WiDMove - um sensor de movimento direcional baseado em perturbações do sinal eletromagnético de interfaces 802.11
ResumoThe accurate detection of people in indoor environments requires high-cost devices, while low-cost devices, in addition to low accuracy, offers little information about the monitored events. The perturbations that can affect the electromagnetic signals used by 802.11 interfaces make this type of device a low-cost sensor, widely available, and enoughly accurate for several applications. In this work, we propose the WiDMove, a proposal to detect the entry and exit of people indoors using channel quality measurements (known as Channel State Information - CSI) offered by the IEEE 802.11n standard. Our proposal is based on signal processing and machine learning techniques, which allow us to extract and classify event signatures using the CSI. In lab tests with off-the-shelf 802.11 interfaces, we collected CSI samples that were affected by 8 different people. From this collected data we extracted the signature of the entry and exit events using some techniques such as Principal Component Analysis (PCA) and Short-Time Fourier Transform (STFT). We trained a Support Vector Machine (SVM) classifier and validated it with cross-validation, using the K-Fold and Leave-One-Out techniques. WiDMove presented that can reach an average accuracy above 85%.
SILVA, Bruno Soares da; LAUREANO, Gustavo Teodoro; CARDOSO, Kleber Vieira. WiDMove - um sensor de movimento direcional baseado em perturbações do sinal eletromagnético de interfaces 802.11. In: SIMPÓSIO BRASILEIRO DE REDES DE COMPUTADORES E SISTEMAS DISTRIBUÍDOS (SBRC) , 2018 Anais do XXXVI Simpósio Brasileiro de Redes de Computadores e Sistemas Distribuídos. Porto Alegre: Sociedade Brasileira de Computação, may 2018 . ISSN 2177-9384.