A system adapted to measure electrical performance of a device under test (DUT) having two or more ports includes a plurality of signal sources synchronized and configured to generated signals simultaneously, a plurality of first signal paths to obtain transmitted and reflected signals from the DUT, a plurality of second signal paths to obtain incident signals from the signal sources, and a receiver for receiving the reflected, transmitted and incident signals obtained at the first signal paths and the second signal paths. The receiver is adapted to separate the reflected and the transmitted signals obtained from each of the first signal paths. The signal sources are configured to each generate a signal having a frequency offset from each of the others of the signal sources by a known frequency delta.