How to handle power line impedance mismatch in a power DTU?

Addressing power line impedance mismatch in DTUs requires the use of an impedance matching network to reduce reflections. The matching network is designed by measuring or calculating the characteristic impedance of the power line (typically 50-600Ω): either through a series resistor (e.g., 50Ω) or by using a transformer for impedance transformation. The transformer turns ratio is determined based on the impedance ratio; for example, from 600Ω to 100Ω, the ratio is √6:1. The matching network is placed at the coupling point. Return loss (S11) is measured using a network analyzer and should be less than -14dB in the carrier frequency band. Addressing impedance mismatch can improve signal transmission efficiency by 20% and reduce radiated emissions by 10dB.