Viavi Solutions Inc. has launched the patent-pending Cesium-less ePRTC360+ holdover solution to safeguard at-risk critical power grids, transportation, aviation and public safety systems, 5G mobile networks and AI data center infrastructure against the increased threat of GNSS timing disruptions. It is the only alternative to Cesium clocks to meet ITU-T G.8272.1 standards.
The international ITU-T G.8272.1 standard stipulates that Enhanced Primary Reference Time Clock (ePRTC) holdover must have short-term drift of less than 30 ns when entering into holdover and a long-term drift of less than 100 ns over 14 days, all traceable to UTC. Previously achieved only by Cesium atomic clocks, VIAVI’s ePRTC360+ now also meets this standard.
The ePRTC360+ has been successfully tested across a range of live-sky defense and commercial jamming/spoofing environments, and has been integrated into VIAVI’s SecurePNT 6200 product series. The technology can maintain 100 ns accuracy during GNSS-denied threats through the resilient altGNSS GEO-L service with no time limit.
It also combines an augmented VIAVI SecureTime GEO anti-jamming antenna and an enhanced GNSS anti-spoofing antenna that also receive eGNSS GEO service with GPS/GNSS-NMA authentication for spoofing detection and mitigation.
Unlike conventional GNSS omni-directional signals, which can be drowned out by low-power interference, VIAVI’s GNSS-independent GEO-L service leverages encrypted and highly directional L-band signals transmitted from geostationary satellites. Coupled with the augmented VIAVI SecureTime GEO antenna, the altGNSS GEO-L service provides enhanced anti-jamming protection and a resilient timing reference for the ePRTC360+’s internal Rubidium holdover oscillator and enables smooth multi-orbit source switchover, even when primary GNSS frequencies are jammed, spoofed or subject to sophisticated meaconing attacks.
The affordability of ePRTC360+ clocks compared to Cesium clocks enable operators to deploy them beyond the core and across the network. They also complement non-RF Cesium clocks at the core. This boosts end-to-end sync network robustness and holdover reliability through meshed network PTP feeds as backup between the clocks, especially in case of local or regional jamming and/or spoofing threats.
In addition, the ePRTC360+ addresses constraints posed by the use of Cesium clocks for holdover timing. These include sensitivity to shock, delicate and multi-stage startup procedures that take days to complete, the need for ECCN 3A001.i licenses for export, long GNSS learning period of up to 40 days, as well as strict shipping and storage protocols. In addition, Cesium tubes need to be replaced approximately every seven years, and the dismantling and disposal of Cesium clocks are classified as a hazard due to their material content.
The ePRTC360+ eliminates these hurdles and has been designed for rapid and easy integration into any vendor’s grandmaster clock system. It enables operators to meet stringent ePRTC requirements while reducing total cost of ownership.
The ePRTC360+ will be demonstrated at VIAVI’s Stand 5B18 at Mobile World Congress (MWC) Barcelona 2026, March 2-5, in Barcelona, Spain.
Dedicated research and development, funded by European Union (EU) and European Space Agency (ESA) programs over the years, has played a key role in Galileo Second Generation.
Among the innovations that will benefit the new satellites are the development of new atomic clocks, links that allow the satellites to “talk” to one another in orbit and a prototype ground station that can precisely pinpoint satellites in the sky. These advanced technologies will ensure Galileo continues to provide world‑class positioning, navigation and timing to users worldwide.
The importance of R&D
Satellite navigation is constantly evolving, with new technologies being deployed. But before a technology can fly on a satellite, it must be derisked and qualified. This is where research and development (R&D) comes in, laying the groundwork for new technologies long before they see the light of day.
Horizon 2020 and Horizon Europe are R&D programs funded by the EU. A significant budget from these programmes is delegated to ESA for R&D to derisk new technologies for evolutions of Europe’s Galileo and EGNOS systems.
Complementing these EU R&D programs, ESA programs such as the General Studies Programme (now Discovery and Preparation), General Support Technology Programme and the former European GNSS Evolution Program (EGEP) have also performed R&D for future satellite navigation technologies.
R&D spurs the innovation that allows Galileo and EGNOS to modernise and develop new applications and services. Several activities funded through these programmes have contributed to Galileo Second Generation (G2). Some of these technologies will already fly on the G2 satellites when they are launched in the coming years.
