The frequency used in the system is another factor that must be considered for the matching. Inductive and capacitive influences cause complex impedance, so frequency must also be considered. Frequency is mandatory when calculating the capacitive and inductive reactance, as shown in the following equations:

Figure 1. Capacitive Reactance

Figure 2. Inductive Reactance

The frequency dependency leads to a matching that is limited in frequency and bandwidth. Thus, during the transformation investigation, it must be considered that all required frequencies are matched to the target impedance.