As a result of years of research, Novus offers several stability options for many of its standard platforms. Each option addresses variables that compromise reference performance — such as receiver characteristics, power conditioning, timing resolution, and vibration. These environmental factors can impact stability, and addressing them involves cost. Below is an overview of the available stability performance options.
Note: Not all options are available on all products — contact the factory for assistance.
Stability Performance Options
Method Option | GNSS Locked | PLL | PULSE Stabilization | Temp Control | Vibration Isolation | ADEV (1 s) | ADEV (100 s) | ADEV (1 ks) | ADEV (100 ks) |
---|---|---|---|---|---|---|---|---|---|
HS0 | ● | 3.00E-10 | 5.00E-10 | 8.00E-12 | |||||
HS1 | ● | 3.00E-12 | 2.00E-11 | 5.00E-12 | 5.00E-12 | ||||
HS2 | ●● | Option | 3.00E-12 | 1.00E-11 | 4.00E-12 | 9.00E-13 | |||
HS3 | ●●● | Option | 3.00E-12 | 7.00E-12 | 4.00E-12 | 7.00E-14 |
HS0 – Analog Loop
This basic reference option is sufficient for many applications. The OCXO is controlled through the following signal path:
- GNSS Receiver →
- 10 MHz Synthesizer →
- Standard 10 MHz Locked Reference →
- Loop Network →
- OCXO
This analog loop provides strong OCXO control. GaAs mixers offer excellent phase performance, but filtering size and mixer drive limitations make close-in phase noise more challenging.
HS1 – Digital Loop
Using a microprocessor instead of analog components improves performance:
- GNSS Receiver →
- High-Performance Processor →
- PPS →
- OCXO DAC →
- Synthesizer
This digital loop offers longer, adaptive time constants. It improves both Allan Deviation and close-in phase noise versus the analog design.
HS2 – Improved Pulse Stabilization
This configuration enhances resolution using a 20 psec comparator:
- GNSS Receiver →
- High-Performance Processor →
- PPS →
- OCXO DAC →
- Synthesizer
This architecture improves both short-term stability and pulse-to-pulse jitter performance, further refining Allan Deviation metrics.
HS3 – Advanced Stabilization
The most advanced stabilization option available, HS3 includes:
- Gaussian GNSS Receiver (50+ channels)
- Picosecond resolution
- Ultra-low noise DAC
- Thermal and optional vibration isolation
The entire control system is thermally isolated and can be vibration-isolated to eliminate noise from fans and environmental vibrations. This configuration delivers industry-leading stability and low noise performance.