04438511 is referenced by 206 patents and cites 3 patents.

A high speed digital data modem particularly suited for use on a dial up telephone line is disclosed. For the transmit ensemble, the telephone passband is divided into sixty-four sub-bands each with a carrier located approximately in the center of each sub-band. Each carrier is amplitude and phase modulated in order to encode five (5) bits. One carrier is used as a reference signal for phase and amplitude. The modulated carriers can be changed in data content every epoch. By use of packetization of data, individual amplitude correction, and individual phase correction for each carrier, the high speed modem may achieve up to 12000 bps over a dial up line with a simultaneous 300 bps reverse channel.

Title
Packetized ensemble modem
Application Number
6/205744
Publication Number
4438511
Application Date
November 10, 1980
Publication Date
March 20, 1984
Inventor
Paul Baran
Menlo Park
CA, US
Agent
Townsend and Townsend
Assignee
Telebit Corporation
CA, US
IPC
H04J 4/00
H04J 11/00
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