The  wireless communication device-based vital-sign radar use the commercial wireless communication devices and their communication signals for the non-contact vital-sign detection in the simplest and lowest cost way. The core of the radar is to use the demodulated signal of the wireless system with an error vector magnitude (EVM) algorithm. This algorithm can extract the vital-signs of the human body around the wireless device from the received  signal without affecting the original communication function. Since the developed vital-sign radar only needs to perform EVM calculation on the received communication signal to detect vital-signs, it has excellent compatibility with commercial wireless communication devices. Because this technique does not need to know the original communication signal in advance during the vital-sign detection process, the developed radar can blind detect vital signs. This property enables the developed radar to detect vital signs actively or passively.

The key breakthrough of the wireless communication device-based vital-sign radar is using a very streamlined EVM algorithm to directly extract the vital signs of the surrounding human body from the received wireless communication signals. Compared with traditional vital-signs radars that require unique microwave circuits, the EVM algorithm can be directly applied to commercial wireless communication devices without modifying the original circuit. In addition, the wireless communication device-based vital-sign radar can also blindly detect the vital signs of the human body around the wireless communication device without transmitting any signal.

The wireless communication device-based vital-sign radar technique can be directly applied to the wireless communication devices which are commonly used by the public. Therefore, the developed vital-sign radar will be more easily accepted by the public than the traditional vital-sign radar. This can prompt the realization of smart cities and smart healthcare. Moreover, the developed vital-sign radar technique can enable any commercial wireless communication devices to detect vital signs without modifying circuits, thus avoiding problems such as increasing cost, power consumption, and electromagnetic interference (EMI).