Abnormal Communication Signals Recognition Based on Image Enhancement and Improved Memory-Augmented Autoencoder

Figure 4

Time-frequency spectrograms of six abnormal signals.

(a) BPSK signals with the comb spectrum jamming

(b) BPSK signals with the multitone jamming

(c) Pulse jamming on BPSK signals

(d) BPSK signals with the single-tone jamming

(e) Linear frequency sweeping jamming on BPSK signals

(f) BPSK signals with the noise FM jamming