Image Number 2 for United States Patent #6538585.
The present invention pertains to a distance-enhancing coding method that can be applied to digital recording and digital communications. It improves the time-varying maximum transition run method used in a conventional distance-enhancing coding to avoid main error events .+-.(1,-1) from happening. Under the premise of maintaining a code gain of 1.8 dB, the code rate can be increased from 3/4 to 4/5. The invention also provides a method of using an enumeration algorithm and an exhaustive method to search for block codes for distance-enhancing coding, which can find required codes by following specific steps.