HermesD: A High-Rate Long-Range Wireless Transmission System for Simultaneous Multichannel Neural Recording Applications
HermesD: A High-Rate Long-Range Wireless Transmission System for Simultaneous Multichannel Neural Recording Applications
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DOI：
10.1109/tbcas.2010.2044573
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发表时间：
2010-06-01
影响因子：
5.1
通讯作者：
Meng, Teresa H.
中科院分区：
文献类型：
--
作者：
Miranda, Henrique;Gilja, Vikash;Meng, Teresa H.
HermesD是一种高速率、低功耗的无线传输系统，用于辅助运动残疾和基础运动神经科学的神经修复系统研究。这是我们的“爱马仕系统”的第三代，旨在记录和传输大脑植入电极阵列的神经活动。该系统支持同时传输32个信道的宽带数据，采样速率为30 k/s，12 B/采样，采用频移键控调制，载波频率在3.7至4.1 GHz之间可调，链路范围超过20 m。通道速率为24 Mb/s，比特流包括同步和错误检测机制。功耗约为142 mW，足够低，允许系统连续运行33小时，使用两个3.6 V/1200 mAh的Li-SOCl 2电池。该发射器采用现成的组件设计，并组装在三个28 mm x 28 mm的板中，适合38 mm x 38 mm x 51 mm的铝外壳，比HermesD的初始版本尺寸大大减小。一个7-dBi圆极化贴片天线被用作发射机天线，而在接收机侧，一个13-dBi的圆形喇叭天线。分析了采用圆极化波的优点，并通过室内测量加以证实。接收器是一个独立的设备，由几个子模块组成，并与计算机连接，用于数据采集和处理。它基于超外差架构，包括自动频率控制，使其保持最佳调谐到发射机频率。HermesD通信性能通过误码率测量和眼图图显示。接收机的灵敏度为-83 dBm，误码率为10（-9）。从恒河猴进行多个任务的实验记录显示，无论是在低频（局部场电位）和高频带（动作电位）的神经信号的信号质量与商业采集系统。该系统可以很容易地在信道数量和数据速率方面进行扩展，以适应未来几代的爱马仕系统。
HermesD is a high-rate, low-power wireless transmission system to aid research in neural prosthetic systems for motor disabilities and basic motor neuroscience. It is the third generation of our "Hermes systems" aimed at recording and transmitting neural activity from brain-implanted electrode arrays. This system supports the simultaneous transmission of 32 channels of broad-band data sampled at 30 ks/s, 12 b/sample, using frequency-shift keying modulation on a carrier frequency adjustable from 3.7 to 4.1 GHz, with a link range extending over 20 m. The channel rate is 24 Mb/s and the bit stream includes synchronization and error detection mechanisms. The power consumption, approximately 142 mW, is low enough to allow the system to operate continuously for 33 h, using two 3.6-V/1200-mAh Li-SOCl2 batteries. The transmitter was designed using off-the-shelf components and is assembled in a stack of three 28 mm x 28-mm boards that fit in a 38 mm x 38 mm x 51-mm aluminum enclosure, a significant size reduction over the initial version of HermesD. A 7-dBi circularly polarized patch antenna is used as the transmitter antenna, while on the receiver side, a 13-dBi circular horn antenna is employed. The advantages of using circularly polarized waves are analyzed and confirmed by indoor measurements. The receiver is a stand-alone device composed of several submodules and is interfaced to a computer for data acquisition and processing. It is based on the superheterodyne architecture and includes automatic frequency control that keeps it optimally tuned to the transmitter frequency. The HermesD communications performance is shown through bit-error rate measurements and eye-diagram plots. The sensitivity of the receiver is -83 dBm for a bit-error probability of 10(-9). Experimental recordings from a rhesus monkey conducting multiple tasks show a signal quality comparable to commercial acquisition systems, both in the low-frequency (local field potentials) and upper-frequency bands (action potentials) of the neural signals. This system can be easily scaled up in terms of the number of channels and data rate to accommodate future generations of Hermes systems.