TTP plc, the Cambridge-based technology and product development company, announced on June 15, 2026 that it is building a software-defined 5G Non-Terrestrial Networks (NTN) modem module designed specifically for next-generation Ku- and Ka-band satellite terminals. The modem, still in development, promises an open architecture that allows satellite operators and terminal manufacturers to update waveforms, protocols, and features entirely via software — a sharp break from the fixed-function hardware that dominates today’s satcom links.
TTP’s move targets the growing push to converge terrestrial 5G and satellite communication under the 3GPP’s Release 17 and 18 NTN specifications. By moving the entire physical-layer processing into a reprogrammable digital fabric, the company aims to slash the cost and complexity of user terminals while making them future-proof against evolving standards and orbital configurations.
A Modem Built for the 5G Space Age
Traditional satellite modems rely heavily on application-specific integrated circuits (ASICs) or fixed-function field-programmable gate arrays (FPGAs) that lock in a particular waveform and channel bandwidth. When a new modulation scheme or beam-hopping pattern emerges, operators must frequently swap out hardware. The TTP modem, by contrast, uses a software-defined radio (SDR) approach that runs the entire NTN protocol stack — from the physical layer through the medium access control (MAC) — on a general-purpose processing platform coupled with wideband RF front-ends.
“We’re delivering a completely open, software-updatable baseband that can handle the extreme Doppler shifts, long delays, and high path losses of Ku- and Ka-band links without sacrificing spectral efficiency,” said Dr. Matt Collins, head of the NTN programme at TTP, during a briefing at the company’s headquarters. The modem is being designed to support both transparent and regenerative payload architectures, giving terminal builders the flexibility to target geostationary (GEO), medium-earth orbit (MEO), and low-earth orbit (LEO) constellations with a single hardware platform.
The initial prototypes operate across 10.7–12.75 GHz (Ku-band downlink), 14.0–14.5 GHz (Ku-band uplink), 17.7–20.2 GHz (Ka-band downlink), and 27.5–30.0 GHz (Ka-band uplink), covering the most widely used commercial satcom frequencies. TTP engineers have implemented adaptive coding and modulation (ACM) up to 64APSK, support for carrier bandwidths from 1.4 MHz to 100 MHz, and dual-polarisation MIMO to double throughput per terminal.
Why Software-Defined Matters Now
The satcom industry is in the middle of a radical transformation. Non-geostationary constellations — from SpaceX’s Starlink to Amazon’s Project Kuiper to OneWeb — are pouring thousands of broadband satellites into LEO, while 3GPP’s NTN work item bakes satellite access directly into the 5G standard. What’s missing, according to TTP, is a terminal modem that can keep pace with the rapid innovation cycle.
“Every new generation of satellite modem forces operators to make a painful decision: wait for the next ASIC tape-out — which can take 18 months and cost tens of millions — or deploy a sub-optimal FPGA-based interim solution,” Collins explained. “Our software-defined approach allows a firmware update to add 5G NR over NTN, switch between DVB-S2X and 5G waveforms, or enable new interference-mitigation algorithms in the field. That’s a game-changer for terminal total cost of ownership.”
The timing is critical. The European Space Agency and multiple national regulators are funding trials of direct-to-handset and fixed-wireless satellite services. TTP’s modem is designed to serve both enterprise VSAT markets and the emerging consumer broadband segment, where updatability is essential. An over-the-air update can fix a protocol bug or improve beam tracking without a truck roll — a capability that terrestrial cellular operators have exploited for years but that remains rare in satcom.
Open Architecture: Inside the Black Box
TTP is not merely building a product; it is advocating for an open ecosystem. The modem’s reference design will ship with an open application programming interface (API) that lets terminal developers tune every layer of the protocol stack. A published software development kit (SDK) will allow third parties to create custom waveforms, integrate proprietary mesh-networking algorithms, or optimise the L1 scheduler for a specific constellation’s beam layout.
This openness extends to hardware. TTP is partnering with several RF chipset vendors to ensure the digital baseband can pair with a variety of off-the-shelf Ku/Ka-band front-ends, avoiding vendor lock-in. Early samples use a combination of Xilinx Zynq UltraScale+ MPSoCs and Lime Microsystems’ LMS8001 wideband transceivers, but the modular architecture is designed to be chipset-agnostic. Terminal manufacturers can swap RF components as supply chains or performance requirements change, without redesigning the entire modem.
“We’re open-sourcing the modem’s hardware abstraction layer and contributing reference implementations of the 5G NTN physical layer to the O-RAN Alliance’s open-source community,” said Dr. Sarah Bennett, TTP’s principal engineer on the project. “Our goal is to turn satellite terminals into software platforms, much like smartphones evolved from fixed-function phones.”
The modem’s software stack builds on OpenAirInterface, an open-source 5G codebase widely used in research and small-cell deployments. TTP has added custom extensions for NTN-specific challenges: Doppler pre-compensation (up to ±750 kHz), timing advance loops for variable propagation delays, and HARQ (hybrid automatic repeat request) procedures adapted for the 500+ millisecond round-trip times of GEO links.