New ways of keeping time
Galileo relies on highly precise onboard atomic clocks to ensure accurate global positioning and timing. Here, an iodine optical clock by SpaceTech, Germany (Credit: ESA)
Galileo delivers world-class positioning and timing, and its onboard clocks are the key to its performance. Each first generation Galileo satellite carries two passive hydrogen maser and two rubidium atomic frequency standard clocks. These clocks, developed by Leonardo and Safran Timing Technologies, respectively, are currently Galileo’s only space-qualified clocks.
A rubidium pulsed optically pumped (Rb POP) clock by Leonardo, Italy. (Credit: ESA)
To keep up with the latest technologies and allow for a broader diversity of European qualified clocks, R&D activities have encouraged European companies to develop new types of space-worthy atomic clocks. This investment is critical due to the time and expertise it takes to develop such complex and sensitive technologies. These activities aimed to develop alternative atomic clocks for Galileo that can improve performance and robustness and support Europe’s place as a leader in satellite navigation.
A Mercury ion clock (MIC) from Safran Timing Technologies, Switzerland. (Credit: ESA)
Seven innovative clock technologies were developed by European companies from France, Germany, Italy and Switzerland. After initial development activities, three of these clocks — proposed by Leondardo, SpaceTech and Safran Timing Technologies — were selected to progress to hardware development in preparation for a first flight.
Leonardo’s Rubidium Pulsed Optically Pumped clock is currently under development and planned to fly as an experimental clock on a Galileo Second Generation satellite. The Iodine Optical clock developed by SpaceTech is undergoing early development and shows potential for future use as an experimental clock on Galileo satellites. The Mercury Ion clock by Safran Timing Technologies recently launched its development activities.
Following an analysis of the clocks’ eventual in-orbit performance, a programme decision by the European Commission will be made before starting the operational phase of these new clock technologies.
Conversations in the sky
An intersatellite link transceiver by Thales Alenia Space. (Credit: ESA)
The Galileo system currently relies on links between satellites and ground stations to monitor and control the satellites and to determine the onboard clock skew. Clock skew occurs when a clock signal reaches different parts of a system at different times, which can cause errors in position calculations.
Galileo Second Generation will introduce inter-satellite links (ISL), allowing the satellites to ‘talk’ directly to one another in orbit. This will enable additional time synchronisation and ranging measurements that will improve knowledge of the satellites’ orbit and clock skew.
ISL will also allow faster data dissemination. If a particular satellite is not visible to a ground station, information can be sent to a different satellite and then passed on instead of waiting for the satellite to be visible.
An intersatellite link transceiver by Airbus Defence and Space. (Credit: ESA)
Two early models of ISL transceivers that are essentially identical to those which will fly on the Galileo Second Generation satellites were designed and developed. The transceivers, which can both send and receive signals, were developed by Thales Alenia Space (Spain) and Airbus Defence and Space (Germany).
One of these transceivers is about to enter the formal testing phase, while the other has undergone successful environmental qualifications. After the transceivers have completed their qualifications and testing, they will be ready for their trip to space.
Precisely pinpointing satellites
Accurate positioning, navigation and timing relies on knowing precisely where satellites are in their orbits. Galileo satellites are located by tracking their L-band antenna transmissions from the ground. Each satellite also has a laser retroreflector, which allows measurement of their orbit to within a few centimeters. Known as satellite laser ranging (SLR), this method measures the time it takes for a laser pulse to make the trip from a ground station, called an SLR station, to the satellite and back, then uses these measurements to determine the satellite’s orbit. Presently, SLR stations are owned and operated by scientific community users and serve multiple space missions.
One of the challenges of current SLR is the fact that the lasers are not safe for human eyes and cannot be used if an aircraft is flying nearby as the lasers could blind the pilots. This means SLR stations must coordinate with civil aviation and may not be allowed to use all parts of the sky. SLR stations also have limited availability due to local atmospheric conditions (clear skies are key), and low levels of automation (intensive need for human operators).
A prototype satellite laser ranging station in Matera, Italy. (Credit: ESA)
To mitigate these limitations, a modernized, eye-safe SLR station prototype for Galileo satellites has been developed by DiGOS (Germany) and commissioned in Matera, Italy. Due to the station design and laser wavelength used, there will be no need to coordinate with civil aviation. The station’s new technologies also explore increased automation using a predefined schedule to reach satellites. Although human operators are still needed, their workload is reduced.
