the first resonator and the second resonator are configured to block signals within the reject band frequency between the first port and the second port, and wherein the first resonator and the second resonator are tunable to define the reject band frequency; and one or more coupling elements connected to both the first resonator and the second resonator and configured to define a pass band frequency that is different than the reject band frequency; wherein the one or more coupling elements are configured to adjust a frequency at which a simultaneous conjugate match of impedances of the first resonator and of the second resonator is substantially achieved to provide low insertion loss within the pass band frequency.