The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 13, 2001
Filed:
Sep. 09, 1997
Thomas Goerke, Middlesex, GB;
ICO Services LTD, London, GB;
Abstract
A mobile satellite communications system having at least one mobile terminal (,), at least one ground station (,), at least one relay satellite (,) interconnecting said user terminal (,) and said ground station (,), and a management store (,) associated with said ground station (,), in which the user terminal (,) is configured to initiate registration signalling with said store (,). The user terminal (,) initiates registration signalling when reception conditions relating to a downlink channel relayed via said satellite (,) become unsatisfactory over a given time greater than a predetermined minimum value and then return to a satisfactory condition. Specifically, signals received in a given channel are monitored in relation to predetermined criteria, and the duration of periods when the monitored signals do not meet the criteria are timed. Signals for updating the location of the user terminal registered in the management store, are transmitted when said monitored signals in said channel again meet said criteria, only if the timed duration for which the monitored signals do not meet the criteria, is not less than a predetermined time (T2).