Ultrasound channel sounding experiments in TNO

For the development of the Smart Acoustic Wearable System demonstrator, channel soundings and ambient noise measurements were performed recently at the TNO premises in The Hague with assistance from NXP and Elliptic Labs. During this channel sounding campaign, ultrasound probe signals in two bandwidths (2-36kHz & 18-24kHz) were transmitted using a tweeter and received by six microphones. The recordings of these microphone channels are being used to visualize the time-variant acoustic channel and can (in replay) be used for the development of a range of ultrasound applications, e.g., ultrasound secure pairing technology. The measured data is available for all project partners on the shared cloud storage.

Figure 1 – The hardware setup for ultrasound channel soundings.

Figure 2 - Impulse response evolution of the acoustic channel while walking back and forth with the mock-up phone.