Invalidity dossier
US 5594943
Method and apparatus for efficient handoffs by mobile communication entities
Current assignee: Cirrus Logic Inc
Added 9/23/2026, 6:35:23 PM
Active provider: DeepSeek · deepseek-flash
Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview — US 5,594,943 A
Title: Method and apparatus for efficient handoffs by mobile communication entities
Assignee / Inventor: Original assignee Pacific Communication Sciences Inc.; current assignee listed as Cirrus Logic Inc. Inventor: Kumar Balachandran.
Key dates: Priority date 1994-08-09; application (US 08/627,675) filed 1996-04-02; granted and published 1997-01-14; anticipated expiration 2014-08-09. Legal status: expired – lifetime.
Purpose: The invention concerns efficient handoffs between cells and/or sectors in a cellular mobile data communication network. In systems such as CDPD (Cellular Digital Packet Data) overlaid on AMPS (Advanced Mobile Phone Service), strict adherence to the CDPD specification does not permit CDPD coverage to closely emulate AMPS, because AMPS requires handoffs initiated by the base station while CDPD requires handoffs initiated by the mobile end system. A further problem is that scanning receivers used as the sole means for deciding channel changes are inefficient where the reverse channel is intermittent or bursty—a mobile end system may transmit too rarely to be monitored effectively, so it may not be identified as a handoff candidate in a reasonable time.
Plain-language scope: The patent text indicates that bit or symbol error rates of messages received by the mobile end system from the base station are assessed to determine when to cause the mobile end system to change channels to a channel assigned to another cell (execute a handoff). It notes that the point at which the mobile end system decides a handoff is to occur is therefore not dependent on its distance from a base station, since error rate is affected only after signal strength falls below a particular value. This can leave a cell defined for a digital packet data system substantially different in size from the desired host AMPS cell.
Not established by the excerpt: No claims are reproduced, so the precise claimed scope cannot be confirmed. The excerpt is incomplete (it cuts off mid-sentence referring to "Scotton"), and no figures, detailed description, or claim text are included.
Generated 10/1/2026, 9:42:40 PM
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PTAB challenges
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Assignment history
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Prior art
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Obviousness
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Extensions
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Derivative works
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