Choosing radios for defence deployments: A guide to defence RF communication systems

The importance of secure RF communication for military-grade deployments

This post is our sixth in a series within a growing body of work we have produced for the UK defence sector, covering the electronics and firmware challenges specific to military-grade hardware. This particular guide focuses on radio frequency (RF) communication technology: the wireless links that connect sensors, drones, command nodes, and personnel in the field. Defence RF communication systems form the backbone of modern military operations as they provide secure, real-time command, control, and coordination across ground, air, and naval units. Without them, tactical awareness, drone operations, and rapid response capabilities would be severely compromised and increase the risk of espionage, interception, and data breaches. 

This is a topic that bridges electrical engineering, systems integration, and procurement, and is pertinent regardless of whether you are specifying a new device or reviewing a supplier.

Why is radio selection a systems-level decision in defence?

In commercial product development, radio selection is often straightforward: choose a module certified for the target market, confirm it meets the data rate requirement, and move on. Defence deployments do not work that way. The choice of RF technology reaches into antenna design, power budgets, spectrum management, cybersecurity policy, interoperability requirements, and ultimately into operational doctrine.

A sensor node that works well at 868 MHz in a logistics warehouse may be entirely unsuitable for a forward operating base where the same frequency band carries hostile jamming, co-channel interference from allied equipment, or regulatory restrictions tied to specific operating theatres. The radio is not a commodity component in these contexts; it is a critical system element.

This post builds on earlier entries in this series, particularly our work on LoRa for defence sensor networks, tactical sensor power design, and EMI and EMC in defence electronics. If you have not read those posts, the links are worth following before diving into radio selection, as the constraints they describe directly affect which RF technologies are viable for a given deployment.

The UK defence landscape for radio equipment use

The UK defence radio landscape is undergoing an extensive modernisation phase under the Tactical Communications and Information Systems (TacCIS) portfolio. The imperative is to move away from legacy systems and focus on achieving secure, resilient, AI-enabled, and multi-domain connectivity in contested electronic warfare (EW) and conflict environments. One example cited in a MOD press release refers to British soldiers getting new AI-capable radios, headsets, and tablets with futuristic sensor data to help them make faster and better decisions in high-pressure situations. 

Understanding who governs military radio use in the UK is a prerequisite for anyone designing or procuring spectrum-dependent hardware for the UK Ministry of Defence (UK MoD). Civilian radio use falls under Ofcom (Office of Communications), which operates under the Communications Act 2003 and the Wireless Telegraphy Act 2006 and is responsible for licensing and spectrum management for commercial and public users. 

However, military use is different: the Wireless Telegraphy Act does not bind the Crown, which means Crown Bodies (i.e., UK government departments and agencies), including the MoD, do not require Ofcom authorisation to install or use radio equipment. Instead, military spectrum is administered under Crown Use by the MoD’s Defence Spectrum Management (DSM) team.

DSM is responsible for MoD spectrum policy, day-to-day management of military frequency allocations, and coordination with Ofcom where military and civilian spectrum interests overlap. A practical example of this coordination is the 2.32 to 2.34 GHz band: following years of discussion, the MoD agreed to share access with civil users for low-power private mobile networks in 2024, while retaining use of the lower portion of the band for defence purposes. 

In early 2025, the MoD similarly worked with Ofcom to release the 26.5 to 27.5 GHz band for commercial wireless services, including 5G. These releases illustrate the ongoing negotiation between military spectrum requirements and commercial demand, managed through the UK Spectrum Board and DSIT as the lead government department for spectrum policy.

For hardware developers, the practical implication is clear: defence spectrum authorisation goes through the MoD’s Defence Electromagnetic Authority (DEMA), not Ofcom. New spectrum-dependent equipment must be registered with DEMA’s Electromagnetic Management (EMM) function early in the programme, with final approval required before operational deployment. This is a separate and additional process to the DEF STAN compliance and type approval pathway.

A transitioning regulatory landscape: MANET, AI-enabled comms, and RF weapons

Beyond the regulatory framework, the UK defence RF landscape is undergoing a significant operational shift. Traditional centralised, single-band radio architectures are giving way to resilient Mobile Ad Hoc Network (MANET) radios that can self-heal around node loss or jamming, AI-enabled tactical packages that adapt waveform and frequency selection in real time, and an entirely new category of RF capability: directed energy weapons.

On the MANET front, the UK Royal Marines fielded more than 2,000 MPU5 MANET radios from Persistent Systems in 2024 as part of their transformation into a technology-enabled Commando Force. In March 2026, the MoD selected the same Wave Relay platform for the British Army’s Project CAIN programme, with hardware going to the 16 Air Assault Brigade Combat Team. These deployments reflect a broader shift in UK tactical communications away from proprietary, vendor-locked radio architectures toward open, software-updatable systems capable of operating in mesh configurations.

