An Energy-Efficient and High-Data-Rate IR-UWB Transmitter for Intracortical Neural Sensing Interfaces

Area of Science:

• Biomedical Engineering
• Electrical Engineering
• Neuroscience

Background:

• Intracortical neural sensing requires efficient wireless telemetry for brain-computer interfaces.
• Existing systems face limitations in data rate, range, and energy efficiency.

Purpose of the Study:

• To develop an implantable impulse-radio ultra-wideband (IR-UWB) wireless telemetry system for intracortical neural sensing.
• To propose a novel 3-dimensional (3-D) hybrid impulse modulation scheme.

Main Methods:

• A 3-D hybrid modulation combining phase shift keying (PSK), pulse position modulation (PPM), and pulse amplitude modulation (PAM) was developed.
• The transmitter (TX) was implemented in 28 nm CMOS technology, integrating a low-noise injection-locked ring oscillator, a calibration-free delay generator, and a switch-cap power amplifier.
• The system operated in the 6-9 GHz UWB band.

Main Results:

• Achieved a high data rate of 1.66 Gbps and an extended air-transmission range.
• Demonstrated high energy efficiency (5.8 pJ/bit) and excellent modulation quality (EVM < -21 dB).
• Ex-vivo validation showed a communication distance up to 15 cm through 15-mm porcine tissue, with a 16x improvement in distance-normalized energy efficiency (45 pJ/bit/meter).

Conclusions:

• The proposed IR-UWB system with hybrid modulation offers a significant advancement for implantable neural interfaces.
• The system provides a high data rate, extended range, and improved energy efficiency compared to state-of-the-art solutions.
• This technology has the potential to enhance the capabilities of brain-computer interfaces and other implantable medical devices.