Low-Cost Continuous-Wave Radar System Design for Detection of Human Respiration Rate

Radar systems for medical applications are widely researched and developed. One application of this radar is to measure human vital conditions such as respiratory rate. Therefore, a system that can detect human respiratory rate is in need. In this study, a continuous-wave radar was designed with a LoRa RFM95 as a transmitter at 862–1020 MHz frequency and RTL-SDR as a receiver as well as an analog to digital converter. The antenna used in this study are two single elements rectangular microstrip patch antennas, each for transmitting antenna and for receiving antenna designed center frequency of 915 MHz. The methods used to obtain human respiratory rate are complex demodulation magnitude. Experiment shows that this radar can obtain human respiration successfully.