Telephonic communications – Supervisory or control line signaling
Patent
1997-01-23
1999-11-09
Isen, Forester W.
Telephonic communications
Supervisory or control line signaling
379283, 379386, H04M 150
Patent
active
059828749
ABSTRACT:
In a transmission system a pair of signalling tone signals is transmitted by a transmitter (2) to a receiver (6) via a transmission channel (4). In the terminal (6) a tone detector is used to detect the presence of the pair of signalling tone signals. In order to improve the reliability of the tone detector in the case of differing strength of both tone signals, the decision on the presence of the pair of signalling tone signals is based on a combined strength measure which is determined by an adder (23). The combined strength measure is compared with a reference level TH.sub.2. In a further embodiment, also a check on the level of the individual tone signals is done with comparators (11) and (9), in order to specify the maximum strength difference tolerated.
REFERENCES:
patent: 3882283 (1975-05-01), Proudfoot
patent: 4085295 (1978-04-01), Goto et al.
patent: 4395595 (1983-07-01), Nishitani et al.
patent: 4868872 (1989-09-01), Roberts et al.
patent: 5119322 (1992-06-01), Stroobach
patent: 5214693 (1993-05-01), Chujo
patent: 5619564 (1997-04-01), Canniff et al.
patent: 5649002 (1997-07-01), Brady et al.
patent: 5694466 (1997-12-01), Xie et al.
Isen Forester W.
Saint-Surin Jacques M.
Slobod Jack D.
U.S. Philips Corporation
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