RespTracker: Multi-user Room-scale Respiration Tracking with Commercial Acoustic Devices

Ubiquitous WiFi and Acoustic Sensing: Principles, Technologies, and Applications

“…[5] Phasebeat [7] RT-Fall [10] Liu  . [6] FarSense [32] MoBreath [51] WiPhone [50] SiFall [15] FILA [67] FIMD [66] Widar [57] mD-Track [59] Widar2.0 [58] DAFI [62] WiDE [68] Fidora [69] WiKey [18] WiFi-ID [54] WiWho [53] FingerPass [72] Nicolaou and Efstratiou [78] Amaging [87] SpiroSmart [88] SpiroSonic [90] Resptracker [91] BatMapper [94] Pradhan   [95] CARACAL [96] Dong  . [97] Kafle  .…”

“…Health-related applications based on acoustic mainly rely on the detection of physiological conditions, such as the capture of human breathing, heartbeat, and so on, or some event monitoring, such as the fall detection, abnormal sleep behaviors, and so on, as well as medical-related assistance control to assist body recovery, etc. Larson et al [88][89][90][91]142] captured physiological signals, such as human respiration, heartbeat, vital capacity, chest wall motion, and some other non-voice sounds, such as swallowing during eating. Based on these physiological signals, Nahdakumar et al [142] turned a cell phone into an active sonar system that emits modulated sound signals and detects breathing-induced minute movements of the chest and abdomen from reflexes, and developed the identification of various types of sleeps from sonar reflexes algorithms for apnea events, including obstructive apneas, central apneas, and hypopneas.…”

“…SpiroSmart [88] uses a built-in microphone for spirometry. SpiroSonic [90] measures the human chest wall motion through acoustic sensing and interprets it as an index of the lung function based on clinically validated correlations.…”

“…After obtaining the WiFi or acoustic signal, the next step is to characterize it using various sensing techniques. Similar to WiFi sensing, typical applications based on acoustic sensing include daily actions monitoring [73][74][75][76][77][78] , gesture and hand movements recognition [79][80][81][82][83][84][85][86][87] , health caring [88][89][90][91][92] , localization and navigation [93][94][95][96][97][98] and privacy and security [99][100][101][102][103][104][105][106][107][108][109][110][111] . In the following, we will also introduce the basic content of signals and other characterization methods.…”

ExpresSense: Exploring a Standalone Smartphone to Sense Engagement of Users from Facial Expressions Using Acoustic Sensing

“…In this section, we discuss how acoustic sensing has been used in various applications and how they have inspired the idea of ExpresSense. Acoustic signals have been used extensively in coarse-grained motion and location tracking of objects [7,13,28], as well as tracking subtle movements like respiratory patterns of individuals [17,45]. In EchoSpot [31], target localization is performed using Frequency Modulated Continuous Wave (FMCW) signals that get reflected in the microphone from different paths.…”