Transceiver with rf loopback and downlink frequency scanning
CA 2253487 C · Owner: Zappala, Christopher F. · Inventors: Wen, Jack Chi-Chieh; Zappala, Christopher F.; Rucki, John Stanley
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A wireless base station has a transmitter and receiver. Transmission signals are applied to an antenna through a transmit bandpass filter that is tuned for a transmit band of frequencies. Received signals from the antenna are applied to the receiver through a receive bandpass filter that is tuned for a receive band of frequencies An RF switching array consisting of four RF switches interconnects the output of the transmitter and the input of the receiver such that normal loopback (self-test), and, scanning modes can be performed. In the normal mode the antenna is connected to the transmitter and receiver through the transmit and receive bandpass filters respectively. The transmit and …
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 November 9, 1998 and granted April 16, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 9, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 9, 2020.
- 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.