Figure 4
From: Non-contact diagnosis of obstructive sleep apnea using impulse-radio ultra-wideband radar
Normalized respiratory signals from PSG (nasal airflow and abdominal movement) and IR-UWB radar: IR-UWB radar can be used to detect three types of apneas (A) central, (B) obstructive, (C) mixed, and (D) hypopnea.
