2004 Volume 40 Issue 11 Pages 1114-1123
This paper presents a new method for the signal separation of interleaved pulse trains consisting of several pulse trains emitted from independent signal sources, some of which possibly exist for only a short period of time. The separation is based on the differences in the pulse repetition intervals (PRIs) of the signal sources. To detect each pulse train, we derive a map from the input signal to a function of two variables: time and PRI, which we call the PRI map. By taking the absolute value of the PRI map, we obtain a short-time PRI spectrum, from which we can use thresholding to estimate the number of signal sources, their time duration, and the PRIs. The PRI map is an extension of the PRI transform, which was proposed by the author previously. The extension is based on the time-period analysis. The construction of the PRI map is similar to that of a wavelet transform. The difference is that the PRI map is a nonlinear transform, while the wavelet transform is a linear one. Simulation results are presented on the performance of the signal separation of interleaved pulse trains using the PRI map. Finally, the performance analysis is given to show the detection ability of the PRI map for short pulse trains.