Bias Tee When Making 2-Port Gain Measurements - Anritsu MS2024B Manual

Bias Tee, Option 10

10-4 Bias Tee when Making 2-Port Gain Measurements

10-4 Bias Tee when Making 2-Port Gain Measurements
Two power levels are available with 2-port measurements: High and Low. The Low Port
Power setting should be used when making direct gain measurements of amplifiers. This will
help to ensure that the amplifier is operating in the linear region. The High Port Power
setting (default setting) is ideal when characterizing passive devices but can also be used
when making relative gain or antenna-to-antenna isolation measurements in the field. For
performance details and measurement uncertainties, refer to the Technical Data Sheet
(Anritsu part number 11410-00501).
The internal bias tee is typically used to put voltage on the RF port that is feeding the bias to
the amplifier under test. Because of its full reversing architecture, the MS20xxC VNA Master
can support amplifier measurements with the amplifier input connected either to Port 1 or to
Port 2. To support this flexibility, the internal bias tee can be directed to either port via a user
selection. Each port selection has its own Voltage setting and Current Limit setting that can
be saved with the setup (refer to Figure 10-4).
Figure 10-4. S21 Log Magnitude (VNA Measurement Menu)
The voltage setting for the internal bias tee, when selected for either port, can be set from
12.0 VDC to 32.0 VDC in steps of 0.1 V. The Current Limit value, with a maximum setting of
450 mA, sets the trip point. If the current draw of the device under test exceeds this trip point
level, then the VNA Master shuts off the internal bias tee, the LED indicator on the connector
panel turns from green to flashing red, and the actual voltage and current readings that are
displayed on the screen turn red.
Vector Network Analyzer MG PN: 10580-00289 Rev. K 10-5