Extraction of Phase Information from Magnitude-Only Bio-impedance Measurements Using a Modified Kramers–Kronig Transform

The need for portable and low-cost bio-impedance analyzers that can be deployed in field studies has significantly increased. Due to size and power constraints, reducing the hardware in these devices is crucial and most importantly is removing the need for direct phase measurement. In this paper a new magnitude-only technique based on modified Kramers–Kronig transforms is proposed and tested. Comparison with impedance measurements of fresh and aging tomato samples using a precise industry standard impedance analyzer is carried out and explained. Error and noise analysis of the proposed algorithm are also reported.