Filter
CA 2116366 A1 · Owner: Lk-Products Oy · Inventors: Jantunen, Heli; Turunen, Aimo
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A transmission line filter comprises four resonators (100,200,300,400),and transmission zeroes can be added to the transfer function of the filter using a known phasing coupling technique using a transmission line (53,54) coupled between two resonators. The location of the transmission zeroes can be varied using control circuits (A,B). Each control circuit comprises a series coupled inductance (55,58) and capacitance (56,59) forming a resonance circuit,the resonance frequency of which can be varied using a variable d.c. voltage (V1 ,V2 ). The inductance of each control circuit is arranged adjacent its respective transmission line so that the two are weakly electromagnetically coupled. By …
Read the whole patent
Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed February 24, 1994. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended February 24, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 24, 2016.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.