Telephonic communications – Supervisory or control line signaling – Signal receiver
Reexamination Certificate
2004-03-08
2010-11-30
Matar, Ahmad F (Department: 2614)
Telephonic communications
Supervisory or control line signaling
Signal receiver
C379S283000, C379S377000
Reexamination Certificate
active
07844048
ABSTRACT:
In one embodiment, a tone event detector first determines whether the presence of a tone is indicated on the input signal, and then, based on this determination, selectively determines whether a tone has been detected on the input signal. For example, in one embodiment, tone detection is performed only when the presence of a tone is first indicated, such that if the presence of a tone is not indicated, tone detection need not be performed. This may help reduce complexity of a tone event detector since a simplified method may be used to indicate the presence of a tone, and the more complex algorithms for tone detection may be enabled only when needed. Also, in one embodiment, detection of a tone includes generating one or more tone characteristics corresponding to the detected tone which may then be used to determine whether the detected tone corresponds to a valid tone event.
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Aziz Ahsan U.
Pessoa Lucio F. C.
Su Wen Wu
Chiu Joanna G.
Freescale Semiconductor Inc.
Matar Ahmad F
Nguyen Khai N
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