The flagship replacement for the legacy Bowman tactical communications system was initially intended to be the Morpheus Programme: a £3.2 billion effort to deliver next-generation tactical communications and information systems to land forces. The programme’s overhaul efforts faced significant setbacks, leading to the termination of the contract with General Dynamics UK for the core Evolve to Open (EvO) after the supplier failed to meet contractual milestones. Initial operational capability, originally planned for 2025, is now not expected until the 2030s. The Multi-Mode Radio (MMR) project, a related element of the Land Environment Tactical Communications and Information Systems (LETacCIS) programme, has progressed more successfully, with delivery into service tracking ahead of schedule.

The Morpheus situation is a relevant case study in the risks of large-scale bespoke defence communications programmes, and it underscores why procurement teams are increasingly looking at commercially proven MANET platforms as interim or complementary solutions.

RF directed energy weapons: A new operational dimension for RF engineers

The most consequential recent development in UK defence RF is the emergence of operational Radio Frequency Directed Energy Weapons (RFDEWs). These are not communication systems, as their function is to emit concentrated beams of electromagnetic energy to disrupt or destroy electronic components of targets like drones or smart weapons. These devices are built on RF engineering principles and are reshaping the threat and capability landscape that communication system designers must account for.

The UK’s RFDEW programme, known as Project Ealing and delivered by Team Hersa (a collaboration between Defence Equipment and Support and Dstl), has produced the RapidDestroyer demonstrator, developed by an industry consortium led by Thales UK and including QinetiQ, Teledyne e2v, and Horiba Mira. Rather than jamming drone control signals, RapidDestroyer uses high-power microwave emissions to physically destroy the electronic components inside target drones, causing them to crash or malfunction regardless of the control link used. This distinction matters: a conventional jammer is ineffective against drones controlled by fibre optic tether or pre-programmed autonomous flight, whereas an RFDEW is not.

Field trials conducted by the British Army’s 7th Air Defence Group in December 2024 and at Air Defence Range Manorbier in April 2025 successfully tracked, targeted, and destroyed more than 100 drones across multiple engagements, including the simultaneous defeat of two swarms in a single engagement. The system engages targets up to one kilometre away and carries an estimated cost per shot of approximately 10 pence, compared with tens of thousands of pounds for a conventional missile. The UK government has invested more than £40 million in RFDEW research and development to date. As of mid-2025, the MoD had not yet approved transition to operational service, but further capability development is ongoing.

Key RF technologies for defence deployments: A comparative overview

HF (3 to 30 MHz): Long-Range, Low-Bandwidth Ground-Wave and NVIS

HF radio remains operationally relevant for long-range communications where satellite links are unavailable or have been denied. Near-Vertical Incidence Skywave (NVIS) propagation allows HF links to cover regional distances, typically 50 to 500 km, without line-of-sight requirements. Data rates are low, typically 75 bps to 9600 bps on modern HF modems, which limits HF to voice, low-bandwidth telemetry, and messaging.

For sensor and IoT applications, HF is rarely the primary link, but it has a role as a resilient fallback in contested environments where other frequencies have been jammed or blocked. Integration with legacy MoD HF infrastructure, including HARRIS and Barrett equipment, remains a real design constraint for new hardware.

VHF/UHF (30 MHz to 3 GHz): The Tactical Backbone

VHF and UHF bands carry the bulk of UK tactical communications, including encrypted voice and data under the Bowman system. As noted above, Bowman is being extended while Morpheus is delayed, and MANET platforms operating in the UHF range are filling capability gaps in the interim. Most soldier-worn radios, vehicle-mounted systems, and fixed ground stations operate in this range.

For hardware developers integrating into the UK tactical network, UHF and VHF interoperability remains essential. Software-Defined Radio (SDR) platforms have become increasingly common in this space, as they allow waveform updates without hardware replacement. Our post on secure OTA updates for defence IoT is directly relevant here: the ability to push certified waveform updates to fielded SDR units is a genuine operational capability, and one that requires careful design of the update pipeline.

Software-Defined Radio (SDR): Flexibility at a Cost

SDR platforms replace fixed-function radio hardware with reprogrammable digital signal processing. A single SDR unit can, in principle, implement multiple waveforms across a range of frequency bands by loading different software. This makes SDR attractive for defence procurement, where requirements evolve faster than hardware development cycles and where interoperability with multiple allied force structures is a standing requirement.

The trade-off is complexity. SDR platforms require rigorous software assurance, and the waveform software itself must be certified before operational deployment. NCSC cryptographic requirements apply to waveforms carrying classified traffic, and the waveform software stack should be treated as a high-criticality embedded software project, subject to similar rigour as the firmware standards discussed in our post on secure OTA for defence IoT.

