A method is provided for determining source match of a test system including an RF source, a vector network analyzer (VNA) and a test port. The method includes connecting a first calibration standard to the test port; generating an RF signal using the RF source, and applying the RF signal to the first calibration standard; measuring a first incident signal of the RF signal at a first receiver of the test system, and measuring a first reflected signal at a second receiver of the test system; connecting a second calibration standard to the test port; measuring a second incident signal of the RF signal at the first receiver of the test system, and measuring a second reflected signal at the second receiver of the test system; and determining the source match of the test system using the first incident and reflected signals and the second incident and reflected signals.