In practical situations such as hostage rescue. earthquake and other similar events. the ultra-wideband (UWB) life-detection radar echo response from the respiration motion of the trapped person is always quasi-/non-periodic in respiration frequency or very weak in respiration amplitude. which can be called quasi-static vital sign. https://www.bekindtopets.com/flash-choice-Sensationnel-Empire-Bump-100-Human-Hair-Weave-FEATHER-WRAP-8-mega-find/