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A panel at the Defense Communications Forum put timelines on drone detection, waveform debates, and the limits of sensing from space
At the Defense Communications Forum, a panel moderated by the GSMA’s James Joiner dissected where integrated sensing and communications (ISAC) actually stands for the defense sector — what’s deployable now, what’s coming with 5G Advanced, and what’s still several 6G releases away. The discussion brought together Chris Christou, SVP of NextG and AI-RAN at Booz Allen Hamilton; Alain Mourad, Chair of the ISAC industry specification group at ETSI; and Dr. Anton Monk, SVP of strategy at Cohere. The framing throughout was pragmatic. Commercial mobile operators treat defense as another enterprise vertical, weighing the cost of ISAC support against the revenue opportunity — and they’re not keen to give up network capacity to do it.
Primary defense use cases
Drone detection is the clear front-runner. “I think the first use case that we’re seeing a lot of potential customers interested in is, of course, drone detection. That’s at the top of mind of so many organizations, not only defense, but even more broader than that, whether it be aviation industry or even out to some of the commercial industries as well,” Christou said. Beyond counter-UAS, defense buyers are asking about base and force protection, and missile defense scenarios where the same sensing primitives apply.
There’s meaningful overlap with enterprise use cases too — smart warehousing, anomaly detection, and search and rescue all pull on similar capabilities. Mourad pointed out that the use cases being defined inside 3GPP and ETSI aren’t sector-specific by design, but the linkage isn’t subtle. UAV detection and tracking became the focal point of 3GPP’s 5G Advanced ISAC work, and as he put it, “it doesn’t take much imagination, actually, to link them to defense use cases.”
Development timelines and standardization
ISAC isn’t entirely a future-tense conversation though. Pre-standard offerings built on existing 5G frameworks are already in market — Orange Business’s drone-detection solution got name-checked more than once. ETSI’s ISAC group, which Mourad chairs, sits deliberately upstream of 3GPP and is acting as a catalyst for solutions that don’t wait for 6G to ship.
3GPP, meanwhile, is targeting ISAC baselines as part of 5G Advanced, with most of the heavy lifting pushed into 6G. Mourad’s timeline estimate was blunt: the full set of use cases now on the table — 32 in 5G Advanced, 18 from ETSI, 21 in early 6G work at 3GPP — will take multiple releases to enable. “It’s at least a five to 10 years ahead kind of timeline before we can say that we enabled the most, or all of the use cases that we have today,” he said.
Monk framed the rollout as inherently phased, with networks initially looking for anomalies using existing reference signals and then dialing up resources — more PRBs, more power, more spatial capacity — once something interesting shows up. The harder question, he argued, isn’t whether 5G as-is can do sensing. It’s how open the standards process is to genuinely new capabilities.
The waveform debate and performance parameters
3GPP is moving fast to lock OFDM in as the ISAC baseline, and Monk doesn’t think that’s good enough for the use cases that matter most. “when it comes to real radar, nobody’s using OFDM. You know, there’s no defense community that is using OFDM. They’re using chirps or something else.” Defense radar has avoided OFDM for reasons — high-speed and long-distance tracking performance among them — and Cohere is advocating for its OTFS waveform, which carries information in the radar domain, as a way to hit national-security-grade performance without burning commercial bandwidth.
Monk’s concern is that “good enough” carries real consequences here. Detecting a fall in someone’s home is a binary problem where adequate performance is fine. Detecting a small, high-Doppler drone three to five kilometers from a base station is not. “The risk of just accepting good enough is that there are real national security concerns present, and we should be doing everything we can for these types of critical use cases to bring performance.”
Mourad floated a middle path. OTFS has characteristics genuinely well-suited to radar, but a modified OFDM — perhaps with chirps layered on when sensing is triggered — might land in a sweet spot. Sensing won’t run 24/7 across the full bandwidth, the argument goes, so a lighter-weight, opportunistic mode could cover the use cases at a fraction of the cost. He also noted that RF sensing won’t be working alone. Radar, lidar, and cameras will all be in the mix, which changes the calculation for how much performance you really need to extract from the cellular waveform.
The constraint everyone agreed on was coexistence. Whatever waveform you pick, it has to sit alongside existing 5G traffic without eating into commercial revenue. Monk pointed out that OTFS can be overlaid below the noise floor or scheduled alongside other packets in the mMRS framework, and that for monostatic or single-vendor bistatic deployments, infrastructure vendors have a lot of latitude to innovate without needing a standardized air interface at all. Christou’s take from the defense buyer side was more wait-and-see — there’s plenty of pre-standard work happening, including approaches that tap the O-RAN open fronthaul interface for IQ samples, and the waveform question will resolve itself as the standards mature.
Non-terrestrial networks capability
NTN is where the panel’s enthusiasm collided most visibly with technical reality. The geographic coverage argument is compelling — defense customers want sensing over vast areas that terrestrial networks will never reach. But, direct RF sensing from space is hard. Path loss is brutal, and the power required to bounce useful radar returns off a target is a serious constraint.
Monk was candid about the gap between interest and evidence. “I don’t think anybody has — well, nobody that I know — has real answers around sensing from space.” Golden Dome and similar initiatives have pushed the topic up the agenda, but the academic and industrial body of work is still thin compared to the terrestrial side.
What’s more realistic in the near term is using NTN as a supporting layer. Mourad described scenarios where satellite-derived data is combined with terrestrial sensing, or where satellite positioning underpins ISAC use cases without the satellite itself doing the RF sensing. Bistatic and multi-static configurations — satellite transmits, terrestrial nodes receive — could also relax the link budget problem considerably. Christou raised a related angle — using ISAC to make NTN networks more context-aware, improving the performance of the network itself rather than purely sensing external targets.
Operational risks and security mitigation
Combining a comms system and a radar system also means combining their attack surfaces. Jamming, spoofing, and the rest of the electronic warfare toolkit all apply, and Monk’s view was that targeting is essentially guaranteed. “We’ve already seen day one targeting of networks, so we should just assume that’s going to happen.”
That makes single points of failure a non-starter. The answer the panel converged on was distributed sensing — heterogeneous networks with orchestration across satellite, terrestrial, and tactical edge nodes, lightweight gNodeBs deployed forward, and UEs (custom or otherwise) acting as distributed sensors. The technical catch is coherent synchronization across all of it. Distributed MIMO is starting to tackle pieces of this, but coherent distributed synchronization at the scale ISAC implies is a much harder problem, and it’s one that several academic groups and the national spectrum consortium’s ISAC working group are actively working on.
Christou pointed to AI and machine learning as a necessary layer in the mitigation stack — anti-jam, anti-spoof, anomaly detection — and noted that the industry hasn’t really started combining the mitigations for comms and radar threats into a unified approach yet. That work is still ahead.
The overall takeaway from the panel was measured. ISAC’s relevance to defense is clear, and early capabilities are already in market. Readiness is the harder question — the waveform debate isn’t settled, NTN sensing is more aspiration than capability, and the resilience architecture needed to survive contested environments is still being figured out. Five to 10 years is the working assumption for when this all really lands.
