User Manual

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12-14 Confidential - For internal use 99-137719-D
6. Find the phase noise measurements at http://192.168.1.1:8080/fft/fft_data, which
contains information similar to (note the phase_noise value):
<header>
<dbm_offset>49.080</dbm_offset>
<channel_power>
<rx1>-78.333</rx1>
<full_scale>-29.253</full_scale>
</channel_power>
<peak_power>
<rx1>-78.348</rx1>
<full_scale>-29.268</full_scale>
</peak_power>
<peak_freq>10000.000</peak_freq>
<noise_floor>
<rx1>-165.565</rx1>
<full_scale>-116.485</full_scale>
</noise_floor>
<c_no>87.217</c_no>
<phase_noise>-88.010</phase_noise>
<centre_freq>1550000000</centre_freq>
<peak_x>10.000</peak_x>
<spur1>
<freq>-238000.000</freq>
<power>-116.735</power>
</spur1>
<spur2>
<freq>388000.000</freq>
<power>-124.472</power>
</spur2>
<spur3>
<freq>178000.000</freq>
<power>-127.087</power>
</spur3>
<spur4>
<freq>-76000.000</freq>
<power>-129.206</power>
</spur4>
<rbw>1000.000</rbw>
<scaling>
<x_max>1000000.000</x_max>
<x_min>-1000000.000</x_min>
<y_max>-24.268</y_max>
<y_min>-126.485</y_min>
</scaling>
<n_fft_used>2000</n_fft_used>
<no_avg>100</no_avg>
<n_serial>3</n_serial>
</header>
As an example a measurement is made around the highest spurious which is located
at -238 kHz.
7. As the phase noise offset is relative to frequency (peak_freq) the phase noise offset
must be set to -248 kHz by accessing http://192.168.1.1:8080/intif/fftsa/config?pno=-
248000
8. Note that for the best dynamic range for phase noise measurement, the channel
power (full scale) should be in the range -10 to -4 dBFS. This can be achieved by
changing the gain to 20 dB by accessing
http://192.168.1.1:8080/intif/fftsa/config?gain=20
9. Instruct the spectrum analyzer to perform the FFT/measurements by accessing
http://192.168.1.1:8080/intif/fftsa/makefft
10. Verify that the spectrum analyzer is in the idle state and thus the measurements are
done, by accessing http://192.168.1.1:8080/intif/status