Abstract: Recognizing a signal begins by receiving the signal and sampling it at a plurality of sampling points to produce a plurality of signal values. A statistical moment of the signal is calculated using the signal values according to the formula: ##EQU1## where: N=the number of sampling points;n=1<n<NX=the signal value of the signal at the sampling point;.mu.=a mean of the signal values;.sigma.=a standard deviation of the signal values; andk=an integer greater than 1.The calculated statistical moment is then compared with a plurality of stored signal identifications and the received signal is recognized as similar to one of the stored signal identifications. Preferably, the calculated statistical moment is used to create a feature vector which is quantized, and a weighted sum of the quantized feature vector is used to access a memory which stores the signal identifications.
Type:
Grant
Filed:
May 2, 1990
Date of Patent:
May 11, 1993
Assignee:
Broadcast Data Systems Limited Partnership
Abstract: Method and apparatus for classifying broadcast information first receives the broadcast information and processes it to provide a plurality of a low bandwidth analyzed waveforms. The analyzed waveforms are used to generate a spectragram which is then compared with a plurality of reference spectragrams stored in a first stage reference library. The first stage reference spectragrams are then queued in order of their similarity to the generated spectragram. Next, a plurality of second stage reference patterns, which correspond to the first stage reference spectragrams, are correlated with one of the analyzed waveforms in the queueing order established previously. A correlation value is provided for each second stage reference pattern stored in the second stage reference library.
Type:
Grant
Filed:
June 24, 1987
Date of Patent:
June 27, 1989
Assignee:
Broadcast Data Systems Limited Partnership
Inventors:
Stephen C. Kenyon, Laura J. Simkins, Richard L. Sebastian