Product Spotlight: Endura Super-TCXO Advances PNT Resilience Against GNSS Attacks
Imagine a battalion navigating rugged terrain without a global navigation satellite system (GNSS) signal—it’s a situation that could last minutes or hours and can put troops at risk with navigation errors, system disruption, collisions and much more. The causes for outages can vary from harsh terrain and physical obstructions to signal jamming and spoofing from bad actors. It is during these outages that positioning, navigation and timing (PNT) systems must rely on local sensors until the GNSS signal is restored.
SiTime’s new Endura® super temperature compensated oscillator (Super-TCXO®), ENDR-TTT, for PNT is a lifeline for GNSS receivers to maintain accurate operation even when satellite signals are unavailable. Engineered to provide resilience against jamming and spoofing, this ultra-stable, low-power solution is ideal for mission-critical applications in aerospace, defense and industrial environments.
Accelerate GNSS Recovery
GNSS outages or interference can disrupt navigation systems. When timing uncertainty grows, PNT systems must scan a wider frequency range to reacquire GNSS signals—creating greater exposure to spoofing. Quartz-based oscillators lose accuracy quickly and often require additional engineering to handle shock, vibration and temperature extremes. In harsh environments, quartz timing errors can compound, leading to navigation deviations of hundreds of kilometers.
The ENDR-TTT delivers ruggedized performance out of the box, extending time holdover—the ability of a system to maintain accurate timing and positioning even when GNSS signals are lost. The ENDR-TTT eliminates risk with exceptional stability—providing up to 20x longer holdover and 20x greater navigational precision under extreme conditions. This ensures reliable performance when GNSS signals are unavailable.
“SiTime’s Endura Super-TCXO, ENDR-TTT, allows us to create a multi-layer anti-spoofing methodology,” said Paul McBurney, GNSS expert, CTO and co-founder at OneNav. “The first layer minimizes the search window, preventing spoofing because signals outside the window are never tracked. The second layer addresses exceptionally large search windows, such as in first acquisition, where spoofers can be tracked. In this case, the spoofer signals can be identified and removed due to SiTime’s ultra-stable reference clock.”
Key Advantages
- Ultra-Stable Holdover: When GNSS signals are unavailable, systems must rely on local timing. ENDR-TTT delivers exceptional stability, maintaining precise timing far longer than quartz-based oscillators. This ensures navigation accuracy even during extended GNSS outages.
- Spoofing Resilience: Timing uncertainty can widen the frequency search window during GNSS reacquisition, increasing exposure to spoofed signals. ENDR-TTT minimizes this risk by narrowing the resynchronization window, enabling faster recovery and reducing vulnerability to spoofing attacks.
- Ruggedized Performance: Harsh environments introduce shock, vibration and temperature extremes that degrade quartz oscillators. ENDR-TTT is engineered to exceed industry standards for environmental resilience, delivering consistent performance without additional design complexity.
- Low Power, Small Size: Aerospace and defense platforms often face strict size and power constraints. ENDR-TTT combines best-in-class stability with a compact footprint and low power consumption, making it ideal for mission-critical systems where efficiency matters.
Superior Resilience to Stay on Course
When GNSS signals fail, the Endura Super-TCXO for PNT keeps systems on course. “Our latest product delivers a powerful combination of superior performance, low power and small size, that leads the industry for PNT applications,” said Piyush Sevalia, executive vice president of marketing at SiTime. By combining ultra-stable holdover, spoofing resilience and ruggedized performance in a small, power-efficient package, the Endura Super-TCXO strengthens PNT systems for aerospace, defense and industrial applications. It’s the ultimate timing solution for contested environments—delivering resilience, precision and reliability when it matters most.
Learn more about the Endura Super-TCXO, ENDR-TTT, for PNT and how it ensures secure, accurate navigation—even when GNSS isn’t available.