A field campaign of the prototype SLR station is planned for this year as part of the Galileo Second Generation System Test Bed tasks. It will evaluate the potential benefits of SLR as a complement to L-band ground ranging. If the station is added to the Galileo ground segment, it could enhance the system’s robustness by providing an independent means of determining the satellites’ locations. In this case, interface design adjustments would need to be made to allow operational use of the station.
Beyond providing another method for determining Galileo satellite orbits, this station could also help contribute to the Galileo Terrestrial Reference Frame and could support ESA navigation scientific missions such as Genesis.
Micro-Magic has released the U4930 series, a reliable and cost-effective six-axis MEMS inertial measurement module that can be widely used in navigation, control and measurement fields for vehicles, ships and drones.
Typical applications include vehicle/ship attitude measurement, UAV attitude reference and trajectory control, mobile mapping, track inspection, underwater high-precision navigation, and Satcom-on-the-Move.
The U4930 series integrates high-performance MEMS gyroscopes and MEMS accelerometers within an independent structure. The three-axis MEMS gyroscopes sense the angular motion of the carrier, and the three-axis MEMS accelerometers sense the linear acceleration of the carrier.
The system internally performs compensation for zero bias, scale factor, non-orthogonal error, and acceleration-related terms across all temperature parameters, maintaining high measurement accuracy over a long period of time.
The module supports custom communication protocols and provides synchronization for GPS/GNSS time data and pulse per second (PPS) signals.
The U4930A series inertial measurement module can be configured with various hardware and software to meet user needs.
Project establishes innovative test framework to help UK operators, providers and suppliers adopt best practice and benchmark success
Spirent Communications, now part of Keysight Technologies, has partnered with the European Space Agency (ESA) to lead an initiative aimed at increasing the resilience of positioning, navigation and timing (PNT) systems used in critical national infrastructure. Under the initiative, Spirent and partners will deliver a comprehensive test framework to drive measurable resilience in PNT systems for users, operators and providers of critical infrastructure in the United Kingdom.
Supported by Element 2 of ESA’s Navigation Innovation and Support Program (NAVISP), the initiative is designed to raise awareness and improve resilient PNT test and assessment by providing a pathway to assess, validate and rate PNT equipment and services used in critical national infrastructure. The 2023 UK government report The Economic Impact on the UK of a Disruption to GNSS estimates a seven-day GNSS outage could cost the UK economy £7.6 billion. Critical infrastructure is heavily dependent on satellite-based PNT systems and data.
“For years, organizations have been wrestling with a fundamental challenge: they know PNT resilience matters, but they do not have a clear way to measure it or benchmark their progress,” explained Mark Holbrow, vice president of Engineering and Product Development at Spirent Positioning. “This new initiative changes that by building the tools and frameworks that let critical national infrastructure operators quantify resilience, track it, and improve it over time, and we’re proud that ESA has entrusted Spirent to lead this exciting three-year project.”
The Resiliency in Critical National Infrastructure will support the UK government’s resilient PNT strategy by enabling access to rigorous, quantitative test evidence and operational insights that help evaluate and validate PNT systems across essential sectors. It will comprise three core components:
Spirent PNT Alliance brings together companies, academic research partners, and PNT professional and government bodies to identify, develop and cater resilience services for critical infrastructure. It will include the Royal Institute of Navigation and other strategic partners to complement their activities and help build a resilient PNT ecosystem in the UK by commercializing best practices and connecting infrastructure operators with new technologies and test approaches.
PNT Shopfront showcases solutions that aid the adoption of resilient PNT and help to assure regulatory compliance for critical PNT dependencies.
PNT Resiliency Health Check will enable independent appraisal of GNSS equipment capability against general performance, resilience and security criteria. Annual health check assessments will help organizations understand their dependencies, identify vulnerabilities, and track improvements over time, with a technical framework that scores resilience against standard benchmarks to create a pathway toward industry-wide test methodologies.
“Intentional and malicious disruptions to GNSS are now a daily occurrence, and are pervasive in the aviation and maritime sector,” said Ramsey Faragher, director of the institute. “The Royal Institute of Navigation is focused on raising awareness to these issues and in promoting the needs for improved resilience against such disruptions, especially within Critical National Infrastructure. Our Best Practice Guidelines emphasize the criticality of thorough testing in order to verify resilience and to help protect against both existing and future attack vectors. The UK is well placed to take a lead in this area, and well placed to inspire other nations to follow suit. We are really pleased to see initiatives like these from our corporate partners, and we look forward to supporting them.”
