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:
Aug. 18, 1998
Filed:
Dec. 15, 1995
Karl Fredrik Gustafson, Stockholm, SE;
Jan-Erik Lundberg, Sollentuna, SE;
Telefonaktiebolaget LM Ericsson, Stockholm, SE;
Abstract
Methods and systems allowing for the following two Supervisory Audio Tone-Signalling Tone (SAT-ST) qualifications: (1) when detecting a ST as being on, the signalling tone signal is accepted if the SAT strength value indicates that the SAT is on, in accordance with the IS-54-B standard; and (2) when detecting the ST as being on and a momentary or instantaneous SAT strength value indicates that the SAT is off, the signalling tone signal is not accepted at this stage. However, should the instantaneous SAT strength subsequently be detected as being on while the signalling tone is still on, the signalling tone signal is accepted, which is a deviation from the IS-54-B standard. In one embodiment, the measurements of the ST duration are not started until SAT and ST both on.