Liu Xilin, Zhang Milin, Xiong Tao, Richardson Andrew G, Lucas Timothy H, Chin Peter S, Etienne-Cummings Ralph, Tran Trac D, Van der Spiegel Jan
IEEE Trans Biomed Circuits Syst. 2016 Aug;10(4):874-883. doi: 10.1109/TBCAS.2016.2574362. Epub 2016 Jul 18.
Reliable, multi-channel neural recording is critical to the neuroscience research and clinical treatment. However, most hardware development of fully integrated, multi-channel wireless neural recorders to-date, is still in the proof-of-concept stage. To be ready for practical use, the trade-offs between performance, power consumption, device size, robustness, and compatibility need to be carefully taken into account. This paper presents an optimized wireless compressed sensing neural signal recording system. The system takes advantages of both custom integrated circuits and universal compatible wireless solutions. The proposed system includes an implantable wireless system-on-chip (SoC) and an external wireless relay. The SoC integrates 16-channel low-noise neural amplifiers, programmable filters and gain stages, a SAR ADC, a real-time compressed sensing module, and a near field wireless power and data transmission link. The external relay integrates a 32 bit low-power microcontroller with Bluetooth 4.0 wireless module, a programming interface, and an inductive charging unit. The SoC achieves high signal recording quality with minimized power consumption, while reducing the risk of infection from through-skin connectors. The external relay maximizes the compatibility and programmability. The proposed compressed sensing module is highly configurable, featuring a SNDR of 9.78 dB with a compression ratio of 8×. The SoC has been fabricated in a 180 nm standard CMOS technology, occupying 2.1 mm × 0.6 mm silicon area. A pre-implantable system has been assembled to demonstrate the proposed paradigm. The developed system has been successfully used for long-term wireless neural recording in freely behaving rhesus monkey.
可靠的多通道神经记录对于神经科学研究和临床治疗至关重要。然而，迄今为止，大多数完全集成的多通道无线神经记录器的硬件开发仍处于概念验证阶段。为了准备好实际应用，需要仔细考虑性能、功耗、设备尺寸、鲁棒性和兼容性之间的权衡。本文提出了一种优化的无线压缩感知神经信号记录系统。该系统利用了定制集成电路和通用兼容无线解决方案的优势。所提出的系统包括一个可植入的无线片上系统（SoC）和一个外部无线中继器。该SoC集成了16通道低噪声神经放大器、可编程滤波器和增益级、一个逐次逼近寄存器型模数转换器（SAR ADC）、一个实时压缩感知模块以及一个近场无线电力和数据传输链路。外部中继器集成了一个带有蓝牙4.0无线模块的32位低功耗微控制器、一个编程接口和一个感应充电单元。该SoC以最小化的功耗实现了高信号记录质量，同时降低了经皮连接器感染的风险。外部中继器实现了最大程度的兼容性和可编程性。所提出的压缩感知模块具有高度可配置性，在压缩比为8倍时的信噪失真比（SNDR）为9.78 dB。该SoC已采用180纳米标准互补金属氧化物半导体（CMOS）技术制造，占据2.1毫米×0.6毫米的硅面积。已组装了一个植入前系统来演示所提出的范例。所开发的系统已成功用于自由活动的恒河猴的长期无线神经记录。
