Making waves at Long Beach with the OSA 5405-S

Our STL-powered grandmaster clock is big news for resilient, precise timing, and it certainly stole the show at PTTI/ION.
Daniel Burch
Long beach at night

Sunny Long Beach in California was once again the setting for the Precise Time and Time Interval (PTTI) conference. Organized by the Institute of Navigation (ION), the annual meeting gathers engineers, technicians, companies and managers to discuss all things timing and synchronization. 

As always, the Oscilloquartz team was there, and this year we had something a special up our sleeve, or rather in our pocket: our OSA 5405-S dual GNSS/LEO grandmaster clock, a hockey puck-sized solution that provides incredibly precise and robust satellite timing – even indoors.

Though we weren’t doing an official demo, the OSA 5405-S nevertheless ended up taking the conference by storm. And why wouldn’t it? Developed with our partner, Satelles, it’s the first grandmaster on the market capable of leveraging Satellite Time and Location (STL) data from low Earth orbit (LEO) satellites. 

We walked the device around the conference floor for the entire afternoon, and it never once skipped a beat, remaining locked to Satelles’ LEO satellites, faithfully delivering timing signals. Even our competitors had to admit they were impressed!


But what’s the value of STL? Isn’t the Global Navigation Satellite System (GNSS) the gold standard when it comes to satellite timing traceable to coordinated universal time (UTC)? Well, not really. Though GNSS is commonly used as a cost-free source of highly accurate timing, it has an Achilles heel: signals are weak and also highly vulnerable to attack. Consider the fact that anyone can get hold of cheap, off-the-shelf components to jam or spoof GNSS signals — not exactly reassuring.

What’s more, because you also need a clear line of sight to receive GNSS signals, if you want to keep your receiver indoors, you must deploy an outdoor antenna and run cables into your building. Our OSA 5405-S with its 5400 STL module, however, is much easier to deploy because it leverages LEO satellites — part of the Iridium constellation of satellites — to receive STL data. LEO signals are around 1,000 times stronger than those generated by GNSS, so they perform well in most indoor environments without the need for roof-mounted antennas. The unit needs just one small antenna to provide Stratum-class timing and doesn’t just act as a grandmaster clock, it can also serve as a boundary clock and an edge client clock. And don’t forget that the OSA 5405-S is still a GNSS receiver.

OSA 5405 S

Key characteristics of STL-based timing

  • Strong signal: LEO-derived STL signals can be leveraged in environments where GNSS signals are weak or unavailable
  • Enhanced security: STL signals from LEO satellites are encrypted, making them more secure and resistant to spoofing and jamming attacks
  • Global availability: The Iridium constellation provides worldwide coverage, ensuring STL services are available anywhere on Earth

A critical building block to small cell connectivity

The 5405-S has multiple input types and outputs, including PTP, SyncE, NTP, 1PPS, 10MHz, ToD, and IRIG, with both electrical and optical ETH ports, meaning it has applications in data centers, power grids, 5G networks, and more. Just consider for a moment how difficult it is to synchronize 5G small cells at the bottom of a skyscraper-lined urban canyon using GNSS with all its fallibilities. Because the 5405-S leverages the higher signal strength of LEO satellites, the device can still deliver the strict synchronization needed. It’s this incredible versatility that has first adopters lining up to order units.

Our OSA 5405-S is set to become a key component of timing infrastructure as 5G networks continue to expand and the need for more resilient synchronization gathers pace globally. Quite deservedly, our compact and feature-packed device got an incredible reception at this year’s PTTI conference – pun very much intended. That’s because service providers and operators of critical infrastructure understand the threats to GNSS accuracy and often, they need to consider alternative options. The arrival of our 5405-S is as timely as it is welcome. It’s a triumph born of collaboration that will help render networks more resilient and more secure well into the future. 

For more info, check out our press release on the OSA 5405-S, as well as the OSA 5400 SyncModule™, an M.2 form factor STL/GNSS module that enables third-party equipment vendors to enhance synchronization in challenging environments.

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