The heart and breathing rate of a person can be monitored by using the reflection coefficient phase of an antenna attached parallel to the chest of a person. The effect of frequency, power and the antenna type on the accuracy of heart rate detection is determined. The feasibility of this technique to measure heart rate variability is tested. Its ability to calculate respiration rate is also demonstrated. It is found out that this technique holds promise for the measurement of vital signs and heart rate variability and thus can be a useful addition to home healthcare.