Dielectric measurement of logs for improved internal imaging

This paper describes the measurement of the dielectric properties of the typical log features of Heartwood, Sapwood and internal Branches. Measurements were made using the waveguide cell technique covering the frequency range of 2.3 to 6.5GHz. This has shown that for the desired contrast between heartwood and Sapwood to be achieved the imaging system must operate above 4GHz. Additional work was undertaken to establish a method to correct these measurements for variations in basic density and EarlywoodLatewood banding, giving rise to a potential moisture content estimation error of 0.63%. This will lead to improved spatial location of features of interest.