A Comparison of the Recursive and FFT-based Reassignment Methods in Micro-Doppler Analysis

Entropy-Based Concentration and Instantaneous Frequency of TFDs from Cohen’s, Affine, and Reassigned Classes

“…The reassignment is performed by mapping the computed data points from their initial coordinates closer to the true region of the signal support [ 14 , 38 ], also known as the centroid or center of gravity . The center of gravity is calculated for each windowed region of the t – f plane, and then the calculated energy values for that region are placed at that point, rather than at the geometric center [ 13 , 39 ].…”

The Use of the Reassignment Technique in the Time-Frequency Analysis Applied in VHF-Based Passive Forward Scattering Radar

“…However, despite the high potential of this method, it is still not very popular in the radar community. Namely, in the literature one can find results for the energy concentration in micro-Doppler signature analysis [40][41][42], characterization of frequency shift keying (FSK) signals [43], improving the quality of inverse synthetic aperture radar (ISAR) imaging [44] as well as in direction of arrival estimation [45] and Doppler radar tomography imaging [46]. The novelty presented in this paper is to apply the TF reassignment method and combine it with the Hough transform that aims to extract the Doppler rate of the target with the improved accuracy comparing the classical method existing in the literature.…”

“…Therefore, an additional simulation was performed 203 in which the geometry was appropriately modified by changing the transmitter position that aims 204 to reduce this fault. After these modifications the error was eliminated, and the results for both the The proposed method allowing signal concentration in the TF to be obtained improved the [40]. The increase in computational complexity in the concentrated 217 spectrogram technique results from the fact that 3 distributions are necessary to be implemented 218 in accordance to (20).…”

“…Therefore, the only difference results from the signal processing associated with the reassignment operation. For this reason, only the STFT and the reassigned STFT computational complexity are compared in Table 2 [40]. Table 2.…”