Patent · US Expired

Dual mode QAM/VSB receiver

US6842495B1 · kind B1 · utility

51Cited by
44References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 3, 1999
Grant dateJan 11, 2005
Priority date
Expiry dateNov 3, 2019

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N11/24
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A television receiver system capable of receiving and demodulating television signal information content that has been modulated and transmitted in accordance with a variety of modulation formats is disclosed. In particular, the system is able to accommodate receipt and demodulation of at least 8 and 16-VSB modulated signals in order to support US HDTV applications, as well as 64 and 256-QAM modulated signals, for European and potential US CATV implementations. The system includes carrier and timing recovery loops adapted to operate on an enhanced pilot signal as well as decision directed carrier phase recovery loops. Phase detectors operate on I and Q rail signals, or generate a Q rail from a Hilbert transform of the I rail. Decision directed loops incorporate a trellis decoder in order to operate on sequence estimated decisions for improved reliability in poor SNR environments.

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