Abstract: Signal classification techniques for classifying signals occurring in a frequency band using a plurality of classifier procedures each dedicated to identify a particular signal or signal type. The classification procedures operate on spectrum activity data that may include pulse event data describing particular types of signal pulses occurring in the frequency band, power versus frequency data for sampling intervals of activity in a frequency band and/or raw analog-to-digital converter samples take of a received signal. The signal classification techniques are useful to identify wireless radio signals or other radio emissions occurring in an unlicensed radio frequency band. One type of classification procedure is a pulse timing template that is compared against accumulated signal pulse data to determine occurrence of a particular signal type.