||Conventional architectures have encountered serious challenges such as cost, system complexity, and power consumption. Therefore, to potentially overcome these disadvantages, this thesis proposes a continuous-wave (CW) radar architecture in a Self- and Mutually Injection-Locked (SMIL) state. Since the setup of two radars on different sides of the human body is often limited by the measurement environment in the practical application process, we presents two different antenna setups to solve this problem. This thesis demonstrated a Doppler radar system for monitoring vital signs in real time transmitting a continuous-wave (CW) signal. The Doppler phase-shifted signal that is partially reflected by a distant human subject and then injected into the VCO. Therefore, The radar system will generate a frequency modulated signal which caused by vital signs of a human body. The modulated signal will be demodulated through the frequency demodulator. When subjects are in the process of measurement , they can easily observe the rates of respiration and heartbeat in the spectrum and oscilloscope. The VCO that was design for the radar system was operated in the Industrial Scientific and Medical (ISM) bands from 2.36 to 2.484 GHz.|
In the first part, we will study the system architecture, theoretical model and antenna setup of the SMIL radar. Two conducting plates was used with the actuator for calibrating two separate antennas. the system can remove in real time the effects of random body movement on the monitoring of vital signs from one side of the human body. A comparison of the experiment data can let us understand the cancellation difference between each antenna setup. In the second part, According to the previous design architecture and specification, we design the transmitter and receiver by ourselves and then constitute a SIL radar system. By using the the spectrum and oscilloscope in the process of real-time vital sign monitoring, we will know more about the differences between each radar system. Finally, we will explore the causes of the experiment result between each radar system and find the proposed method for improving the radar system.