The Road to
Interoperability

Breaking Down the Argument for RF over Fiber

6/17/2025

As you may have guessed, I’m pretty bullish about the role that RF over IP (RFoIP) will play in the digitalization of the space industry. RFoIP, along with an interoperable standard such as DIFI, enables flexibility, performance and dynamic operations that aren’t possible with the legacy options of analog signal transport over coax and RF over Fiber (RFoF). While those options have value for specific use cases, they are both limited by the need for dedicated coax/dark fiber connectivity and suffer performance degradation over long distances.

I’m confident enough in my belief that DIFI is the path forward for the satellite industry that I’m willing to play devil’s advocate and address some concerns raised about RFoIP. In no particular order, here are the most recent concerns I have seen, followed by my comments.

Concern 1: Many regions lack the IP network capacity to transport wideband signals and gateway traffic using RFoIP

This is probably the biggest knock on RFoIP, and rightfully so. RFoIP does require a significant amount of IP bandwidth—a single MHz of RF bandwidth can require up to 20Mbps of IP bandwidth. However, the largest satcom signals in commercial use today are 500Mhz in bandwidth and they can be comfortably transported on a standard 10Gbps IP network. For larger signals that are planned for the near future and for gateway applications, 40Gbps and 100Gbps IP networks and networking equipment are widely available today in all parts of the world at reasonable costs. Even the 5Ghz of spectrum that is available from full-use Q/V band will fit within a 100Gbps IP network. I saw one company argue that you should not use RFoIP because it can’t handle 6GHz bandwidth signals. I’m not sure where there is 6GHz of continuous spectrum available for satcom use today, let alone a contiguous 6GHz signal being transmitted. However, if this is a problem that you face today, I’m willing to concede that RFoF or analog transport over coax may be the most effective solution in this extreme case.

Concern 2: RFoIP solutions suffer substantial latency, which affects system performance

In some cases, RFoIP can add incremental latency to the overall satellite link performance—primarily from the IP network itself. However, other than some niche use cases such as high-speed trading or perhaps competition-level first-person shooter video gaming, the latency impact of RFoIP is insignificant when compared to the overall latency of the link and that of traditional analog or RFoF. What is important for many applications is the need for consistent latency, which can be tightly controlled within an RFoIP network.

Concern 3: IP networks are inherently insecure

Implying that analog networks are the more secure option is disingenuous. Specialized low volume analog or RFoF equipment software and firmware tend not to be regularly updated, which puts them at higher risk of hacking than their digital standard IT networking counterparts. Hackers have time to attack and find vulnerabilities in these static systems that they can exploit at will (just ask Viasat). Standard IT network equipment, on the other hand, follows industry best practices in cybersecurity procedures with regular updating and maintaining of the software and operating systems, which is critical regardless of whether it’s in the analog or digital realm.

Concern 4: Replacing existing infrastructure and teleport hardware to implement RFoIP is costly

This is a fair point, but also true of other transport options. Usually, new transport capabilities are only introduced with new satellites and/or bandwidth needs. For most new services/applications, RFoIP is the most cost-effective and future-proof option. However, if you’re considering a very large new bandwidth use case that 1) is just a single point to a single point, without redundant paths; 2) has no requirements for dynamic operations or switching; 3) already has dark fiber or coax available and installed for use; and 4) the transport distance is limited, then RFoF or analog RF transport might be the better solution. But without those conditions, it is hard to beat RFoIP.

At the end of the day, RF over IP delivers the network resiliency, flexibility and security that the satellite world needs to fully embrace to enable next-generation capabilities.

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Why Space is a Missing Piece in the 5G Puzzle

5/20/2025

I wouldn’t have expected an opening keynote at the telecom industry’s largest event to discuss the shortcomings of 5G—yet that’s exactly what happened at Mobile World Congress earlier this year, and by no less than one of the top executives of a major mobile industry association.

Mats Granryd, the now-former director general of GSMA, openly acknowledged that the industry hasn’t yet seen economic benefit from 5G adoption, identifying standalone 5G and the enterprise services it enables as the solution.

However, the advanced capabilities enabled by 5G SA, such as network slicing and enhanced mobile broadband, can only deliver value to an enterprise if it can reach that enterprise, and terrestrial networks are not ubiquitous. Satellite is a key missing piece of the 5G puzzle.

