Resources Contact Us Home
Chase algorithm based differential decoder for soft decision Reed Solomon decoding in a QAM system

Image Number 5 for United States Patent #8149925.

A novel apparatus and method of differential decoding for use in a communication system such as a cable system. The differential decoding mechanism of the present invention enables the use of the Chase algorithm for Reed Solomon (RS) codes (i.e. non-binary codes). The mechanism is well suited for use in systems employing QAM data modulation/demodulation techniques and that also incorporate use of a differential encoder such as in DOCSIS capable cable modem systems. The differential decoding mechanism is operative to analyze the input to the differential decoder and adjust the decoding action accordingly. The mechanism generates the first and second candidate constellation points needed by the Chase algorithm. Considering the differential encoding, there are four possible constellation candidates. The differential decoder reduces these four possible options to two by eliminating from consideration two of them. Depending on the number of symbols to be improved by the Chase algorithm, this reduction can potentially reduce the number of options significantly.

  Recently Added Patents
Estimating optical characteristics of a camera component using sharpness sweep data
Helmet mandible
Method and apparatus for connecting to external device
System and method for detecting malicious code executed by virtual machine
Liquid low temperature injection molding process
Probe for ultrasound diagnostic apparatus
Memory controller including a hardware compression and decompression engine for managing system memory and graphical operations
  Randomly Featured Patents
Mixing faucet valve with diverter and stop check system
Radio frequency signal power amplifier combining network
Stethoscope having a body contact piece provided with two alternatively employed auscultation heads
Food topping device including a vibration device and adjustable discharge pan and screen assembly
Method for operating an isochronous cyclic communication system
System and method for a mass flow controller
Curing rim
Display control apparatus and method in a mobile terminal capable of outputting video data to an external display device
Image-forming apparatus having protrusion part for inhibiting flow of toner toward light-passing part
Method and device with durable contact on silicon carbide