Current wireless sensing systems mainly rely on batteries as power source, which requires extensive maintenance resources. Battery-less self-powered wireless sensing system is a promising technology to solve this problem with real-time sensing capability. However, most of the systems can not simultaneously achieve multi-parameter omnidirectional wireless sensing with high sensing stability, and adequate transmission distance. Here, a self-powered dual-parameter omnidirectional wireless sensing system is proposed. By utilizing a compact symmetrical resonant circuit, pulsed output of a triboelectric nanogenerator can be modulated into a decaying resonant signal with two resonance frequencies that are independently correlated to variations of the sensors. The decaying resonant signal is then transmitted through a spark microswitch wirelessly and omnidirectionally with a distance well over 5 m. Compared with previous works, the proposed system shows the most comprehensive capabilities encompassing omnidirectional wireless transmission, multi-parameter sensing, high sensing stability, and long transmission distance at the same time. A preliminary humidity/liquid level dual-parameter wireless sensing demonstration is conducted, and the sensors exhibits high sensing accuracy and stability, showing its great potential for applications.

中文翻译：

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基于对称谐振电路的无电池自供电双参数全向无线传感系统

目前的无线传感系统主要依靠电池作为电源，需要大量的维护资源。无电池自供电无线传感系统是解决这一问题的一项有前途的技术，具有实时传感能力。然而，大多数系统无法同时实现高传感稳定性和足够的传输距离的多参数全向无线传感。这里，提出了一种自供电双参数全向无线传感系统。通过利用紧凑的对称谐振电路，摩擦纳米发电机的脉冲输出可以被调制成具有与传感器的变化独立相关的两个谐振频率的衰减谐振信号。然后，衰减的谐振信号通过火花微动开关以无线方式全向传输，距离远超过 5 m。与之前的工作相比，该系统显示出最全面的能力，同时涵盖全向无线传输、多参数传感、高传感稳定性和长传输距离。进行了初步的湿度/液位双参数无线传感演示，传感器表现出较高的传感精度和稳定性，显示出其巨大的应用潜力。