DeepSense: Device-Free Human Activity Recognition via Autoencoder Long-Term Recurrent Convolutional Network

In the era of Internet of Things (IoT), human activity recognition is becoming the vital underpinning for a myriad of emerging applications in smart home and smart buildings. Existing activity recognition approaches require either the deployment of extra infrastructure or the cooperation of occupants to carry dedicated devices, which are expensive, intrusive and inconvenient for pervasive implementation. In this paper, we propose DeepSense, a device-free human activity recognition scheme that can automatically identify common activities via deep learning using only commodity WiFi-enabled IoT devices. We design a novel OpenWrt-based IoT platform to collect Channel State Information (CSI) measurements from commercial IoT devices. Moreover, an innovative deep learning framework, Autoencoder Long-term Recurrent Convolutional Network (AE-LRCN), is proposed. It consists of an autoencoder module, a convolutional neural network (CNN) module and a long short-term memory (LSTM) module, which aims to sanitize the noise in raw CSI data, extract high-level representative features and reveal the inherent temporal dependencies among data for accurate human activity recognition, respectively. All the hyperparameters in AE-LRCN are fine-tuned end-to-end automatically. Extensive experiments are conducted in typical indoor environments and the experimental results demonstrate that DeepSense outperforms existing methods and achieves a 97.6% activity recognition accuracy without human intervention.