Methods and apparatus for the efficient implementation of signal

Television – Miscellaneous

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

348716, 714775, H04N 726

Patent

active

059561025

ABSTRACT:
Methods and apparatus for performing packet synchronization recovery and error detection operation on packets including a CRC check byte, e.g., MCNS packets, are described. The present invention uses a memory during a sync acquisition mode of operation to serve as a storage device for the output of a first function circuit. The delayed bits are used as the input along with current bits from the packet stream to a second function circuit. The second function circuit generates a syndrome byte of interest. When the received packets are error free and the decoder is properly aligned with the packet structure of the bitstream, the syndrome byte of interest will assume a preselected value, e.g., 47 Hex. Once packet synchronization has been achieved, the relatively few bits output by the first function circuit which are required as delayed inputs to the second function circuit are identified and stored using a delay register which is much smaller than the memory. By switching to the delay register, the memory previously used for feedback purposes is rendered available for use during sync lock mode for other purposes. Thus, the memory can be re-used as a packet data delay memory during sync lock mode operation. In such an embodiment, received packet data is delayed one packet time period so that the generated syndrome byte corresponding to the delayed packet data can be inserted into the packet stream as the first byte of a transport data packet thereby providing an error indicator signal at the start of a packet.

REFERENCES:
patent: 4059825 (1977-11-01), Greene
patent: 5703887 (1997-12-01), Heegard
International Standards Organization--Moving Picture Experts Group, Recommendation H. 222.0, ISO/IEC 13818-1 "Information Technology--Generic Coding of Moving Pictures and Associated Audio: Systems" pp.i-viii; 1-155. (Nov. 13, 1994).
International Standards Organization--Moving Picture Experts Group, Recommendation H. 262, ISO/IEC 13818-2 "Information Technology -Generic Coding of Moving Pictures and Associated Audio Information: Video" pp.i-viii; 1-155. (Nov. 9, 1994).
International Telecommunication Union, ITU-T "Digital MultiProgramme Systems for Television Sound and Data Services for Cable Distribution" Recommendation J.83; pp. 1-5; annex A-D. (Oct. 1995).
SCTE Digital Video Subcommittee "Digital Video Transmission Standard for Cable Television" DVS031 Rev.1, pp. 1-17. (Mar. 27, 1997).
MCNS "Data-Over-Cable Interface Specifications, Radio Frequency Specification", Document No. SP-RFII01-970326, Interim Specification, pp. i -xiv, 1-174. (1997).

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Methods and apparatus for the efficient implementation of signal does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Methods and apparatus for the efficient implementation of signal, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Methods and apparatus for the efficient implementation of signal will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-85311

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.