In Space, weight, size and energy consumption matter, and of course always accompanied with reliability and resistance to severe environmental conditions (shock, vibration, radiation, etc). Syrlinks has been one of the first Space OCXO manufacturers to address successfully one of the two 2 mega-constellation of micro-satellite currently in deployment, namely OneWeb. Syrlinks cost effective OCXO for space applications, EWOS5500, is flight proven and offers excellent short term stability for a power consumption limited to 165mW at 25°C.
GPS receivers are used in many ground-based applications, from large-scale industrial transport navigation systems to fitness trackers or smartphones. However, using GPS receivers in space is a much more challenging task compared to normal terrestrial use, as the cruising speed of satellite is about 8.000 m/s where on the ground we talk more on 50 to 100 m/s at best.
HIGH SHORT-TERM STABILITY & LOW PHASE NOISE
For GNSS function in a spacecraft, the short-term stability of the OCXO is the key parameter, in order to get a perfect absolute timing between 0 and 1 second (as the PPS signal is delivered from MEO orbit GNSS satellites).
OCXO can also be used for Ranging function, which consist in calculating the distance between objects in Space (measurement time of flight).
Integrating a high stability OCXO EWOS in GNSS Board, gives the possibility to maintain the time dimension in the system when GNSS is not available. Frequency of 10 MHz is traditionally used for GNSS function, looking at low phase noise close to the carrier (10Hz, 100 Hz offset).
(Telemetry, Command, Control)
Thanks to their trade-off between power & stability, EWOS™ play a major role in TTC radios. They are used to clock the RF ADC or DAC and also embedded FPGAs.
Other satellites RF functions using OCXOs
Syrlinks OCXO for space applications can also be used on a variety of on-board RF functions such as Tx/Rx antenna as frequency source with low phase noise floor before frequency synthesis/multiplication to GHz levels.