| 摘要 |
The present invention relates to a band-rejection filter comprising:
- a filter input (1) and a filter output (2),
- a first signal transmission channel (3), called the direct channel, and a second signal transmission channel (4), called the secondary channel, located between said filter input and said filter output and coupled together at the filter input and the filter output, said direct channel and secondary channel each comprising at least one transmission line,
the secondary channel comprising a resonant element for which the resonance frequency is equal to a frequency to be rejected, called the first rejection frequency,
the direct channel and the secondary channel being designed to introduce at the rejection frequency a phase difference of 180° between the signal circulating via the direct channel and the signal circulating via the secondary channel,
the secondary channel (4) comprises in addition a filtering element (5) for which the cut-off frequency is different from said first rejection frequency in a way to create a second rejection frequency. |