Furuno will begin providing new firmware for its GNSS receivers for time synchronization, including models GT-100, GT-90 and GT-9001, which adds authentication features (OSNMA/QZNMA) and significantly strengthens anti-jamming and anti-spoofing measures.
In fields that support critical infrastructure such as telecommunications, finance and power, GNSS vulnerabilities have become a major issue. The Furuno team participated in Jammertest 2025, the world’s largest GNSS resilience testing event. Jammertest 2025 took place in Norway, and verified robustness and reliability under real attack conditions to meet the requirements of critical infrastructure.
Features of the new firmware
The GT-100, GT-9001 and GT-90 modules. (Photo: Furuno)
Addition of authentication functions (OSNMA/QZNMA): Authentication messages from Galileo (European GNSS) and QZSS (Japan’s Quasi-Zenith Satellite System) confirm the authenticity of navigation messages, strengthening resistance to spoofing attacks.
Enhanced anti-jamming and anti-spoofing measures: Detect and eliminate various interference signals with high precision, ensuring stable time synchronization.
Removal of altitude restrictions, enabling use in the stratosphere and similar environments
Addition of TAI (International Atomic Time) output function
Support for multiple data formats (RTCM10403.3, RINEX4.1, binary)
Availability For existing users: Provided as a firmware update.
For new shipments: GT-100, GT-90 and GT-9001 with the new firmware are scheduled to ship beginning in March 2026.
Related product information Furuno has also launched the GNSS Surge Protector, TVA-05V for GNSS antennas. This product protects GNSS receivers from surges caused by lightning, further enhancing the stable operation of critical infrastructure.
In Jammertest 2024, challenges were identified using GT-100; in Jammertest 2025, improvements were validated with the upgraded version, confirming the effectiveness of the resilience algorithms under operational conditions.
Hoptroff, a precision timing specialist, has partnered with the London Stock Exchange (LSEG) through its Hosting & Connectivity Partner Platform, which enables financial markets customers to access third-party applications and services via LSEG’s global connectivity services.
The move reflects a fundamental shift in how financial services views timing infrastructure. No longer just a technical requirement, time has become a strategic investment in cybersecurity and digital resilience.
Timing precision has long been a regulatory necessity in financial markets. Rules such as MiFID II and FINRA CAT NMS define exactly how accurate trade timestamps must be. What’s changing is the expectation that timing infrastructure itself be resilient and independently verified.
Emerging EU and US guidelines now urge firms to mitigate over-reliance on GNSS/GPS and to implement terrestrial, traceable time sources that are protected against jamming, spoofing and cyberattacks. Time is under threat, and for financial institutions, dependable time is now a core element of regulatory resilience and audit confidence.
“Partnering with LSEG is significant,” said Tim Richards, CEO of Hoptroff. “As one of the world’s most influential financial institutions, their recognition of Hoptroff’s timing solutions demonstrates the strategic importance of resilient time that is easily accessible.”
Hoptroff combines precision timing with the reliability and uptime the sector demands, then pairs it with software that makes compliance straightforward. “Everything is plug-and-play, so firms get instant access without heavy upfront infrastructure costs,” Richards said.
Hoptroff addresses both established and emerging regulatory requirements for time synchronisation. The company holds ISO 27001 and ISO 9001 certifications and exceeds the precision standards financial markets require, offering accuracy across a terrestrial network that connects directly to national timing authorities, including NIST, NPL and RISE. This allows firms to meet global financial services regulations, such as MiFID II, FINRA CAT, and the EU Digital Operational Resilience Act (DORA), without sacrificing trading accuracy or uptime.
Endura Super-TCXO Delivers Superior Holdover and Ruggedized Performance for Aerospace, Defense and Industrial Applications
SiTime Corporation has launched the Endura temperature-compensated oscillator (Super-TCXO), ENDR-TTT, for position, navigation and timing (PNT) applications. Engineered for superior holdover — uninterrupted operation when GNSS is not available — and resistance to jamming and spoofing, ENDR-TTT is an ultra-stable, low-power product for GNSS receivers in aerospace, defense and industrial markets.
“SiTime’s Endura Super-TCXO, ENDR-TTT, allows us to create a multi-layer anti-spoofing methodology,” said Paul McBurney, GPS World Editorial Advisory Board member, 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.”
When GNSS signals are dropped because of unavailability or degradation — including signal jamming or extreme environmental conditions — holdover maintains timing stability locally to enable uninterrupted network operation. The ENDR-TTT Endura Super-TCXO provides up to 20x longer holdover and 20x better PNT accuracy, dramatically improving spoofing resistance.
