Research Article

Semi-supervised Learning for Automatic Modulation Recognition Using Haar Time–Frequency Mask and Positional–Spatial Attention

Figure 11

Test sample points of two supervised methods and HTF-PSA-SSL after dimensionality reduction using t-SNE under 0 dB signals. (a) Supervised (100%) and (b) HTF-PSA-SSL are well-aggregated. (c) Supervised (1%) is heavily scattered.
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