That's not imaging, that's tracking a WiFi equipped target. That's pretty standard now. Sony's Mocopi is probably the most elegant implementation.[1] Tundra Tracker [2] also gets good reviews.
Motion detection is much lower rez. Ultrasound is like trying to sense the world with a probe the size of a broom.
> Our system tracks free-form activity by estimating a 3D skeleton pose that consists of a set of joints of the human body. In particular, Winect first identifies the moving limbs by leveraging the signals reflected off the human body and separates the entangled signals for each limb. Then, our system tracks each limb and constructs a 3D skeleton of the body by modeling the inherent relationship between the movements of the limb and the corresponding joints. Our evaluation results show that Winect achieves centimeter-level accuracy for free-form activity tracking under various environments.
That's not imaging, that's tracking a WiFi equipped target. That's pretty standard now. Sony's Mocopi is probably the most elegant implementation.[1] Tundra Tracker [2] also gets good reviews.
Motion detection is much lower rez. Ultrasound is like trying to sense the world with a probe the size of a broom.
[1] https://www.youtube.com/watch?v=ovHHpralCD8&t=3s
[2] https://www.youtube.com/watch?v=ImEKHrUp4QM