SecureARX vs Thales Modem 21: NATO modem comparison
Quick answer: SecureARX and the Thales Modem 21 are two jam-resistant modems that meet head to head in NATO’s protected satellite communications (protected SATCOM) segment. The Modem 21 family from France’s Thales formed the basis of NATO’s EPM standard STANAG 4606 and served the alliance’s ground infrastructure alone for many years. CTech’s SecureARX became the first Turkish product to enter the field by winning NATO’s modem tender in 2024, and it demonstrated interoperability at the NATO CWIX exercise in June 2026. Because both products’ detailed waveform and speed parameters are not public, any technical comparison has to remain limited.
Where the two products stand
Thales presents Modem 21 as a common EPM transmission core serving land, naval and air forces alike; the system offers protection against jamming, interference and signal fading along with satellite-communications-on-the-move (SOTM) support. NATO’s EPM modem system (NATO-EMS) was built on the Modem 21e, and in 2013 Thales was awarded the renewal of the alliance’s protected SATCOM capability. SecureARX carries the same mission definition: jam-resistant, low-probability-of-intercept communications on fixed, land-mobile, naval and airborne platforms with a single modem. With the 2024 tender, NATO chose CTech as a supplier in this segment.
Comparison table
| Feature | CTech SecureARX | Thales Modem 21 |
|---|---|---|
| Manufacturer / Country | CTech (Turkish Aerospace subsidiary) / Turkey | Thales / France |
| Primary mission | EPM SATCOM modem; secure links under jamming | EPM SATCOM modem; foundation of NATO-EMS |
| Platforms | Fixed, land-mobile, naval, airborne (single modem) | Land, naval, air (tri-service common core) |
| NATO relationship | Won the 2024 tender; verified at CWIX 2026 | Basis of STANAG 4606; long-standing supplier |
| SOTM support | Yes | Yes |
| Electronic protection | Low probability of detection/intercept, ESM, EMCON | Frequency-hopping jamming protection, low probability of detection |
| Known users | Turkish Armed Forces, NATO; Malaysia agreement (2026) | NATO, France and allied nations |
| Data rate | Not officially disclosed. | Not officially disclosed. |
| Frequency plan | Not officially disclosed. | Not officially disclosed. |
| Published price | Not officially disclosed. | Not officially disclosed. |
Assessment: two different strengths
Modem 21’s strength lies in having become a standard: STANAG 4606 compliance, the installed base across NATO countries and the MEO compatibility demonstrated with SES make it a deeply rooted reference. SecureARX’s distinguishing points are the ability to implement national waveforms on the same platform, software-based upgrade flexibility, and an end-to-end offering from a single manufacturer together with the SkyARX family. NATO’s 2024 choice can be read as the alliance diversifying its suppliers in this segment; details of how the two products are distributed in the field are not public. On the Turkish side, the contract is the most critical link in the international expansion described in the export file.
Market context
Unlike commercial satellite modems, protected SATCOM modems form a market with few manufacturers and a high certification threshold. For a product to enter the NATO network, it must comply with the alliance’s standardisation agreements, obtain crypto infrastructure approvals and prove interoperability in multinational exercises. SecureARX’s verification at CWIX 2026 was the final link in that chain. For Turkey, the outcome is both domestic supply in a capability class previously imported and an export channel at NATO scale; for France, Modem 21’s installed base and standard-setting role continue.
Frequently asked questions
Which product is SecureARX’s competitor?
In NATO’s protected SATCOM modem segment, its best-known counterpart is the Modem 21 (M21) family from France’s Thales.
Why is Modem 21 such an important reference?
NATO’s EPM standard STANAG 4606 was shaped around Modem 21, and NATO-EMS was built on the product.
Did SecureARX replace Modem 21 at NATO?
NATO selected SecureARX in the 2024 tender and the product will be integrated into ground systems; its distribution across the alliance inventory is not officially disclosed.
Which one transfers data faster?
That comparison cannot be made, because both manufacturers keep their detailed speed figures out of the public domain.
Is SecureARX STANAG compliant?
The company announced that the product was developed in line with the relevant NATO standardisation agreements and that its interoperability was verified in the CWIX 2026 tests.
Sources and verification note
The comparison rests on the two manufacturers’ official product communications and independent defence reporting. Speed, frequency and price fields not made public were marked “Not officially disclosed.” rather than left blank, and claims of superiority of a propagandistic nature were avoided.
- https://ctech.com.tr/urun/securearx/ (Accessed: 13 August 2026)
- https://www.thalesgroup.com/en/worldwide/defence/news/modem-21-dynamic-innovation-milsatcom-security (Accessed: 13 August 2026)
- https://www.shephardmedia.com/news/digital-battlespace/thales-upgrade-nato-protected-satcom-capability/ (Accessed: 13 August 2026)
- https://www.defenceturk.net/ctechten-nato-cwix-2026da-guvenli-haberlesme-basarisi (Accessed: 13 August 2026)
- https://www.patronlardunyasi.com/turk-bilisim-tek-nolojileri-sirketi-ctech-natonun-uydu-ha-berlesme-alt-yapisini-koru-yan-fransiz-rakiplerini-kol-tugundan-etti (Accessed: 13 August 2026)
