Fuzzy pattern comparator having automatic update threshold function

摘要

An apparatus and method for automatically updating a threshold in a fuzzy pattern comparator. A bit-field of an input data is simultaneously compared to simultaneously-input data patterns. An accumulated distance value is obtained for each data pattern, and the accumulated distance values are simultaneously compared with each other and a threshold to determine a minimum. The comparison is performed by a multipath feed-forward network which starts with the most significant bit and determines on a bit-by-bit basis and identifies which of the accumulated distance values and the threshold are a minimum. The threshold value is automatically updated to the minimum value during the comparison process if it is determined the threshold value is not a minimum. The automatic update threshold function is effective in pattern recognition systems which require periodic adaptation or adjustment in response to slowly changing pattern conditions.