A timing critical SYNC pulse is needed to trigger synchronization.
Figure 3-3. Timing Critical SYNC Pulse
Figure 3-4. Output Phases After Synchronization
3.2 Phase Noise Improvement
By combining the output of two synthesizers that are in-phase, a theoretical 3-dB phase noise benefit is possible
due to the output power being 6-dB higher while the noise power is only 3-dB higher.
To measure the combined phase noise, some modification to the EVM is needed. See
for details.
In
, the blue trace shown the phase noise of individual LMX2594 device while the black trace
respresented the phase noise of the combined signal.
Typical Measurement
SNAU278 – JULY 2022
LMX2594PSEVM Evaluation Instructions
7
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