Agilent Technologies 11970-90031 manual Average Noise Level Test

Performance Tests

AVERAGE NOISE LEVEL TEST

For 11970V: 5, 0, GHz

For 11970W: 7, 5, GHz

10.Record the center frequency in Table 3-8.

11.Set the power meter CAL FACTOR to the value shown on the sensor calibration label for the center frequency indicated on the spectrum analyzer.

12.Set the signal generator output to produce a CW signal near the center of the spectrum analyzer display. Next, set the signal generator output power level to produce a reading of approximately -10 dBm on the power meter. Record the power meter reading in Table 3-8. (When testing the 11970V or W, re-zero the power meter for each measurement.)

13.Subtract the coupling factor for the directional coupler from the power meter reading, then add the power meter correction factor (dB) to the power meter reading. Record this corrected power reading in Table 3-8.

Corrected Power Reading = Power Meter Reading - Coupling Factor + Power Meter Correction Factor.

For example:

(-10.03 dBm) - 9.82 dB + 0.73 = -19.1 dBm

14.On the 8566A/B, press MARKER, PEAK SEARCH, then MKR→ REF LVL. Record the marker amplitude in Table 3-8.

15.Move the marker to the displayed noise floor, or turn off the CW signal, and record the marker amplitude in Table 3-8. (Some sources may have excessive wide band noise when the RF signal is turned off, so that the noise floor must be measured with the signal left on.)

NOTE	Step 15 requires a signal source with a wide band phase noise characteristic
	that is at least 6 dB better than the measured average noise level.

16.The Average Noise Level is calculated as follows:

Average Noise Level = Corrected Power Reading (step 13) - Marker Amplitude (step 14) + Marker Amplitude (step 15) - Measurement Bandwidth Correction Factor

11970K, A, Q and U Bandwidth Correction = 10log(l00kHz/ 1 kHz)

11970V and W Bandwidth Correction = 10log(3MHz/ 1 kHz)

For example:

Average Noise Level = (-19.1 dBm) - (-32.3 dBm) + (-77.7 dBm) - 34.77 dB = - 99.3 dBm

17.Enter the calculated value in Table 3-8.

The Average Noise Level must be less than:

-110 dBm (for the 11970K)

-108 dBm (for the 11970A)

Performance Tests

Chapter 3 71