Band-pass filter for use in e.g. wireless LAN module, has signal branches forming resonator that propagates wave modes with amplitude equations, and wave resulting at output gate for locking frequencies and corresponding to equations

摘要

The filter has parallel connected signal branches (11, 12) that are connected to an input gate (IN) on input side and to an output gate (OUT) on output side. Two signal branches form a ring resonator that propagates two wave modes running in clockwise and anti-clockwise directions with two complex amplitude equations, respectively. Wave resulting at the output gate of the filter for two locking frequencies corresponds to the equations. The filter is suitable for integration in a low temperature cofired ceramic (LTCC) substrate.