The use of millimeter wave radar (mm-wave) for various purposes continues to increase. One of them is the use of radar in detecting vital sign of breathing. Non-contact respiratory detection can provide benefits in broader fields such as disaster mitigation in the process of detecting victims behind ruins, the health sector as a more hygienic patient breathing monitoring and providing comfort for patients, and the military sector supports the recognition of enemies hiding behind walls.
Radar Frequency Modulated Continuous Wave (FMCW) has advantages such as the ability to detect multiple targets, better resolution range, simple transmitter architecture, and resistance to intercept. Efforts to increase the capability of the FMCW multi-target radar in identifying small displacement respirations continue to be developed. One of these efforts is to increase the ability of the transceiver device so that it can produce several antenna beam directions that can reach targets in different directions. Beamforming