05119397 is referenced by 163 patents and cites 17 patents.

A method and apparatus for directing mobile stations in a cellular mobile radio system to different sets of control channels, depending on whether the land system and the mobile stations have digital capabilities. The mobile stations operate to initially scan the same primary set of control channels and to read one of them, and to make a determination, based on the value of certain bits transmitted over the control channel and also the digital capabilities of the type of mobile station involved, whether to continue operation on the primary set of control channels, or whether to scan and read any secondary set of control channels. If a mobile station with digital capabilities decides to scan the secondary set of control channels, but does not find such channels, the mobile station determines that there are no secondary sets of control channels. In this case, if the mobile has analog capabilities, the mobile station will return to scanning the primary set of control channels.

Title
Combined analog and digital cellular telephone system having a secondary set of control channels
Application Number
7/514540
Publication Number
5119397
Application Date
April 26, 1990
Publication Date
June 2, 1992
Inventor
John R Bohaychuk
Richardson
TX, US
Jan E A S Dahlin
Jarfalla
SE
Agent
Burns Doane Swecker & Mathis
Assignee
Telefonaktiebolaget L M Ericsson
SE
IPC
H04Q 7/02
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