LoRa and LPWAN: Sensor Networks at Long Range

As covered in depth in our dedicated post on LoRa for defence sensor networks, LoRa offers a useful combination of range, low power consumption, and small payload sizes for distributed sensor applications. Ranges of 5 to 15 km are achievable in open terrain, with data rates typically between 0.25 and 11 kbps depending on spreading factor and environmental conditions.

LoRa is not suitable for voice, video, or high-throughput telemetry, but for periodic sensor reporting, asset tracking, and environmental monitoring in forward-deployed networks, it provides a credible capability. The key defence-specific constraints remain frequency authorisation through DEMA (not ISM band assumptions), anti-jam margins, and the absence of native encryption in LoRa PHY, which requires application-layer security to be built explicitly into the system design.

MANET and Mesh Networking: Resilience for Contested Environments

As recent UK procurement decisions confirm, Mobile Ad Hoc Network (MANET) architectures have moved from specialist capability to mainstream procurement choice for dismounted and vehicle-mounted tactical communications. MANET platforms such as Persistent Systems’ MPU5, now fielded by both the Royal Marines and the 16 Air Assault Brigade, provide self-healing mesh topologies where nodes can reroute traffic around damaged or jammed links, and support high-throughput data sharing across a distributed network without reliance on fixed infrastructure.

These platforms increasingly incorporate AI-assisted frequency and waveform management, allowing the network to adapt dynamically to the electromagnetic environment rather than relying on pre-planned frequency assignments. For hardware developers integrating sensors or payloads into MANET-enabled platforms, understanding the data interface requirements, latency characteristics, and network prioritisation policies of the chosen MANET platform is essential for early design work.

Satellite Links: SATCOM for Extended Range and Denied Environments

Where terrestrial RF links are unavailable or have been denied, satellite communications (SATCOM) provide a resilient alternative. UK defence SATCOM capabilities are anchored by the Skynet 5 and Skynet 6 programmes, with additional reliance on NATO satellite systems and commercial SATCOM providers for surge capacity. Low Earth Orbit (LEO) constellations have been used operationally in recent conflicts, though their formal integration into UK MoD architecture is still evolving.

For hardware developers, integrating SATCOM capability requires awareness of terminal size and power constraints, latency (which affects protocol design significantly), and COMSEC requirements for link encryption. High-latency links introduce protocol design challenges that are worth addressing at the system architecture stage, not during integration testing.

Critical design parameters for defence RF communication systems

Frequency Agility and Anti-Jam Capability

Fixed-frequency radios are inherently vulnerable to spot jamming. Defence-grade RF systems use frequency agility techniques, including Frequency-Hopping Spread Spectrum (FHSS) and Direct Sequence Spread Spectrum (DSSS), to reduce jamming susceptibility. FHSS systems hop across a defined frequency set at rates of up to several hundred hops per second, making it difficult for a jammer to track the signal.

When designing or selecting radios for deployments where electronic warfare (EW) is a credible threat, anti-jam margin should be specified as a performance requirement and carried through into link budget analysis. The anti-jam margin is typically expressed in dB and represents the additional jammer power required to degrade the link beyond a defined threshold.

Low Probability of Intercept and Low Probability of Detection

LPI (Low Probability of Intercept) and LPD (Low Probability of Detection) are design characteristics that reduce the risk of an adversary detecting or intercepting a radio transmission. Techniques include burst transmission, low power operation, spread spectrum, and directional antennas. LPI/LPD design involves trade-offs: burst transmission reduces dwell time but increases latency, and directional antennas improve LPI but constrain mobility.

For sensor networks and UAV data links, covered in our post on MAVLink integration in defence UAVs, LPI/LPD requirements should be specified at the system level and carried through into radio selection, antenna design, and protocol design. The growing use of RFDEW systems, which can engage targets regardless of the control link, adds a new dimension to the threat model that LPI/LPD design alone cannot address.

Latency and Data Throughput

Different mission types impose different latency and throughput requirements. Command and control typically tolerates higher latency than real-time video downlink. Autonomous system control loops may require sub-100 ms round-trip times. Remote weapon stations and targeting systems may have even tighter requirements that rule out high-latency links such as SATCOM without dedicated acceleration.

Protocol design choices interact directly with latency. The MAVLink protocol discussed in our UAV post is optimised for low-overhead telemetry at moderate latencies. Applications requiring reliable delivery over lossy links should evaluate whether a forward error correction (FEC) layer is appropriate, and what the latency penalty of retransmission or FEC decoding would be in practice.

Power Consumption and Battery Life

Power constraints are a dominant factor in deployed sensor and wearable radio design, covered in depth in our post on tactical sensor power design. The key principle is that radio transmit power consumes disproportionately more energy than receive or processing states, so duty cycle management and transmit power minimisation are the primary levers for extending battery life.

