Ultrastable Microwave Generator



Advanced Features and Benefits

  • Complete robust solution, comprising an ultrastable laser and an optical frequency comb
  • Fully remotely controllable
  • Customizable, with the possibility to equip the unit with multiple outputs, both optical and RF/Microwave frequencies
  • Highest stability

    System schematic UMS Compact rev02
  10 MHz
100 MHz 10 GHz   10 MHz 100 MHz 10 GHz
Offset frequency (Hz)       Averaging time (s)      
1 -140 -125 -95 0.1 <3E-14 <5E-14  <3E-15
10 -150 -135 -115 1 <3E-14  <5E-14  <3E-15
100 -155 -145 -130 10 <1E-13 <1E-13 <1E-14 
1k -165 -150 -145 100 <5E-13 <5E-13 <1E-13
10k -165 -155 -160 1000 <5E-12 <5E-12 <1E-12
100k <-165 -155 <-160 >10000 <5E-11 <5E-11 <1E-11
1M <-165 -155 <-165        
System can be equipped with GPS receiver for long-term steering. De-drift function can be configured for handover at the appropriate time to a more stable reference.
*Inquire for residual.



Ultrastable Microwave System: photonic microwave technology representing a paradigm shift in microwave signal synthesis. This groundbreaking advancement is the first commercially-available photonic microwave source that utilizes the phase-coherent division of high-fidelity optical signals into the microwave domain. By employing this innovative approach, we can drastically reduce optical phase noise to levels that were previously physically impossible with more established technologies like multiplied OCXOs or room-temperature Sapphire oscillators.

The UMS-Compact is the bigger brother of the UMS-Mini. It also includes a fully autonomous ultrastable laser and a frequency comb, in a robust custom-designed rack-system to be operated in telecom cabinets, radar and radio-astronomy domes. It allows for the addition of customizable extensions for multiple frequency outputs, both in RF/Microwave or for comb-line synthesis at specific optical frequencies. The UMS-Compact can be further synchronized, on request, to optical or microwave signals as inputs, making it an ideal flywheel for metrological fiber networks and RF over fiber nodes. It is the follow-up system to the Menlo device featured in Jahangir et al.*.

*M. Jahangir et al.: Building a Quantum-Enabled, Networked Radar Testbed for Urban Surveillance of Low Observable Aerial Targets – Current Status;
10th Military Sensing Symposium (NATO STO, 2023)

Left Phase Noise

Absolute phase noise specifications for a 10 GHz carrier signal delivered by the UMS-Compact and UMS-Mini, in comparison with the best on the market upscaled OCXO.


Right modallan


Absolute frequency stability of the 10 GHz signal delivered by the UMS-Compact and UMS-Mini. The optical stability of the reference system is also shown.

Menlo Expert Ben Sprenger 2019
Dr. Benjamin Sprenger
Your direct line to our expert

Data sheets

Ordering information

  • Product Code
  • UMS-Compact

+49 89 189166 0

Menlo Systems, Inc.
+1 973 300 4490

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