Anritsu 0701012 - Manual (Page 30)

Making Measurements Using the Power Sensor
3-12 MA24106A UG
Zeroing the Sensor
Zero the sensor before making power measurements, particularly when operating within the lower 20 dB
dynamic range of the power sensor. If frequent low-level measurements are being made, it is advised to check
the sensor zeroing often and repeat as necessary. Before zeroing the sensor, connect it to the DUT (device
under test) test port and remove RF power from the connection to a level 20 dB below the noise floor of the
power sensor. For the MA24106A power sensor, this level is less than –60 dBm. It is preferable to leave the
sensor connected to the DUT test port so that ground noise and thermal EMF (electro-magnetic fields) are
zeroed out of the measurement. The sensor may also be connected to a grounded connector on the DUT or
disconnected from any signal source.
To zero the sensor, press the Zero button on the application. If the sensor fails the zeroing operation, the
message box states “Sensor zero failed” and “ZERO_ERROR” will be displayed on the application screen until
the problem is corrected. If RF is detected, a reminder message will pop up asking to remove the RF source.
Calibrating the Sensor
The signal channel/analog signal acquisition hardware is integrated along with the RF front end of the power
sensor. All of the necessary frequency and temperature corrections take place within the sensor. Therefore,
there is no need for a reference calibration (at 50 MHz and 1 mW) with the MA24106A.
Applying a Calibration Factor Correction
The MA24106A power sensor has an internal EEPROM containing correction and calibration factors that were
programmed into the sensor at the factory. The power sensor has an internal temperature sensor that reports
its readings periodically to the microprocessor. The sensor makes all of the required calculations on the
measurement once the measurement frequency has been entered by the user.
Optimizing the Readings
This section presents information on how to get the fastest readings from the MA24106A power sensor when
using the Anritsu Power Meter application or operating under remote control (refer to Chapter 4 for specific
remote programming command descriptions). Measurement speed depends greatly on the type of
measurement, the power level, and stability of the signal. Stability of a measurement is influenced by noise
and signal modulation. If high resolution is required, averaging must be increased.
Note: The values in the following tables are typical and should be used as a reference only.