Release 17 of the 3GPP 5G standard defines protocols for integrating non-terrestrial networks (NTNs) into the 5G communications fabric, paving the way for a global, heterogenous 5G network that can deliver lucrative digital services—such as autonomous operations, digital twins and real-time performance monitoring—to any enterprise, anywhere.

Next-generation software-defined satellites are designed to be cell towers in space, with beams that can be shaped and steered on demand, enabling bandwidth to be delivered when and where it’s needed and adjusted to meet specific service requirements. A 5G NTN ground system provides back-end processing for the cell tower, routing traffic from satellites in orbit to the 5G core network to support the seamless delivery of digital services to any location.

The split between what is done on the satellite and what is done on the ground is based on the orbit and the network design. When combined, they provide the missing piece of the 5G monetization puzzle.

Partnering with satellite operators that have invested in next-generation space and ground assets—including a standards-based ground system that is purpose-built with the flexibility and scalability needed to support 5G services—opens the door for terrestrial operators to broaden their enterprise reach and start seeing a real return on their 5G investments.

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One-to-Many-to-Even More, Chasing an ESA Standard

4/22/2025

DIFI’s recently formed Electronically Steerable Antennas (ESA) Working Group is just getting started, but members are already making great progress on Stage One of their effort, accounting for the variety of use cases and network environments that need to be covered. It’s a complex problem; you could say a one-to-many problem.

Across consumer services, enterprise apps and defense readiness, the applications for ESAs are compelling, including some of today’s most-discussed needs such as mobility, multi-orbit and multi-mission support.

That “multi” nature is the biggest complicating factor, though not the only one.

ESAs represent a tremendous leap forward in dynamic functionality over traditional parabolics, which are designed to perform one function in static environments. That’s why the first step to expanding the existing Monitor and Control (M&C) standards to support ESAs is to determine how many unique uses in how many unique environments are needed to support how many types of users.

For example, the simplest type of use case would be enabling the traditional kind of connectivity used with parabolic antennas; that is, one modem endpoint to one antenna endpoint. Even here, a well-defined use case in the existing standards for parabolics, there are some unique aspects to ESAs that must be considered to get the full value of the ESA’s capabilities.

From there, use cases fall into at least five more “types,” starting with many modem endpoints to one antenna endpoint. This is the beginning solution for the much sought-after multi-orbit scenario. But it’s not the most advanced multi orbit scenario since it would not allow simultaneous multi-orbit connectivity. Doing that requires a different model: many dynamic modem endpoints connected to many dynamic antenna endpoints. In addition to simultaneous GEO/MEO/LEO connectivity, that scenario provides the resiliency expected for military operations.

Start adding mobility support into the equation and new factors arise. For example, what happens when your car enters a tunnel? Aero and maritime mobility bring similar unique factors.

A lot of very smart people are working on these issues for their own products and solutions; however, to achieve the kind of service we have come to rely upon from our smart phones—not to mention their ubiquity—will require industry standards implemented across antennas, modems and even M&C systems. The ESA Working Group includes many of those smart people from organizations across the supply chain to solve this problem at scale, from antenna makers to satellite operators to government end users. To join the effort, visit https://dificonsortium.org/join-now/

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It’s Official, Verified DIFI Compliance

3/25/2025

We were extremely excited to announce last week the two very first ground system products to be recognized as DIFI standard compliant.

This is a major milestone for DIFI that will bring confidence to ground system operators that they can rely upon a given product from a given vendor to meet or exceed functional interoperability expectations matching the standard.

Sometimes standards efforts get undermined because vendors will meet the heart of a standard but make adjustments to the “standard standard” for proprietary benefit but compromising interoperability. To a degree that happened in our own industry with VITA 49 and DVB-S2X over the years. One of our first tasks in moving forward with the DIFI standard was to anchor around a single, stable, accepted form of VITA 49 to build upon.

The first two compliant products, one from Keysight and one from Kratos, went through a manual version of the first type for our projected common process that will stipulate to “types” of compliance. The first type—silver—is based on self-testing, the second phase—gold—will involve third party validation. We are still defining and enabling the gold process, addressing elements such as approved certifiers, cost structures, etc.

Because the first two products were our “test case” milestone, we used a manual process with members of the DIFI Compliance Working Group validating the self-testing results. We’ll use the same manual model for the next six products that are already in the queue for verification. Ultimately, vendors will be able to choose between the silver and gold types that best meet their customers’ requirements.

I want to give a shout out to the members of the DIFI Certification Working Group, including group chairman Kieth King of Gilat Wavestream, for the hard work and careful thought they have put into developing the process, the important milestone they’ve reached and the continuing effort to evolve processes that advance market confidence and meet market needs.

