Multiplex communications – Communication techniques for information carried in plural... – Adaptive
Reexamination Certificate
1998-11-13
2003-09-02
Kizou, Hassan (Department: 2662)
Multiplex communications
Communication techniques for information carried in plural...
Adaptive
C270S052160
Reexamination Certificate
active
06614801
ABSTRACT:
TECHNICAL FIELD OF THE INVENTION
The present invention relates generally to the field of telecommunications and, in particular, to circuits and methods for detecting the mode of a telecommunications signal.
BACKGROUND
Telecommunications systems connect users at geographically dispersed locations. The public switched telephone network (PSTN) evolved around providing a narrow-band medium for carrying voice traffic between users. More recently, the PSTN has been used to carry data to and from computers that connect to the PSTN with modems. These modems tropically carry data with bit rates of up to 56 Kbps.
The integrated services digital network (ISDN) was developed to carry higher bandwidth traffic over the existing local loop facilities of the PSTN. This network allows voice or data to be carried in digital form from user to user over the network. Various protocols or modes exist for transporting data over an ISDN network. Thus, the existing networks provide means for transporting telecommunications signals of a number of different modes between users. These modes are, essentially, incompatible and conventional equipment is typically dedicated to a specific telephone number such that a specific device only receives signals of a designated mode.
For the reasons stated above, and for other reasons stated below which will become apparent to those skilled in the art upon reading and understanding the present specification, there is a need in the art for circuits and methods for handling a variety of signal modes with a single number.
SUMMARY OF THE INVENTION
The above mentioned problems with telecommunications circuits and other problems are addressed by the present invention and will be understood by reading and studying the following specification. A system and method for detecting the mode of a telecommunications signal is described which contemporaneously evaluates the signal for compliance with at least two signal modes. This evaluation is accomplished by analyzing a bit stream of the telecommunications signal over a period of time, e.g., up to 2 seconds. In one embodiment, the mode is determined when a frame is successfully decoded from the bit stream according to one of the signal modes. Further, the method also keeps a score for each mode as the signal is evaluated to assist in determining the mode of the signal.
In particular, in one embodiment, a method for detecting the mode of a telecommunications signal is provided. The method receives the telecommunications signal and contemporaneously evaluates the telecommunications signal for compliance with at least two signal modes. When the evaluation indicates that the signal conforms to a first mode, the signal is processed as a first mode signal. When the evaluation indicates that the signal conforms to a second mode, the signal is processed as a second mode signal.
REFERENCES:
patent: 4667065 (1987-05-01), Bangerter
patent: 4672602 (1987-06-01), Hargrave et al.
patent: 5012470 (1991-04-01), Shobu et al.
patent: 5119412 (1992-06-01), Attallah
patent: 5267301 (1993-11-01), Nishii
patent: 5271058 (1993-12-01), Andrews et al.
patent: 5299260 (1994-03-01), Shaio
patent: 5361374 (1994-11-01), Sasaki et al.
patent: 5400327 (1995-03-01), Dezonno
patent: 5481605 (1996-01-01), Sakurai et al.
patent: 5526416 (1996-06-01), Dezonno et al.
patent: 5557668 (1996-09-01), Brady
patent: 5563937 (1996-10-01), Bruno et al.
patent: 5572585 (1996-11-01), Tsutsui
patent: 5572586 (1996-11-01), Ouchi
patent: 5581560 (1996-12-01), Shimada et al.
patent: 5633924 (1997-05-01), Kaish et al.
patent: 5675617 (1997-10-01), Quirk et al.
patent: 5684825 (1997-11-01), Ko
patent: 5706434 (1998-01-01), Kremen et al.
patent: 5974055 (1999-10-01), Imanishi
patent: 6130625 (2000-10-01), Harvey
patent: 6259706 (2001-07-01), Shimada
patent: 04373255 (1992-12-01), None
patent: 97/29563 (1997-08-01), None
English-language Abstract of JP 04 373255 A, published Dec. 25, 1992 (Ricoh Co. Ltd.), cited above.
Digi International Inc.
Kizou Hassan
Odland David
Schwegman Lundberg Woessner & Kluth P.A.
LandOfFree
Circuits and methods for detecting the mode of a... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Circuits and methods for detecting the mode of a..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Circuits and methods for detecting the mode of a... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3099354