Patent attributes
An example front-end module includes a channel to connect to a device under test (DUT). The front-end module includes a transmission line between the DUT and the front-end module that is configured for bidirectional transmission of oscillating signals including test signals and response signals, and in-phase and quadrature (IQ) circuitry configured to modulate a test signal for transmission over the transmission line to the DUT and to demodulate a response received over the transmission line from the DUT. The front-end module include at least four taps into the transmission line to obtain direct current (DC) voltage values based on the oscillating signals. Scattering (s) parameters of the channel are based on the DC voltage values. The front-end module includes at least six ports.