Rizk Michael, Obeid Iyad, Callender Stephen H, Wolf Patrick D
Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA.
J Neural Eng. 2007 Sep;4(3):309-21. doi: 10.1088/1741-2560/4/3/016. Epub 2007 Jul 20.
A fully implantable neural data acquisition system is a key component of a clinically viable cortical brain-machine interface. We present the design and implementation of a single-chip device that serves the processing needs of such a system. Our device processes 96 channels of multi-unit neural data and performs all digital processing necessary for bidirectional wireless communication. The implementation utilizes a single programmable logic device that is responsible for performing data reduction on the 96 channels of neural data, providing a bidirectional telemetry interface to a transceiver and performing command interpretation and system supervision. The device takes as input neural data sampled at 31.25 kHz and outputs a line-encoded serial bitstream containing the information to be transmitted by the transceiver. Data can be output in one of the following four modes: (1) streaming uncompressed data from a single channel, (2) extracted spike waveforms from any subset of the 96 channels, (3) 1 ms bincounts for each channel or (4) streaming data along with extracted spikes from a single channel. The device can output up to 2000 extracted spikes per second with latencies suitable for a brain-machine interface application. This device provides all of the digital processing components required by a fully implantable system.
完全植入式神经数据采集系统是临床可行的皮层脑机接口的关键组成部分。我们展示了一种满足此类系统处理需求的单芯片设备的设计与实现。我们的设备可处理96通道的多单元神经数据，并执行双向无线通信所需的所有数字处理。该实现利用单个可编程逻辑设备，负责对96通道的神经数据进行数据精简，为收发器提供双向遥测接口，并执行命令解释和系统监控。该设备以31.25 kHz采样的神经数据作为输入，并输出包含将由收发器传输的信息的线路编码串行比特流。数据可以以下四种模式之一输出：(1) 从单个通道流式传输未压缩数据，(2) 从96通道的任何子集中提取的尖峰波形，(3) 每个通道的1 ms计数，或(4) 流式传输数据以及从单个通道提取的尖峰。该设备每秒最多可输出2000个提取的尖峰，其延迟适用于脑机接口应用。该设备提供了完全植入式系统所需的所有数字处理组件。
