Figure 13.

Principle of the Intelligent Microwave Camera

(A and B) An illustrative scenario for monitoring people in a typical indoor environment in a smart, real-time and inexpensive way, where the intelligent metamaterial decorated as a part of wall is used to adaptively manipulate ambient Wi-Fi signals.

(C) In-situ imaging results.

(D) The left panel is the result of the Wi-Fi signals focused at the desirable spot of human hand, and the right panel is the corresponding coding pattern of the programmable metamaterial.

(E) The classification matrix of 10 hand signs.

(F) Results of human respiration of two non-cooperative persons behind a 5-cm-thickness wall. Reference: L. Li, Light (2019)