Patent ID: 9564871
Date: 2017-02-07
CPC Classifications: H01P,H03H,H04B

Claim:
1. A Radio Frequency (RF) filter comprising: a coupler configured to receive an input signal through a first port of the coupler, to divide the input signal, to output the divided signals through second and third ports of the coupler, to combine signals received through the second and third ports of the coupler according to phases of the signals, and to output the combined signal through the first port of the coupler or as an output signal of the RF filter through a fourth port of the coupler; a first filter unit having a first port of the first filter unit connected to the second port of the coupler and a second port of the first filter unit connected to the third port of the coupler, for having a predetermined frequency filtering characteristic; and first and second switch units having the coupler and the first filter unit disposed therebetween for dynamically establishing a signal path according to an external switching control signal so that input and output ports of the RF filter are connected to the first filter unit directly or indirectly via the coupler, wherein a signal passes through the coupler, or a signal passes through the filter or a signal bypasses the first filter unit and the coupler.