FPGA implementation of adaptive beamforming in hearing aids

Area of Science:

• Signal Processing
• Acoustics
• Biomedical Engineering

Background:

• Beamforming is crucial for hearing aid performance, enhancing speech clarity by filtering sound.
• Existing hearing aid beamforming architectures require optimization for improved noise reduction.

Purpose of the Study:

• To propose and implement improved adaptive beamforming techniques for hearing aid applications.
• To enhance the signal-to-noise ratio (SNR) in noisy environments.

Main Methods:

• Developed an improved architecture for a two-omnidirectional microphone array based adaptive beamforming system.
• Implemented the system on a Xilinx Artix 7 FPGA using VHDL and Xilinx Vivado.
• Introduced adaptive null steering by combining fixed polar patterns to target noise sources.

Main Results:

• Demonstrated effective noise reduction through adaptive null steering.
• Achieved significant improvements in signal-to-noise ratio (SNR) values.
• Experimental analysis confirmed the effectiveness of the proposed beamforming patterns in a conference room setting.

Conclusions:

• The enhanced adaptive beamforming architecture offers superior performance for hearing aid applications.
• The FPGA implementation provides a viable solution for real-time noise suppression in hearing devices.
• Adaptive null steering is a key technique for improving audibility in complex acoustic environments.