Ultra-Low Power Human Proximity Sensor Using Electrostatic Induction

Survey of Decentralized Solutions with Mobile Devices for User Location Tracking, Proximity Detection, and Contact Tracing in the COVID-19 Era

“…• Improved signal processing at the transmitter side, for example, by the optimized power amplifier to obtain high efficiency at low transmit power levels [166]; • Improved signal processing at the receiver side-the authors of [31] used, for example, dynamic modeling via Markov chains for more efficient integration of sensors readings for positioning; • Improved communications and/or localization protocols for example by optimized routing of the events or packets [167]; • Ultra low-power communication technologies: low-power technologies, such as BLE, ZigBee, LoRa, etc., are essential for a lasting battery life, but decreasing even more the power consumption is a topic of active research under the umbrella of "ultra low-power" technologies such as wireless-powered networks with back-scattered communications [168], tunable impulse radio UWB technologies [169], or wearable technologies relying on sensors which use the electrostatic induction current generated by human motion [170]; • Data compression methods for transmitting a lower amount of data by removing redundancies in data to be transmitted -while such methods have been vastly studied in the context of wireless communications, e.g., in [171] or via compressed sensing in [85], their applicability to user tracking and contact tracing is still to be determined; • Approximate computing methods rely on trading accuracy for a lower power consumption [172], for example, by reducing the number of quantization bits of by approximating some tasks in the execution flow; • Task offloading methods [173] rely on delegating/moving some of the more computationally demanding tasks to an edge or cloud server; such methods typically demand the presence of a centralized unit/server and therefore are not well suited to decentralized approaches. In addition, task offloading increases the wireless transmission delays and may hinder a real-time contact-tracing app's viability.…”

Ultra-Low Power Hand Gesture Sensor Using Electrostatic Induction

“…Figure 1 shows an overview of the proposed sensor. The proposed gesture sensor is based on an ESI-based motion sensor [8,9]. The electrode consists of a metal sheet and an electret foil, as illustrated in Figure 2.…”

“…By observing the ESI current, hand movements can be detected. In conventional works [8,9], a single electrode was used to detect hand motion. In contrast, two electrodes are utilized in this study, as shown in Figure 2, to recognize hand gestures, such as hand movement from right to left and left to right.…”

“…In contrast, two electrodes are utilized in this study, as shown in Figure 2, to recognize hand gestures, such as hand movement from right to left and left to right. The ESI currents generated in the electrodes are significantly small, less than 1 nA [9]. To process such a small current with low power, a sensor front-end circuit, such as an amplifier, comparator, and phase comparator is newly designed in this study, as shown in Figure 1.…”

“…This system consists of sensing electrode using an electret (Figure 2) and a gesture recognition chip, which is first designed in this study to achieve ultra-low power gesture sensing. As explained above, the proposed sensor is based on the ESI-based motion detection mechanism proposed in conventional works [8,9]. The circuit proposed in this paper is improved compared to that in [8,9].…”