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Title: Unsupervised training dataset curation for deep-neural-net RF signal classification
We consider the problem of unsupervised (blind) evaluation and assessment of the quality of data used for deep neural network (DNN) RF signal classification. When neural networks train on noisy or mislabeled data, they often (over-)fit to the noise measurements and faulty labels, which leads to significant performance degradation. Also, DNNs are vulnerable to adversarial attacks, which can considerably reduce their classification performance, with extremely small perturbations of their input. In this paper, we consider a new method based on L1-norm principal-component analysis (PCA) to improve the quality of labeled wireless data sets that are used for training a convolutional neural network (CNN), and a deep residual network (ResNet) for RF signal classification. Experiments with data generated for eleven classes of digital and analog modulated signals show that L1-norm tensor conformity curation of the data identifies and removes from the training data set inappropriate class instances that appear due to mislabeling and universal black-box adversarial attacks and drastically improves/restores the classification accuracy of the identified deep neural network architectures.  more » « less
Award ID(s):
2030234 2117822
Author(s) / Creator(s):
; ; ; ; ;
Markopoulos, Panos P.; Ouyang, Bing
Publisher / Repository:
SPIE Defense + Commercial Sensing
Date Published:
Medium: X
Orlando, Florida, United States
Sponsoring Org:
National Science Foundation
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