Response to Comments on "Microstrip Characteristic Impedance"(Letters)

Bianco et al. [1] have performed a service in pointing out that microstrip characteristic impedance definitions employing voltage-current-power ratios can be functionally inconsistent. The purpose of my note was to show that such definitions are also inconsistent (with one coincidental exception) with the unifying concept of wave impedance [2], which embraces the impedances of the modes of TEM lines, hollow waveguides, and other structures.