“SiTime’s ENDR-TTT Endura Super-TCXO accelerates GNSS recovery by narrowing the resynchronization window, reducing spoofing and setting a new standard for ruggedized precision timing,” said Piyush Sevalia, executive vice president of marketing at SiTime. “Our latest product delivers a powerful combination of superior performance, low power and small size, that leads the industry for PNT applications.”
Additional features for SiTime ENDR-TTT Endura Super-TCXO include:
±50 ppb stability over temperature (FvT); up to 10x better frequency stability over temperature versus quartz alternatives.
-55ºC to +125ºC operating temperature range.
30,000 g operational shock; up to 20x better resistance to shock.
0.004 ppb/g typical g-sensitivity; up to 50x better than quartz alternatives.
±0.5 ppm 20-year aging—eliminates field recalibration.
Optional I2C/SPI digital pulling capability for system frequency fine-tuning.
SiTime’s ENDR-TTT is sampling now. Mass production is expected in the first quarter of 2026.
Siemens has unveiled its latest innovation for energy infrastructure: the Siprotec 5 Precision Time Protocol (PTP) Grandmaster Clocks (GMC).
Built to secure the backbone of modern power grids, the GMC ensures resilient, fail-safe time synchronization for digital substations, safeguarding critical protection functions from disruption, shielding against external disturbances, and strengthening cybersecurity to boost overall grid reliability.
Avoiding GNSS disruptions. Conventional digital substation architectures often rely on redundant GNSS-based grandmaster clocks. However, even with redundancy, they remain vulnerable: disturbances to GNSS signals, whether from natural phenomena like solar storms or intentional interference such as jamming and spoofing, can cause disruptive “‘jumps” in the time base. Such disruptions force merging units to resynchronize, temporarily disabling critical protection functions and can lead to unnecessary removal of equipment from service or even cause false tripping events, impacting grid stability and increasing operational costs. Siemens’ new solution mitigates these risks, ensuring uninterrupted, secure operation.
Siemens’ solution separates sample synchronization from global time synchronization using specialized internal time sources. The Siprotec 5 devices, equipped with integrated PTP Grandmaster Clocks compliant with IEEE 1588v2/PTP standard, operate independently from external GNSS signals, using internal oscillators as time references for precise synchronization.
Changeover technology. A key feature of this approach is Siemens’ patent-pending Seamless PTP grandmaster changeover technology, built into Siprotec 5 devices. This ensures that when primary clocks return, they first align with active backup clocks before resuming their role. In doing so, disruptive time base jumps during switchovers are prevented, keeping protection functions continuously available.
The specialized synchronization enables process bus networks in digital switchgears to operate autonomously without external access points, significantly strengthening cybersecurity by isolating the process bus from the station bus network.
VIAVI Solutions has received an award from the U.S. Department of Transportation (DOT) through its Complementary Positioning, Navigation and Timing (CPNT) Action Plan Rapid Phase II.
VIAVI will integrate and test its SecureTime altGNSS GEO-L service and SecurePNT 6200 resilient timing solution at the VIAVI Automated Lab-as-a-Service for Open RAN (VALOR) and the Open RAN Center for Integration and Deployment labs. VALOR and ORCID are funded by the National Telecommunications and Information Administration Public Wireless Supply Chain Innovation Fund.
Incidents of GNSS signal interference, such as jamming and spoofing, have increased significantly in recent years, emphasizing the need for a resilient PNT ecosystem that can function in denied, degraded and disrupted space operational environments (D3SOE). Complementary to GPS and GNSS, VIAVI’s SecureTime GEO-L service and SecurePNT-6260 switch to a completely GPS-independent, GEO-L satellite-based time service and a precision holdover clock in the event of jamming or spoofing with no interruption perceived by the critical infrastructure system.
The DOT action plan aims to test systems that augment or replace GPS and GNSS, providing accurate timing services to critical infrastructure ranging from data centers and financial systems to power grids and cellular networks. Data from the VALOR, ORCID and field trials will be used to support widespread adoption of complementary positioning, navigation and timing services to protect the nation’s critical infrastructure.
“Integration and testing at the VALOR and ORCID labs demonstrate the technology’s readiness in an operational critical infrastructure environment. We look forward to partnering with DOT and NTIA to improve resilience for critical infrastructure and providing vital data to support widespread CPNT adoption,” said Doug Russell, senior vice president and general manager of aerospace and defense at VIAVI.
