He Tao, Zheng Yabin, Liang Xu, Li Jiamin, Lin Longyang, Zhao Wenfeng, Li Yongfu, Zhao Jian
Department of Micro/Nano Electronics, Shanghai Jiao Tong University, Shanghai, China.
School of Microelectronics, Southern University of Science and Technology, Shenzhen, China.
Cyborg Bionic Syst. 2023 Aug 8;4:0030. doi: 10.34133/cbsystems.0030. eCollection 2023.
Wearable body sensor nodes require massive data transmission under limited energy. However, it suffers from drastically varying channel loss, which limits its energy efficiency in practical scenarios. This paper presents a power-driven body-channel transceiver (TRX), whose power consumption can be adaptively tuned against varying channel loss. An out-band programmable gain amplifier (PGA) is proposed to save power and generate a quasi-linear correlation between PGA gain and power. By using the quasi-linear gain-power relationship, we propose an auto gain/power control technique to realize on-demand power consumption. In addition, a differential balanced transmitter is designed to eliminate base-band harmonics in on-off keying modulation and increase the power delivered by the transmitter (TX). The TX and receiver (RX) of the prototype were integrated into 1 chip and fabricated in a 55-nm complementary metal oxide semiconductor process. During the measurement, 2 chips were configured as TX and RX, respectively. Both the TX and the RX were wearable, powered by lithium batteries, and attached to the subject's hands. The prototype achieved a 5.25-Mbps data rate with 16-pJ/bit energy efficiency at a 1.5-m straight-line ground path distance. Furthermore, the proposed TRX maintained stable communication within a 1.5-m distance, while dynamically reducing power consumption.
可穿戴人体传感器节点在能量有限的情况下需要进行大量数据传输。然而，它面临着急剧变化的信道损耗，这限制了其在实际场景中的能量效率。本文提出了一种功率驱动的人体信道收发器（TRX），其功耗可以根据变化的信道损耗进行自适应调整。提出了一种带外可编程增益放大器（PGA）以节省功率，并在PGA增益和功率之间产生准线性相关性。通过使用准线性增益-功率关系，我们提出了一种自动增益/功率控制技术来实现按需功耗。此外，设计了一种差分平衡发射机，以消除开关键控调制中的基带谐波，并增加发射机（TX）输出的功率。原型的发射机和接收机（RX）集成在1个芯片中，并采用55纳米互补金属氧化物半导体工艺制造。在测量过程中，2个芯片分别配置为发射机和接收机。发射机和接收机均可穿戴，由锂电池供电，并附着在受试者的手上。该原型在1.5米直线地面路径距离下实现了5.25Mbps的数据速率，能量效率为16皮焦/比特。此外，所提出的收发器在1.5米距离内保持稳定通信，同时动态降低功耗。
