Abstract: An algorithm for pattern recognition and the calculation of the threshold valuehas deen proposed to speed up the pattern matching of certain waveforms.The main idea is that from the expected amplitude and the vertical and horizontal fluctuation of the waveform a characteristic vector is derived and the thres hold value calculated.For certain a set of wave forms the matching operation is carried outonly for those waveforms that have the same vector as the pattern,and are within thethreshold value.For some wavefoms,the information compression ratio reaches 90～98%,the speed of the computation is increased by a factor of 10—30.