Novel monolithic-microwave integrated-circuit source-impedance tuners for u
se in on-wafer noise-parameter measurement systems are reported, which can
be incorporated into a wafer probe tip. These eliminate the effect of cable
and probe losses on the magnitude of a reflection coefficient that can be
presented to the input of an on-wafer test device, thus enabling higher mag
nitudes to be synthesized than for conventional tuners, and with the potent
ial of increasing noise-parameter measurement accuracy.