Pulse or digital communications – Transceivers
Patent
1998-02-19
2000-07-11
Pham, Chi H.
Pulse or digital communications
Transceivers
375372, H04B 138, H04L 516
Patent
active
060883855
ABSTRACT:
A high speed modem is described that implements a scalable data rate ADSL link. The target data rate of the modem is scaled appropriately relative to a maximum available protocol rate by a factor M based on the signal processing capabilities available for performing DMT modulation and demodulation. An upstream transceiver is informed of the proposed scaling factor during a handshaking procedure, and thereafter the data rate of the channel is then scaled down by sending M copies of the same DMT symbol to the upstream transceiver, which effectively reduces the rate by such factor M. A self-executing calibration routine can be used for determining the appropriate scaling factor for such device, or alternatively, in some contexts a user can configure such scaling factor directly through a suitable interface. The invention can be implemented as a stand-alone unit with a self-contained DSP for performing necessary signal processing, or as a software modem located within a personal computer or similar computing device including portable digital devices such as cell phones, personal digital assistants, etc.
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Corrielus Jean B.
Integrated Telecom Express
Pham Chi H.
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