Three-Port Measurement
3-Port devices such as duplex filters and power dividers can be measured with the VNA-0440e and the VNA-0460e, that have an extra generator port.
TheVNA-0440e and VNA-0460e will do a 2½-port measurement and measure S11, S12, S13, S21, S22, S23. The other s-parameters S31, S32 and S33 can be measured by changing the device around.