Systems and methods for TDR using standing waves and an injected test signal

Systems and methods provide for a network test that by capturing in-phase values of a reflected signal off a transmission medium or irregularity therein. The in-phase values are converted to time-domain, which is then halved and converted back to the frequency domain to identify calculated quadrature values associated with the measured in-phase values. The measured in-phase values and calculated quadrature values may be used to determine impedance reflection/transmission characteristics of transmission medium or an irregularity therein. The measured in-phase values and calculated quadrature values may be used to determine if the transmission medium is minimum phase.