Making Measurements

Using the Power Sensor

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.

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MA24106A UG

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Anritsu 0701012, MA24106A manual Zeroing the Sensor, Calibrating the Sensor, Applying a Calibration Factor Correction