Performance Measurements
Phase Noise Profiles and Spectrum Graphs
Reference Clock Tx
Test Conditions
The Ref Clock is configured with an internal 10 MHz reference. However after accounting for the divide by 2 and clock buffer, it operates at 5 MHz. A 50R cable was used to hook up the Crimson TNG to an oscilloscope. We then captured the output on the oscilloscope.
Results
Figure 1: Phase Noise of Reference Clock
Figure 2: Spectrum of Ref Clock
Dev Clock Tx
Test Conditions
The Dev Clock, used for converters, operates at 325MHz (Configured with internal 10MHz reference). A 50R cable was used to hook up the Crimson TNG to an oscilloscope. We then captured the output on the oscilloscope.
Results
Figure 3: Phase Noise profile of Dev Clock
Figure 4: Spectrum of Dev Clock
Tx Waveforms
Test Conditions
We use the tx_waveforms program that comes preinstalled with libUHD (It can be found here) to generate waves on the Crimson TNG device. The TxA output channel was then connected via a 50R SMA cable to an oscilloscope from which we captured the output.
Using the Crimson Web UI, we also set the NCO Frequency to 10.16250.
The Tx waveforms program was run with the following parameters:
| Attribute | Variable name | Value |
|---|---|---|
| Rate | rate |
16 250 000 |
| Amplitude | ampl |
0.7 |
| Gain | gain |
11.25 |
| Wavetype | wave-type |
SINE |
| Wave Frequency | wave-freq |
10 000 |
| Channels | channels |
“0” |
For example, this was the command used to generate a 50 MHz wave:
sudo ./tx_waveforms \
--rate 16250000 \
--ampl 0.7 --gain 11.25 \
--wave-type SINE \
--wave-freq 100000 \
--channels "0" \
--freq 50000000
Results
Figure 5: Phase Noise Profile of 50 MHz Tx Waveform on Crimson TNG
Figure 6: Spectrum of 50 MHz Tx Waveform on Crimson TNG
Figure 7: Phase Noise Profile of 500 MHz Tx Waveform on Crimson TNG
Figure 8: Spectrum of 500 MHz Tx Waveform on Crimson TNG
Figure 9: Phase Noise Profile of 1500 MHz Tx Waveform on Crimson TNG
Figure 10: Spectrum of 1500 MHz Tx Waveform on Crimson TNG
Figure 11: Phase Noise Profile of 2800 MHz Tx Waveform on Crimson TNG
Figure 12: Spectrum of 2800 MHz Tx Waveform on Crimson TNG
Figure 13: Phase Noise Profile of 4200 MHz Tx Waveform on Crimson TNG
Figure 14: Spectrum of 4200 MHz Tx Waveform on Crimson TNG
Figure 15: Phase Noise Profile of 5100 MHz Tx Waveform on Crimson TNG
Figure 16: Spectrum of 5100 MHz Tx Waveform on Crimson TNG
Rx Max Sensitivity
Test Conditions
The Rx measurements phase noise measurements are split into two setups. The first setup shows the maximum sensitivity capabilities while the second setup shows the maximum dynamic range Capabilities. In the first setup, we generated a low power signal on a signal generator and passed it into Rx Channel A on the Crimson TNG. The signal is captured with theunder a high gain setting at 0 attenuation setting using a gnuradio program (alongside some overrides in the Web UI).
Results
Figure 17: Spectrum of 50 MHz Rx Waveform under Max Sensitivity conditions
Figure 18: Spectrum of 500 MHz Rx Waveform under Max Sensitivity conditions
Figure 19: Spectrum of 1500 MHz Rx Waveform under Max Sensitivity conditions
Figure 20: Spectrum of 2800 MHz Rx Waveform under Max Sensitivity conditions
Figure 21: Spectrum of 4200 MHz Rx Waveform under Max Sensitivity conditions
Figure 22: Spectrum of 5100 MHz Rx Waveform under Max Sensitivity conditions
Rx Dynamic Range
Test Conditions
The Rx measurements phase noise measurements are split into two setups. The first setup shows the maximum sensitivity capabilities while the second setup shows the maximum dynamic range Capabilities. In the second setup, we generated a high power signal on a signal generator and passed it into Rx Channel A on the Crimson TNG. The signal is captured with theunder a low gain setting at -31.7 attenuation setting using a gnuradio program (alongside some overrides in the Web UI).
| Parameter | Value | Where is it set? |
|---|---|---|
| Signal Power | 0 dBm | Signal Generator |
| LNA Enable | Yes | Web UI |
| Gain | 0 dBm | Web UI |
| Attenuation | -31.7 dBm | WebUI |
| Sample Rate | 325 000 000 / 100 | gnuradio |
Results
Figure 23: Spectrum of 50 MHz Rx Waveform under Max Dynamic Range conditions
Figure 24: Spectrum of 500 MHz Rx Waveform under Max Dynamic Range conditions
Figure 25: Spectrum of 1500 MHz Rx Waveform under Max Dynamic Range conditions
Figure 26: Spectrum of 2800 MHz Rx Waveform under Max Dynamic Range conditions
Figure 27: Spectrum of 4200 MHz Rx Waveform under Max Dynamic Range conditions
Figure 28: Spectrum of 5100 MHz Rx Waveform under Max Dynamic Range conditions
