Multi-Person Breathing Detection With Switching Antenna Array Based on WiFi Signal

Area of Science:

• Wireless communication
• Biomedical engineering
• Signal processing

Background:

• WiFi sensing is a growing technology for vital sign monitoring.
• Existing respiration monitoring systems primarily focus on single individuals.
• There is a need for non-contact, multi-person respiratory monitoring solutions.

Purpose of the Study:

• To develop a WiFi-based system for simultaneous multi-person breathing sensing.
• To enable accurate estimation of respiratory frequency and location for multiple individuals.
• To provide a low-cost, non-contact solution for long-term health monitoring.

Main Methods:

• Utilized a switching antenna array and a reference channel to eliminate phase offsets.
• Employed beamforming for two-dimensional scene scanning.
• Combined Angle of Arrival (AOA) and frequency domain analysis to create an AOA-FREQ spectrogram.
• Applied clustering techniques to identify individual respiratory frequencies and positions.

Main Results:

• Successfully estimated the direction and respiration rate of multiple individuals.
• Demonstrated the capability to monitor abnormal respiration patterns in multi-person scenarios.
• Validated the system's effectiveness in non-contact, multi-person respiratory detection.

Conclusions:

• The proposed WiFi sensing system offers a low-cost, non-contact method for multi-person respiratory monitoring.
• This technology can be applied to long-term home health monitoring, including the detection of abnormal breathing.
• The system effectively addresses the limitations of single-person focused respiration monitoring.