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/hot-find-DC-Comics-The-Flash-Movie-Batman-Poster-iPhone-14-Pro-Waterproof-Case-p17538-special-save/