The linearity correction of the MA24208A and MA24218A is compared to a thermal power sensor, which has very good inherent linearity over a power range of about –17 dBm to +4 dBm. For this reason, the MA24208A and MA24218A is compared to the thermal sensor in three ranges, keeping the power levels to the thermal sensor in the range of –17 dBm to +4 dBm, while the power to the MA24208A and MA24218A varies from about –37 dBm to about +14 dBm.
a. Connect the reference power sensor to the reference power meter using the appropriate cables.
b. Connect the USB cable between the personal computer with the PowerXpert application installed and the MA24208A and MA24218A power sensor under test.
c. Launch the PowerXpert application.
d. Turn the power on to all of the instruments and allow them to warm up for the amount of time specified in the instrument’s respective manuals.
e. Reset or Preset all of the instruments.
f. Configure the reference meter and sensor to measure a CW signal.
g. Perform a sensor Zero and a 1 mW reference calibration on the reference sensor and meter per the manufacturer’s instructions.
h. Connect the power splitter to the output of the synthesizer, and connect the 10 dB attenuator to the reference arm of the splitter output.
i. Connect an N(f) to K adapter (if required) to each power sensor.
j. Connect the reference sensor and adapter to the 10 dB attenuator.
k. Connect theMA24208A and MA24218A and adapter (if required) to the other splitter output.
l. Set the synthesizer CW frequency to 50 MHz.
m. Set the synthesizer leveled output power to +20 dBm or highest leveled power available (do not exceed +20 dBm).
n. Increase averaging of the DUT sensor by entering “16” in the PowerXpert application, and then click Apply above settings.
Linearity Test Setup 3
Index
Description
1
Reference Power Meter
2
Reference Power Sensor
3
K to N Adapter (if required)
4
10 dB Fixed Attenuator
5
Power Splitter
6
K to N Adapter (if required)
7
PC with Anritsu PowerXpert Application
8
Synthesizer
2. Apply the Cal factor to the reference sensor per the manufacturer’s procedure.
3. Apply the Cal factor by entering the frequency of the measurement in GHz.
4. Turn Off the synthesizer’s RF output and perform a low-level Zero of both the Reference sensor and the MA24208A and MA24218A.
5. Turn On the synthesizer’s RF output.
6. Record data for the first 20 dB range as follows:
d. Repeat the measurement of step 6 for synthesizer output levels of +10, +5, and 0 dBm.
Note
The MA24208A and MA24218A power measured at 0 dBm will be used in Step 7e, below.
7. Set up the test for the second 20 dB range as follows:
a. Remove the 10 dB attenuator from in between the reference sensor and splitter and connect the reference sensor (with adapter, if required) directly to the splitter.
b. Remove the MA24208A and MA24218A from the splitter and connect the 10 dB attenuator between the splitter and the power sensor (see Figure: Linearity Test Setup 4).
c. Turn Off the synthesizer’s RF output and perform a low-level Zero of both the Reference sensor and the MA24208A and MA24218A.
d. Turn On the synthesizer’s RF output.
e. Set the synthesizer output level to +10 dBm, then adjust its power level until the sensor/meter under test reads as close as possible to the 0 dBm value recorded in column B row 5. Record the resulting power level in column B, row 6 of Table: Measurement Results (50 MHz).
f. Record the power indicated by the reference meter in column A of row 6.
a. Lower the output power level of the synthesizer to +5 dBm.
b. Record the reference meter and the MA24208A and MA24218A power sensor readings in Table: Measurement Results (50 MHz), columns A and B respectively.
c. Repeat the measurements of step 8 for synthesizer output levels of 0 dBm, –5 dBm, and –10 dBm.
Measurement Results (50 MHz)
Row #
Synth nominal level (dBm)
Atten in Ref Arm (dB)
Atten in Test Arm (dB)
A Ref Power (dBm)
B DUT Power (dBm)
C1
A6–A5 (dB)
C2 A10 –A11 (dB)
C3
B6–B5 (dB)
C4 B11 –B10 (dB)
D
A+C (dBm)
E
B5-D5 (dB)
F
(D-B)+E Diff (dB)
1
20
10
0
2
15
10
0
3
10
10
0
4
5
10
0
5
0
10
0
6
10
0
10
7
5
0
10
8
0
0
10
9
–5
0
10
10
–10
0
10
11
0
0
20
12
–5
0
20
13
–10
0
20
14
max
15
min
16
delta
9. Set up the test for the next 15 dB range as follows:
a. Remove the 10 dB attenuator from in between the splitter and DUT sensor and replace it with a 20 dB attenuator.
b. Turn Off the synthesizer’s RF output and perform a low-level Zero of both the Reference sensor and the MA24208A and MA24218A.
c. Turn On the synthesizer’s RF output.
d. Set the synthesizer output level to 0 dBm (per Table: Measurement Results (50 MHz)), then adjust its power level until the sensor/meter under test reads as close as possible to the value in row10 column B. Record the resulting power level in column B, row 11 of Table: Measurement Results (50 MHz).
a. Lower the output power level of the synthesizer to –5 dBm.
b. Record the reference meter and the MA24208A and MA24218A power sensor readings in Table: Measurement Results (50 MHz), columns A and B respectively.
c. Repeat the measurements of step 10 for synthesizer output levels of –10 dBm.
11. Perform the calculations as follows:
a. Subtract the Reference Power Measurement of row 5, column A from the Reference Power Measurement of row 6, column A. Record this value in the column C1, rows 1 through 5.
Note
Column C1, rows 1 through 5 should all have the same value. The correction column rows 6 through 13 have values of 0.
b. Subtract the DUT power of row 11 column A from that of Row 10 Column A and record in column C2, rows 11 through 13.
c. Subtract the value in row 5 column B from that in row 6 column B. Copy the result into rows 6 through 10 of column C3.
d. Subtract the value of row 10 column B from that in row 11 column B and copy it into rows 11 through 13 column C4.
e. For each row in column D, add the values of the same row of column A and columns C1 through C4 (a blank has value 0 dB).
f. Subtract the value of row 5 column D from that of row 5 column B. Record this values in column E rows 1 thorough 13.
g. For each row in column F compute the value by subtracting the value of column B from that in column D and then adding the value from column E.
h. Find the largest (most positive) value in the column F, rows 1 through 13, and record this value next to the word Max in row14.
i. Find the smallest value in column F, rows 1 through 13, and record this value next to the word Min in row 15.
j. Subtract the Min value from Step 11i from the Max value from Step 11h and record the result next to the word Delta in row 16.
k. The Delta result should be less than 0.3 dB. If it is larger, contact Anritsu customer service.
12. Repeat the entire measurement and calculations with synthesizer frequency settings of 2 GHz, 4 GHz, 6 GHz, 8 GHz, 10 GHz, 12 GHz, 14 GHz, 16 GHz, and 18 GHz.
