Ultra-Low-Power Links for Brain Probing

This paper discusses signal processing and circuit techniques for ultra-low-power many-channel wireless telemetry. Signal processing has to be performed online to reduce transmit data rate. The choice of signal compression algorithm can greatly reduce energy, much beyond levels attainable by implementation. Since real-time performance required from biomedical implants is much lower than delay of logic gates, computations are done in near-VT regime. Voltage scaling alone does not guarantee high energy efficiency. Architecture design has to position path delay onto pareto-optimal energy-delay curve. Power density levels below 50μW/mm can be achieved. With high signal compression, analog front-end begins to dominate energy consumption.