Apply High Density Spectral on ultrasonic

High-density spectral (HDS) data was originated to address vulnerabilities in sound analysis, but its applications are not limited to audible sound.

The attached figure extends the application scope to ultrasonic waves and is used to distinguish various specific signals in ultrasonic range.[red is HDS, green are are FFT, orange is the waveform, sound in 96kHz sampling]

The sample is the friction sound when a metal door is opened and closed. In the past, we could only notice ultrasonic waves generated when metal friction occurs. With the help of HDS, we can distinguish the characteristics of metallic sound in friction within ultrasonic range. This should be the first time to be able to observe this sound in detail. Also those ultrasonic signals aligned in several obvious straight lines, those can be another useful information we have collected from ultrasonic sounds.

For information with higher or lower frequencies than audible sound, HDS can discover more detail while improving the signal-to-noise ratio on short pulses, making the analysis more effective and sensitive.

Being the basis of most signal analysis technologies, HDS can update or push the limits of current technologies, and this technological gap cannot be remedied by other means (even as with Al).

In other words, HDS can be used to alter the direction of science study in various fields, which prevents this technology from being disclosed casually.