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Is AI Another Bridge Between Space and Terrestrial Networks?

2/25/2025

NVIDIA released its third annual State of AI in Telecommunications Report, reporting that 97% of respondents are “assessing or adopting AI with the goals of enhancing customer experiences and employee productivity, improving network operations, reducing costs, and opening new business opportunities.” Half of respondents said that they have already implemented their first generative AI use case.

There’s no reference for the satellite portion of the telecom industry, but even if implementation in our corner of the market lags, many see the potential benefits and many satellite, mobile and terrestrial network operators are exploring options for managing network operations. Unfortunately, the state of our legacy hardware ground systems may slow us down even more. It is simply much harder to implement robust and dynamic optimization and automation for an analog system. There are limits to what you can do when it comes to collecting and fusing data for the AI algorithms to use.

In contrast, virtualizing ground infrastructure with a digital IF architecture at or close to the antenna provides easy access to any data required to enable optimization or automation. Data from every stage of routing and processing is accessible making it far easier to collect, train and deploy AI and ML models.

For example, suppose an operator wanted to optimize network performance and minimize teleport power requirements by automatically adjusting network configuration and amplifier gains based on historical and actual traffic patterns. That requires data from multiple diverse systems that are today managed in different, stovepiped ways. With virtualized and orchestrated signal routing and processing, however, network and teleport infrastructure run in the same compute environment, enabling the AI to access the full range of applicable information. What’s more, it enables incorporation of longer-term trending data that can’t be accessed via hardware today.

According to NVIDIA, integrating AI Into network operations is gaining traction at communications service providers. “Investing in AI solutions for network infrastructure has become a growing priority within the telecom industry. Network planning and operations, including integrating AI into the radio access network, was cited by 37%

of respondents as an investment priority, while another 33% said they’re investing in AI for field operations optimization.”

AI is one more growing surface for satcom integration with terrestrial infrastructure. Combine it with global initiatives uniting the two worlds behind 5G NTN and 6G, and the opportunity for satellite to grow market share looks even brighter. In fact, the NVIDIA report specifically cites using AI to monetize 5G and research and development of 6G networks as key investment areas for telecom companies. But it will require our respective systems to work together better than they do today.

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When in Doubt, Get Horizontal

1/29/2025

No, it’s not nap time. Anything but.

Facing the massive disruptions Starlink and the other mega-constellations are driving in the space industry, many are focusing on the impact vertical integration has as a driver of at least part of Starlink’s success.

With one or two exceptions, companies in our industry have historically specialized in sectors: satellite manufacturers, launch, operators and ground systems. The ecosystem starts there with sectors supporting each other. Vertical integration is when a company takes on developing solutions in or across more than one sector, perhaps even all of the supply chain. Doing so brings certain scale advantages, especially as the number of satellites in a constellation increases.

Starlink has changed our world. The company is playing a different game from traditional satellite operators, building a worldwide communications infrastructure in space that targets scale and delivery costs competitive with fiber. Traditional satellite operators have never designed systems for this type of scale or at the price points that this level of scale enables.

If that’s so, how to compete? No single simple solution, of course, but a key piece of the puzzle will be to counter going vertical by going horizontal. That means, at least in part, open standards, especially 3GPP and DIFI. And it’s for a reason often overlooked in such discussions: standards widen the available solution pool for integration, applications and partners. Their downstream effect is to spur innovation, speed to market and flexible solutions. Think IBM PC vs. Apple in the 80’s. Apple maintained control, but PCs had tens of thousands of times the available software.

Vertical integration allows a company to milk cost out of the manufacturing process, which contributes to lower prices, but like anything else there are trade-offs. At a recent APSCC conference covered by Constellations content partner Space Intel Report, Intelsat’s Asia-Pacific director, Robert Suber, commented that 3GPP’s integration of satellite capacity for 5G and beyond will be a problem for vertically integrated operators.

“The vertically integrated players are going to be on the outside,” Suber said. “If 5G will be a form of standardization for GEO operators, we will be horizontally integrating with those businesses. Proprietary technology will keep us in cottage-industry mode. We need to come together to be part of a greater ecosystem.”

The road ahead for the traditional satellite industry is not an easy one. It is being disrupted by scale in several dimensions, potentially at levels we have not dealt with in the past. The responses lie in finding ways to either achieve similar scale or to plug into scale through better integration with global network players.

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