Furuno to introduce GF-100 Series GNSS disciplined oscillators with anti-jamming, anti-spoofing features

Furuno plans to launch its GF-100 Series of dual-band GNSS disciplined oscillators (GNSSDOs) in November 2026, adding new timing modules designed to improve resilience against GNSS interference in critical infrastructure applications.

The new lineup includes the GF-102, GF-103, GF-105S and GF-105G. According to Furuno, the modules are intended for equipment requiring precise timing, including telecommunications networks, radio base stations, PTP grandmaster clocks, broadcast systems, satellite communications terminals and electric power monitoring systems.

The GF-100 Series combines a dual-band GNSS receiver with a high-stability oscillator to provide accurate timing while maintaining synchronization during GNSS disruptions. The company said the modules are designed to address growing concerns over GNSS jamming and spoofing by automatically detecting signal anomalies and transitioning to holdover mode using the onboard oscillator.

Among the series’ key features are:

• Automatic transition to holdover mode when jamming or spoofing is detected.
• Dual-frequency L1/L5 GNSS reception, including independent L5 signal acquisition.
• Support for Galileo Open Service Navigation Message Authentication (OSNMA) and Japan’s Quasi-Zenith Satellite System Navigation Message Authentication (QZNMA) to help verify signal authenticity.
• Dynamic satellite selection to improve timing performance in challenging multipath environments.
• Time Receiver Autonomous Integrity Monitoring (T-RAIM), which continuously evaluates satellite reliability and excludes abnormal signals from timing calculations.
  Furuno said the modules will be available in two form factors. The compact GF-105S delivers the same ±1.5-microsecond-per-24-hour holdover performance previously available only in the larger GF-8805 module while reducing mounting area by about 80%. The new products also maintain hardware compatibility with the company’s existing GF-880x Series, allowing equipment manufacturers to upgrade existing designs more easily.

The company recommends pairing the modules with its AU-500 GNSS antenna, which features high noise immunity and an IP67 environmental rating.

Furuno said it has participated in the international Jammertest GNSS resilience event in Andøya, Norway, since 2024 and plans to evaluate the GF-100 Series during the 2026 event. The company said insights from those field tests contributed to the design of the new timing modules.