Patent · US Expired

Method and apparatus for encoding compressible data for transmission over variable quality communication channel

US7339881B1 · kind B1 · utility

5Cited by
7References
22Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 12, 2003
Grant dateMar 4, 2008
Priority date
Expiry dateDec 19, 2025

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L5/0044
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

A multi-carrier communication system (400) groups subchannels (802) into different quality-of-signal (QoS) regions (804). An unconstrained optimization process (1200) is performed independently for the subchannels (802) of the different QoS regions (804) to allocate bit rates and power to the individual subchannels (802) so that the indicated QoS will result. Coders (504, 508, 512, 516, 1700) partition and error-correction encode source information using encoding schemes matched to the different QoS regions (804). A set (1100) of only a few directed QoS partition vectors (1102) direct the unconstrained optimization process (1200) to attempt bit-rate and power allocations on only a few promising groupings of subchannels (802) and QoS regions (804). An iterative process may take place between bit-rate and power allocation on one side and source information coding on the other for different directed QoS partition vectors (1102) to identify the best solution. A coder (1700) may use a dual allocation process (1800) to iteratively combine a rate-allocation process (1724) with a QoS-region-allocation process (1726) to specify codebooks (1720) for use by a codebook quantizer (1718).

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.