Augmenting everyday surfaces with interaction sensing capability that is maintenance-free, low-cost (about $1), and in an appropriate form factor is a challenge with current technologies. MARS (Multi-channel Ambiently-powered Realtime Sensing) enables battery-free sensing and wireless communication of touch, swipe, and speech interactions by combining a nanowatt programmable oscillator with frequency-shifted analog backscatter communication. A zero-threshold voltage field-effect transistor (FET) is used to create an oscillator with a low startup voltage (about 500 mV) and current (< 2uA), whose frequency can be affected through changes in inductance or capacitance from the user interactions. Multiple MARS systems can operate in the same environment by tuning each oscillator circuit to a different frequency range. The nanowatt power budget allows the system to be powered directly through ambient energy sources like photodiodes or thermoelectric generators. We differentiate MARS from previous systems based on power requirements, cost, and part count and explore different interaction and activity sensing scenarios suitable for indoor environments.

中文翻译：

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MARS：用于触摸、滑动和语音输入的 Nano-Power 无电池无线接口

使用免维护、低成本（约 1 美元）和合适的外形尺寸的交互感应能力来增强日常表面是当前技术的挑战。MARS（多通道环境供电实时传感）通过将纳瓦可编程振荡器与频移模拟反向散射通信相结合，实现了触摸、滑动和语音交互的无电池传感和无线通信。零阈值电压场效应晶体管 (FET) 用于创建具有低启动电压 (约 500 mV) 和电流 (< 2uA) 的振荡器，其频率会受到用户交互中电感或电容变化的影响. 通过将每个振荡器电路调谐到不同的频率范围，多个 MARS 系统可以在同一环境中运行。纳瓦功率预算允许系统直接通过环境能源（如光电二极管或热电发电机）供电。我们根据功率要求、成本和部件数量将 MARS 与以前的系统区分开来，并探索适合室内环境的不同交互和活动感应场景。