CMDN: Continuous Human Activity Recognition Based on Multidomain Radar Data Fusion

Recently, human activity recognition (HAR) has gained significant attention as a research field, leading to the development of diverse technologies driven by its broad range of application scenarios. Radar technology has attracted much attention because of its unique advantages such as not being limited by environmental conditions such as light, shadow, and occlusion. In this article, a continuous HAR system based on multidomain radar data fusion (CMDN) is proposed. Firstly, in order to capture more detailed motion features of the human body, we apply the short-time fractional Fourier transform (STFrFT) to map radar data into the fractional domain, yielding a novel representation of human motion. Secondly, we develop an activity detector based on variable window length short-time average/long-time average (VW-STA/LTA) to accurately identify the start/end points of continuous human actions, addressing the challenge of difficult sequence segmentation in continuous activity recognition tasks. Finally, based on the multi-input multitask (MIMT) recognition network, the features of each domain are processed in parallel, and multiple input representations are fused to obtain the continuous activity classification results with high precision.