A method for training a model for use in monitoring a health parameter in a person is disclosed. The method involves receiving control data that corresponds to a control element, wherein the control data corresponds to a health parameter of a person, receiving stepped frequency scanning data that corresponds to radio waves that have reflected from the control element, wherein the stepped frequency scanning data includes frequency and corresponding amplitude and phase data over a range of frequencies, generating training data by combining the control data with the stepped frequency scanning data in a time synchronous manner, and training a model using the training data to produce a trained model, wherein the trained model correlates stepped frequency scanning data to values that are indicative of a health parameter of a person.