Can anybody help me try to understand it? I imagine they play a white noise and use their directional mics to get the result of interference of white noise and

Can anybody help me try to understand it? I imagine they play a white noise and use their directional mics to get the result of interference of white noise and breathing sounds. But "noise is reflected back" makes it seem like radar. Why is it not sonar/radar then? And with "With this skill, called BreathJunior", it makes it sound like existing smart speakers can do it. This has nothing to do with smart speakers right?