LEO Satellite Communications

LEO satellites provide lower latency and higher bandwidth. To achieve this, they depend on ruggedized reference clocks for uplink/downlink comms and clocking the processor. These timing components must withstand high levels of vibration during launch and continued extreme temperature variations in orbit. If timing fails, receivers lose lock to satellites and navigation systems won’t receive critical data.
SiTime ruggedized Endura™ timing solutions are built to operate in harsh environments, overcoming the inherent weaknesses of quartz and delivering low failure rates, long-term reliability, and robust performance.
SiTime Ruggedized Endura MEMS Timing Benefits
Precision Timing50x better acceleration sensitivity ±0.5 ppm up to 105°C No activity dips |
Most Robust in Harsh Conditions20x better mechanical shock survivability 4x better vibration resistance Extended operating temperature range |
Higher ReliabilityConforms to MIL-PRF-55310 No quartz reliability issues No cover or shielding |
LEO Satellite Communications Block Diagram
Endura MEMS Timing Solutions for LEO Satcom
Devices | Key Features | Key Values |
---|---|---|
Super-TCXO
SiT5146 1 to 60 MHz
SiT5147 60 to 220 MHz
|
|
Reference clock for uplink/downlink comms |
Differential XO
SiT9346 1 to 220 MHz
SiT9347 220 to 725 MHz
|
|
DSP, FPGA & processor clocking |
LVCMOS XO
SiT2044 1 to 110 MHz
SiT2045 115 to 137 MHz
|
|
DSP, FPGA & processor clocking |
Endura Timing Outperforms Quartz
Best-in-Class-Aging |
Lower Acceleration (g) Sensitivity |
---|---|
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Endura Timing Outperforms Quartz
Acceleration Sensitivity

Mechanical Shock

Quality

Reliability MTBF (Million Hours)

Tested in Accordance with MIL Specifications
MIL-PRF-55310 | Test | Single-ended XO | Differential XO/VCXO/DCXO | TCXO |
---|---|---|---|---|
3.6.40.1 | Shock | ● | ● | ● |
4.8.18.3.1 | g-Sensitivity | ● | ● | ● |
3.6.34.1 | Frequency aging | ● | ● | ● |
3.6.17.1 | g-Sensitivity, constant acceleration | ● | ● | ● |
3.6.38.3 | Phase noise under vibration | ● | ● | ● |
3.6.10.2 | Frequency-temperature stability with hysteresis | ● | ● | ● |
3.6.45.2 | Ambient pressure | ● | ● | ● |
3.6.16.5 | Allan deviation | n/a | n/a | ● |
3.6.10.4 | Frequency-temperature stability with hysteresis and trim effect | n/a | ● | ● |
3.6.15 | Retrace | n/a | n/a | ● |
3.6.30.7 | Modulation frequency response | n/a | ● | ● |
3.6.41.1 | Acceleration survivability | ● | ● | ● |
3.6.7 | Frequency warm up | n/a | n/a | ● |
