A two-point iteration method to predict canopy water content from RF loss

Previous studies have investigated the attenuation of 2.4 GHz radio waves and vegetation, and generated a model to predict RF loss in response to the effective water path (EWP) of both packed leaves and whole tree canopies. Owing to the absence of phase information in the radio signal strength (RSS) it is not possible to directly invert the model to elicit EWP. This paper builds upon previous work and proposes a two-point iteration methodology to predict actual gravimetric water content (Mg) of single tree canopies from RF loss. An investigation for sample tree canopies (including two trees in series) demonstrated Mg explained 72% of the variance in measured RF loss.