Multiplex communications – Duplex
Patent
1996-08-13
1999-11-23
Pham, Chi H.
Multiplex communications
Duplex
375222, H04L 514
Patent
active
059912782
ABSTRACT:
An asymmetric modem communications system achieves high speed data transfers through a telephone network that includes both digital and analog communications mediums. In general, the system includes means for concurrently communicating first and second signals, respectively, in opposite directions along the connection between the communications devices and modems for modulating the first and second signals with different modulation techniques. The communications occur in full duplex manner. In a possible implementation, a digital modem is interfaced to a digital network. The digital network is connected with a coder/decoder (codec). The codec is interfaced with a two-wire analog telephone connection, sometimes referred to as a copper loop. The telephone connection is interfaced with an analog modem. Both the digital and analog modems have a transmitter and a receiver. The digital modem has a transmitter that pulse modulates digital data and a receiver that receives and demodulates signals in accordance with the standard V.34 communications protocol (employs quadrature amplitude modulation/demodulation). The analog modem has a transmitter that transmits and modulates signals in accordance with the V.34 communications protocol and a receiver that demodulates the pulse levels into digital data. With the foregoing configuration, asymmetric data communications are realized. Specifically, the analog modem communicates to the digital modem using the V.34 communications protocol at a data rate of between 33,600 b/s and 2400 b/s, inclusive, while the digital modem communicates to the analog modem at a data rate of between 64,000 b/s and 2400 b/s, inclusive.
REFERENCES:
patent: 4597073 (1986-06-01), Staples
patent: 5103227 (1992-04-01), Betts
patent: 5329308 (1994-07-01), Binns et al.
patent: 5394437 (1995-02-01), Ayanogin et al.
patent: 5406583 (1995-04-01), Dagdeviren
patent: 5450530 (1995-09-01), Snyder et al.
patent: 5475711 (1995-12-01), Betts et al.
patent: 5550881 (1996-08-01), Sridhar et al.
patent: 5550908 (1996-08-01), Cai et al.
patent: 5631923 (1997-05-01), Kaku et al.
patent: 5663982 (1997-09-01), Hodge et al.
patent: 5671251 (1997-09-01), Blackwell et al.
patent: 5801695 (1998-09-01), Townshend
patent: 5809075 (1998-09-01), Townshend
Ngo Ricky Q.
Pham Chi H.
Telogy Networks Inc.
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