SAW high frequency resonators & oscillators
The Frequency Control Products Group has a powerful capability for the design and manufacture of space-qualified SAW resonators, which are used in SAW notch filters and SAW oscillators.
SAW oscillators can be implemented at substantially higher frequencies than quartz crystal oscillators, whilst retaining quartz’s intrinsic frequency/temperature stability. The devices offer excellent phase noise and frequency stability. A SAW voltage-controlled oscillator can be readily phase-locked to a crystal reference, giving a composite UHF source with the frequency stability of the reference and optimum close-in and far-out phase noise.
SAW resonator technology also allows passive UHF notch filters for suppression of unwanted signals to be implemented.
Features / technical details
Notch Filters
- Flexible frequency range in the UHF band
- Quartz temperature stability
- Simple construction, compact, robust
- Typically used for LO rejection in up-converters
SAW Oscillators
- Quartz temperature stability
- Low noise analogue RF and precision DC control circuitry in surface-mount format
- Can be phase-locked, eg to a quartz reference oscillator, for an optimum phase noise UHF source
- Very light and compact
- Radiation tolerant
- Mechanically robust – to withstand launch vibration and solar panel deployment etc
Performance
| Frequency range | 100MHz – 1GHz |
| Stability (all-causes) | <±100ppm |
| Frequency/temperature stability | Parabolic, Δf/f = -0.03 (T-T0)2 ppm |
| Ageing | <±5x10-9/day |
| Phase noise | -165 dBc/Hz @ 100 kHz |
| Power consupmtion | 300 mW |
| Output power | 10 dBm |
| Harmonics | <-30 dBc |
| Size | 38 x 32 x 8mm |
| Mass | 20 grams |
Benefits
- Radiation tolerant – total dose and prompt radiation
- Mechanically robust – to withstand launch vibration and solar panel deployment
Interfaces
- SAWO EFC suitable for telecommand
- SAWO can be phase-locked, e.g. to a quartz master oscillator
- Custom packaging e.g. surface-mount using Astrium proprietary MMHT hybrid format, or as a boxed unit with RF connectors
Environment
- G-sensitivity: <1x10-9/g
- Operating temperature: -30°C to +85°C
- Radiation tolerance: >100 krad
Categories
Applications
- Low noise UHF VCOs
- Notch fliters, e.g. for LO rejection
Reference customers
Inmarsat-4
