Spectral Cross-Domain Neural Network with Soft-adaptive Threshold Spectral Enhancement

TL;DR

This paper introduces SCDNN, a novel deep learning model that integrates spectral and time domain information for ECG classification, using a soft-adaptive threshold spectral enhancement mechanism to improve accuracy and efficiency.

Contribution

The paper presents a new neural network architecture with a soft-adaptive threshold spectral enhancement block that enables simultaneous spectral and temporal domain learning in ECG classification.

Findings

SCDNN outperforms state-of-the-art methods on PTB-XL and MIT-BIH datasets.

The model achieves high accuracy with low computational cost.

The convergence of trainable spectral thresholds is numerically validated.

Abstract

Electrocardiography (ECG) signals can be considered as multi-variable time-series. The state-of-the-art ECG data classification approaches, based on either feature engineering or deep learning techniques, treat separately spectral and time domains in machine learning systems. No spectral-time domain communication mechanism inside the classifier model can be found in current approaches, leading to difficulties in identifying complex ECG forms. In this paper, we proposed a novel deep learning model named Spectral Cross-domain neural network (SCDNN) with a new block called Soft-adaptive threshold spectral enhancement (SATSE), to simultaneously reveal the key information embedded in spectral and time domains inside the neural network. More precisely, the domain-cross information is captured by a general Convolutional neural network (CNN) backbone, and different information sources are merged by a self-adaptive mechanism to mine the connection between time and spectral domains. In SATSE, the knowledge from time and spectral domains is extracted via the Fast Fourier Transformation (FFT) with soft trainable thresholds in modified Sigmoid functions. The proposed SCDNN is tested with several classification tasks implemented on the public ECG databases \textit{PTB-XL} and \textit{MIT-BIH}. SCDNN outperforms the state-of-the-art approaches with a low computational cost regarding a variety of metrics in all classification tasks on both databases, by finding appropriate domains from the infinite spectral mapping. The convergence of the trainable thresholds in the spectral domain is also numerically investigated in this paper. The robust performance of SCDNN provides a new perspective to exploit knowledge across deep learning models from time and spectral domains. The repository can be found: https://github.com/DL-WG/SCDNN-TS