Integrated filter construction
AssigneeLK-Products Oy
InventorsSeppo Yrjola, Kimmo Koskiniemi
Life of this patent
Estimating the term…
Abstract
A harmonic filter is added to a radio frequency filter comprising at least one transmission line resonator (R1; R2; R3) to filter harmonic multiples of the filter's operating frequency. Coupling to the harmonic filter occurs through matching couplings and transmission lines (7; L1 to L9; L20; L28) in the filter or via the electromagnetic field of said transmission line resonator (R1; R2; R3). The harmonic filter advantageously comprises striplines (L13 to L19; L21 to L27; L29 to L49) manufactured in conjunction with the other stripline structures in the filter.
Claims10
An integrated radio frequency filter and harmonic filter comprising:
- an input port,
- an output port,
- at least one transmission line resonator having a certain operating frequency band, and
- a coupling circuit disposed between said input port and said output port to couple radio frequency power between said input port and said output port and said transmission line resonators,
- the integrated radio frequency filter and harmonic filter further comprising:
- an attenuating circuit disposed between said input port and said output port to attenuate frequency components of particular frequency bands outside said operating frequency band and comprising strip conductors having electrical lengths which are predetermined fractions of a wavelength of a harmonic of said operating frequency band,
- said coupling circuit and said attenuating circuit having at least one common element.
The radio frequency filter of any one of the preceding claims, wherein said coupling circuit comprises matching couplings,
- said strip conductors being in galvanic contact with said matching couplings.
Dependencies are inferred from the claim text.