Antenna apparatus for use in mobile radio communication apparatus
CA 2293285 C · Owner: Yanagibashi, Hidehiro · Inventors: Yanagibashi, Hidehiro; Yamazaki, Masazumi; Egawa, Kiyoshi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
In a state that a whip antenna 101 is contained in a housing 110 of a cellular phone, a minute space dl is formed between a feeding spring 117 and an attaching member 112 conductive to a screw antenna base portion 120 so as to generate electrostatic capacitance which is, equivalent to the impedance characteristic of mono-pole antenna 114. Then, electrostatic capacitance and a coil portion of a screw antenna 113 constitute an LC series resonance circuit so as to improve the wide band of screw antenna 113.
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 April 26, 1999 and granted November 26, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 26, 2019.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 26, 2021.
- 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.