Performance Targets and Early Benchmarks
In anechoic chamber tests completed in May 2026, the pre-production modem achieved an error-vector magnitude (EVM) of 2.1% for a 64APSK signal at 100 MHz bandwidth — well within the 3GPP’s specified limits for 5G NTN waveforms. Doppler tracking algorithms maintained lock during simulated LEO passes with a rate-of-change of 15 kHz/s, and the soft modem successfully switched between DVB-S2X and 5G NR modes in under 50 milliseconds without dropping the link.
Throughput measurements on a 100 MHz Ka-band link showed 930 Mbps downlink and 230 Mbps uplink when configured with 8×8 MIMO and 256QAM in the downlink, though such high-order modulation is practical only in high-gain, rain-fade-compensated terminals. The team expects field trials with a commercial Ku-band antenna to begin in Q4 2026, with production-ready modules sampling to terminal vendors by mid-2027.
Power consumption, often the Achilles’ heel of software-defined radios, is a priority. The current prototype draws approximately 25 W for a fully loaded 100 MHz channel, including the RF front-end. TTP aims to reduce this to under 15 W through migration to 7 nm process ASICs for the digital portion while preserving software update capability via a hardened RISC-V core array. “We’re not naively trying to beat an ASIC on power — we’re targeting power parity with today’s best fixed-function modems while adding full programmability,” Collins noted.
Industry Reactions and Competitive Landscape
The announcement has drawn keen interest from satellite operators and terminal OEMs. Several major players, including Inmarsat and Hughes Network Systems, have been investing in software-defined platforms, but TTP’s open-access philosophy sets it apart. “What TTP is doing moves the industry toward a model where the modem is a commodity with a rich app ecosystem,” said Dr. Rajeev Gopal, a satellite communications consultant and former Hughes executive. “The real locking factor will be who controls the waveform and scheduling software, and TTP seems willing to hand those keys to the operator.”
Other competitors are pursuing similar paths. ST Engineering iDirect launched its “OpenAM” platform in 2025, aiming to decouple software from hardware in hub-side infrastructure, while SpaceX’s Starlink terminals already use a software-defined baseband, albeit one closely guarded. TTP’s edge may lie in its independence: as a technology development house without a competing terminal product, it can collaborate with any manufacturer.
Skeptics, however, question whether an open SDR modem can match the ruggedness and power efficiency required for consumer outdoor terminals, especially in the expansive Ku/Ka-band market where antenna pointing and signal-to-noise margins are already challenging. TTP counters that its reference design includes an outdoor-rated enclosure and integrated control loops that work with any phased-array or parabolic antenna, simplifying the terminal integrator’s job.
Standards Alignment and 3GPP Timeline
The modem targets compliance with 3GPP Release 18, which enhanced NTN support with features such as store-and-forward operation, improved mobility, and S-band spectrum compatibility for IoT. Critically, Release 18 introduced the NR-NTN air interface for satellite direct-to-device (D2D) services, and TTP’s modem is designed to handle both the IoT-NTN (narrowband) and NR-NTN (broadband) profiles. The software-defined nature means future upgrades to Release 19 and beyond — including support for regenerative payloads and inter-satellite links — can be rolled out without hardware changes.
“We are actively participating in 3GPP RAN working groups and contributing to the specification of NTN test cases,” Bennett stated. “Our platform will be available for operator labs and standards bodies to accelerate interoperability testing.” This alignment positions TTP as a key enabler for the scheduled commercial launch of 5G NTN services by several operators in 2027–2028.
The Road Ahead
TTP plans to demonstrate the modem at the World Satellite Business Week in Paris this September, showing a multi-mode terminal that seamlessly switches between a geostationary Ku-band link and a simulated LEO Ka-band link — all driven by the same hardware. The company is also in discussions with multiple satellite operators to conduct on-orbit trials using existing GEO capacity.
The broader significance of TTP’s announcement may be in signaling a maturation of the software-defined satcom market. As terrestrial 5G networks increasingly incorporate non-terrestrial components, the ability to update terminals remotely will become a baseline requirement. The days of shipping a dish that becomes obsolete with the next standard revision are numbered.
For Windows and PC enthusiasts watching the satcom space, this development is particularly relevant. Microsoft’s Azure Orbital and emerging Windows integration for satellite-backed internet connectivity — as demonstrated in recent Windows Insider builds — rely on agile, software-updatable ground terminals. TTP’s open modem could become the unseen engine inside the next generation of always-connected Windows devices, from rural broadband terminals to mobile command centers.
In Cambridge, TTP’s team is already looking beyond the initial release. Work is underway on a smaller variant for direct-to-handset applications, and a collaboration with an unnamed automotive supplier aims to embed the modem in connected-vehicle roof modules for truly global coverage. If the field trials succeed, the 5G NTN modem might soon be as ubiquitous as the Wi-Fi chipset — invisible, essential, and forever updatable.