A low-noise receiver for multichannel wireless neural recording

Area of Science:

• Biomedical Engineering
• Neuroscience Technology
• Wireless Communication Systems

Background:

• Wireless implantable neural recording systems require high-performance receivers for accurate data acquisition.
• Existing systems face challenges in achieving wide bandwidth, extended range, and high data throughput simultaneously.

Purpose of the Study:

• To develop and evaluate a high-performance wideband receiver for multichannel wireless implantable neural recording systems (WINeR).
• To enhance receiver performance, extend its receiving range, and ensure continuous high-throughput data acquisition.

Main Methods:

• Utilized pulse width modulation of time division multiplexed (PWM-TDM) samples.
• Integrated a 50 MHz-1 GHz tunable down-converter with 75 MHz bandwidth, FSK and PWM demodulators, and a high-throughput USB interface.
• Employed IF gain stages, passive LC filters, and an FPGA-based time-to-digital converter (TDC) with 428 ps resolution.
• Incorporated 2 MB SDRAM as a buffer for continuous data throughput up to 10 Mb/s.

Main Results:

• The receiver demonstrated significantly enhanced performance and extended receiving range.
• System input referred noise was measured at 9.8 µV(rms) at 0.5 m and 12.7 µV(rms) at 3.5 m.
• Achieved equivalent resolutions of 8.2 and 7.9 bits at 640 ksample/s at the respective distances.

Conclusions:

• The developed WINeR receiver meets the demanding requirements for multichannel wireless neural recording.
• The system's performance indicates its suitability for advanced neural monitoring applications requiring high fidelity and extended range.