Adaptive power control, where the radio adjusts transmit power based on measured link quality, can significantly reduce average power consumption without degrading link reliability. This is relevant both for sensor nodes on fixed power budgets and for vehicle-mounted systems where generator load has operational implications.

Interference and Co-location Constraints

Defence platforms frequently co-locate multiple radio systems in a confined space. A patrol vehicle might carry VHF, UHF, HF, and GPS receivers within metres of each other. As outlined in our post on EMI and EMC in defence electronics, co-location creates reciprocal desensitisation, harmonic interference, and intermodulation distortion risks that must be addressed through frequency planning, physical separation, shielding, and filtering.

Antenna placement is particularly critical. Co-located antennas on vehicle rooflines require careful frequency separation analysis and, in some cases, antenna switching to reduce simultaneous transmit interference. The emergence of RFDEW systems adds a further co-location consideration: high-power microwave emissions from RFDEW platforms operating nearby represent a new category of unintended electromagnetic environment that standard EMC analysis does not currently model.

Procurement and Security Considerations for UK Defence Programmes

DSM Authorisation, DEF STAN Compliance, and DEMA Engagement

Radio equipment used in UK defence programmes must navigate two parallel compliance pathways. The first is spectrum authorisation: all spectrum-dependent equipment must be registered with DEMA and receive approval before deployment under Crown Use. This process should begin at programme initiation, as DEMA approval gates are embedded in the MoD’s acquisition framework under JSP 604. The second is electromagnetic compatibility compliance with DEF STAN 59-41, and, where applicable, type approval from the relevant equipment authority. Both processes are time-consuming and resource-intensive; neither should be treated as a final-stage activity.

Security Classifications and TEMPEST

Radios processing or transmitting classified information must comply with NCSC-approved COMSEC requirements. Where hardware emits compromising emanations (unintentional RF emissions that could be intercepted to reconstruct processed information), TEMPEST protection standards apply. TEMPEST certification is a specialist discipline and requires engagement with certified TEMPEST test facilities; it is not covered by standard EMC testing.

Supply Chain Security and Export Controls

The supply chain for defence RF components is subject to scrutiny from both a security and a strategic autonomy perspective. US-origin components incorporating ITAR-controlled technology require export licences for supply to non-US entities, including UK prime contractors on some programmes. UK-developed alternatives are preferred in classified programmes where technology transfer is not possible.

The UK government’s National Security and Investment Act 2021 has increased oversight of acquisitions involving sensitive technologies, including advanced radio and communications hardware. Programme managers and procurement leads should factor in the additional due diligence requirements this creates for supplier onboarding. The domestic industrial footprint of programmes like the RFDEW (which supports around 135 skilled jobs in Northern Ireland and Essex) is a deliberate policy objective, and the Defence Industrial Strategy reflects a continued preference for sovereign capability in high-risk RF technologies.

Final Thoughts: Designing for a Defence RF Landscape That’s Still Changing

Radio selection for defence deployments has never been a straightforward engineering decision, but the current period is more complex than most. The UK’s tactical communications infrastructure is in a state of genuine transition: Bowman is being extended beyond its intended service life, Morpheus is delayed by years with no confirmed in-service date, and the gap is being filled by a combination of upgraded legacy hardware and commercially proven MANET platforms procured on an accelerated basis. Hardware developers and procurement teams designing systems today need to be honest about which of those environments their equipment will actually interface with, because the answer shapes antenna design, waveform compatibility, DEMA authorisation scope, and through-life support strategy in ways that cannot easily be unpicked later.

At the same time, the RF threat environment is evolving in ways that existing design frameworks do not fully address. The successful field trials of the UK’s RFDEW demonstrator in 2024 and 2025 mark a genuine operational threshold: RF is no longer just a medium for communication; it is becoming a weapon in its own right. For engineers designing communication hardware for platforms that may operate in proximity to directed energy systems, this creates a new category of survivability requirement that sits outside current DEF STAN EMC testing and will need to be addressed as the technology matures toward operational service.

None of this makes the fundamental engineering discipline any less important. Frequency agility, power budgeting, LPI/LPD design, co-location analysis, and security architecture remain the foundation of any credible defence RF system. What changes is the context in which those decisions are made, and the need to design with enough flexibility to absorb requirements that will continue to shift as the UK’s tactical communications programmes resolve and as directed energy becomes part of the operational baseline.

The posts in this series are aimed at giving engineers and procurement leads a grounded view of the device development for the defence sector across topics such as sensors, UAVs, power design, EMC, and now radio selection. If any of these subjects raise questions specific to your programme, our team is well placed to help work through the details. Get in touch to discuss your defence system requirements.