An RF/IF signature trigger for acquiring received RF signal data is generated by correlating the received RF signal data in the form of a time domain RF/IF signal, a detected RF/IF signal and/or a frequency domain RF/IF signal with a reference signal defined by a signal signature record representing desired/undesired RF/IF signal patterns, detected RF pulse shapes, special RF markers used specifically for triggering signal acquisitions, particular signal patterns of interest and the like. The resulting correlation factor continuously calculated in real time is compared with a variable correlation threshold such that when the correlation factor reaches the variable correlation threshold, either positive or negative, the RF/IF signature trigger is generated to acquire the received RF signal data for analysis.