An apparatus detects and measures vital signs of each human target by a continuous, non-intrusive method. In an example, the vital signs of interest include a heart rate and a respiratory rate, which can provide valuable information about the human's wellness. Additionally, the heart rate and respiratory rate can also be used to identify a particular person, if more than two target humans are living in a home. The apparatus has a natural convection spatial flow path that draws heat from at least one processor, one fan-less radar and a heat sink.