The spread spectrum patent, 4,901,307, was issued on Feb. 13, 1990. Application date was October 17, 1986.
The power control patent, 5,056,109, was issued on October 8, 1991. Application date was Nov. 7, 1989.
The soft handoff patent, 5,101,501, was issued on March 31, 1992. Application date was Nov. 7, 1989.
The wave form patent, 5,103,459, was issued on April 7, 1992. Application date was June 25, 1990.
The rake receiver patent, 5,109,390, was issued on April 28, 1992. Application date was Nov. 7, 1989.
patft.uspto.gov
I don't know if the 17 year rule from date of issuance applies or if the 20 year from date of application rule controls. If the 17 year rule is applicable, the expiration date for the last of Q's basic patents is April 28, 2009. If the 20 year rule controls, the latest expiration date is June 25 , 2010.
There are many, many other patents which build on the basic ones, but I don't have the technical background to say without qualification that they are unassailable or otherwise impossible to avoid. Commentary from those in the know on this point is welcome. |
