Information terminal and information terminal system

Multiplex communications – Duplex – Duplex repeaters or extenders

Reexamination Certificate

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Details

C370S348000, C370S464000, C455S402000

Reexamination Certificate

active

07664060

ABSTRACT:
An information terminal incorporates a network interface and an extension interface, and in the case of outside call, an audio send signal is modulated into an audio signal frequency band, and sent to the exchange through a private telephone line and a subscriber's line by way of the network interface. An audio receive signal sent from the exchange through the subscriber's line and private telephone line is demodulated into an ordinary audio frequency band through the network interface. On the other hand, in the case of extension service, an audio send signal is converted into a packetized digital signal by an extension interface circuit, and is further modulated into a higher frequency band so as not to overlap with the audio signal frequency band, and is transmitted through the private telephone line.

REFERENCES:
patent: 4821265 (1989-04-01), Albal et al.
patent: 5231634 (1993-07-01), Giles et al.
patent: 5268666 (1993-12-01), Michel et al.
patent: 5717751 (1998-02-01), Yagi et al.
patent: 5742596 (1998-04-01), Baratz et al.
patent: 5831980 (1998-11-01), Varma et al.
patent: 6111570 (2000-08-01), Sugikawa et al.
patent: 6130893 (2000-10-01), Whittaker et al.
patent: 6404773 (2002-06-01), Williams et al.
patent: 6407987 (2002-06-01), Abraham
patent: 6434123 (2002-08-01), Park
patent: 6480510 (2002-11-01), Binder
patent: 6549906 (2003-04-01), Austin et al.
patent: 6580710 (2003-06-01), Bowen et al.
patent: 6668328 (2003-12-01), Bell
patent: 6731627 (2004-05-01), Gupta et al.
patent: 7054303 (2006-05-01), Miyazaki et al.
patent: 6-086362 (1994-03-01), None
patent: 07-193861 (1995-07-01), None
patent: 07-336432 (1995-12-01), None
patent: 11-075229 (1999-03-01), None

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