In addition to integration and testing at the VALOR and ORCID labs, the VIAVI GEO-L service and user equipment will be tested at an upcoming government field test event that provides live-sky jamming and spoofing of GPS/GNSS.
Adtran‘s Oscilloquartz synchronization platforms now support Galileo’s Open Service Navigation Message Authentication (OSNMA). OSNMA is a GNSS authentication service designed for civilian use.
By verifying that timing data originates from genuine Galileo satellites, OSNMA ensures authenticity and integrity at the point of reception. The new feature, available via firmware update for supported multi-band GNSS receivers, adds an extra layer of protection against spoofing and manipulation, empowering existing deployments to strengthen security without hardware changes or service disruption.
OSNMA support from Adtran brings a new level of GNSS security to critical infrastructure. Available for multi-band GNSS receivers in the OSA 5412, OSA 5422, OSA 5430 and OSA 5440 product lines, the feature integrates with Galileo’s Open Service, using digital signatures and TESLA chain keys to authenticate navigation data. This ensures that timing and positioning information is verified as authentic and protected against spoofing or manipulation.
Adtran’s Oscilloquartz Syncjack probing adds a second layer of defense, detecting record-and-replay attacks – also known as meaconing – by comparing GNSS signals against trusted PTP sources. This dual-layer approach helps identify subtle timing manipulations and delay attacks that traditional receivers may miss.
“From 5G and smart power grids to financial networks and data centers, bringing authentication to GNSS is a game changer for critical infrastructure,” said Gil Biran, GM of Oscilloquartz, Adtran. “By enabling our customers to defend against sophisticated threats, including meaconing, we’re helping them achieve greater timing integrity for their networks. Existing customers can access this new GNSS security feature with a simple firmware update, helping them stay protected as threats continue to evolve.”
Net Insight has launched TN3100E, a TimeNode in the Zyntai family built for markets that demand enhanced timing resilience in challenging environments. The TN3100E delivers multiband GNSS for superior accuracy, supports India’s GNSS IRNSS/NavIC, and adds advanced anti-jamming and anti-spoofing features.
The TN3100E is the latest TimeNode hardware unit in the Zyntai product family. It provides enhanced GNSS functionalities designed for markets that depend on GNSS as time source in challenging environments where robust protection against interference is essential.
The TN3100E introduces new capabilities for Improved anti-jamming and anti-spoofing. TN3100E fully supports the Open Service Navigation Message Authentication (OSNMA) used by Galileo to verify signal authenticity. This, together with Net Insight’s time-based anti-spoofing techniques, enables the TN3100E to deliver a high level of anti-spoofing protection.
TN3100E is commercially available now. Visit Net Insight’s booth 24 at ITSF 2025 Oct. 27–30 in Prague.
Microchip Technology has released the TimeProvider 4500 v3 grandmaster clock (TP4500) designed to deliver sub-nanosecond accuracy for time distribution across 800 km long-haul optical transmission.
Most current deployments require GNSS at grandmaster sites, but the TP4500 enables highly resilient synchronization without relying on GNSS, providing critical infrastructure operators with complementary positioning, navigation and timing (PNT). The TP4500 is a resilient, terrestrial solution for the absence of GNSS in precise timing, alleviating physical obstruction, security and signal interference costs associated with GNSS-dependent deployments.
The TP4500 supports time reference provided by UTC(k) UTC time provided by national labs. It offers a premium capability that delivers High Accuracy Time Transfer (HA-TT) as defined by ITU-T G.8271.1/Y.1366.1 (01/2024) to meet 5 nanoseconds (ns) time delay over 800 km (equating to 500 picoseconds (ps) average per node, assuming 10 nodes), setting a new industry benchmark for accuracy.
The TP4500 system can be configured with multiple operation modes to form an end-to-end architecture known as virtual PRTC (vPRTC), capable of delivering PRTC accuracy over a long-distance optical network. vPRTC is a carrier-grade architecture for terrestrial distribution of HA-TT, which has been widely deployed in operator networks throughout the world.
TimeProvider 4500 v3 is a key steppingstone towards support of the ITU-T G.8272.2 standard, which defines a coherent network reference time clock (cnPRTC) in amendment 2 (2024). An cnPRTC architecture ensures highly accurate, resilient, and robust timekeeping throughout a telecom network. This allows stable, network-wide ePRTC time accuracy, even during periods of regional or network-wide GNSS unavailability or other failures and interruptions.
