Anritsu Series MS278XB To Noise Ratio Calculated Phase Noise Specification Offset, DBc DBc/Hz

Operation Verification Measurements

10.On the MS2781B, set Peak to CF and then set Peak to Reference Level.

11.Set the MS2781B to Single Sweep mode, press the Sweep button, and then wait for the 200 sweeps to complete.

12.Turn on Marker 1 and Marker 2. Make Marker 2 as delta marker referenced to Marker 1.

13.Move Marker 2 to the first offset frequency from the carrier frequency. Record the marker reading in the measured dBc column.

14.Calculate the normalized phase noise using the formula in the Calculated Phase Noise column. Verify that the calculated value is within specification.

15.On the MS2781B, set Span and RBW to the next set of values in Table 5-7.

16.Press the Sweep button to initiate a sweep.

17.Move Marker 2 to the next offset frequency. Record the delta marker reading in the Measured Carrier to Noise Ratio column.

18.Calculate the phase noise and verify that the value is within specification.

19.Repeat steps 15 through 18 for the rest of the offset frequencies listed in Table 5-7.

Table 5-7.	Single Sideband Phase Noise Test
				Measured Carrier
				to Noise Ratio	Calculated Phase Noise	Specification
Offset		Span	RBW	C/N (dBc)	(dBc/Hz)	(dBc/Hz)
100 Hz		250 Hz	10 Hz		C/N–10 dB=	< –90
1 kHz		2.5 kHz	100 Hz		C/N–20 dB=	< –109
10 kHz		25 kHz	1 kHz		C/N–30 dB=	< –116
100 kHz		250 kHz	10 kHz		C/N–40 dB=	< –116

20.Turn off Marker 2.

21.Record the Marker 1 power as the Measured Carrier Power in Table 5-8.(Use this to compute the Measured Carrier to Noise Ratio in Step 24.)

22.For frequency offsets ≥1 MHz, set the MS2781B as follows:

a.Frequency Span: 1 kHz

b.Reference Level: –25 dBm

c.RBW: 10 kHz

d.VBW: Auto

e.Sweep Time: 120 Seconds

f.Attenuation: 0 dB

g.Trace Mode: Clear-Write

h.Detector: RMS

i.Optimize Phase Noise: Manual

j.Optimize Phase Noise Offset: >85 kHz

23.Set the Center Frequency as indicated in Table 5-8and initiate a sweep.

24.After the sweep passes Marker 1, record the difference between the marker value and the Measured Carrier Power as the Measured Carrier to Noise Ratio in Table 5-8.

25.Repeat Step 23 and Step 24 for the rest of the Center Frequencies listed in Table 5-8.

5-82 MS278XB OM