Wireless Communications Blog
DMR vs TETRA vs Push-to-Talk over Cellular: Which Technology Is Right for Your Organisation?
If you are evaluating digital two-way radio for your organisation, you will encounter three dominant technology options: DMR (Digital Mobile Radio), TETRA (Terrestrial Trunked Radio), and PoC (Push-to-Talk over Cellular). All three deliver digital voice communications. All three are an improvement on analogue. But they are built on fundamentally different architectures, serve different operational profiles, and carry very different cost and security implications.
This is a practical comparison aimed at communications managers, operations teams, and anyone responsible for specifying a radio system rather than just buying one.
The short version
If you want clarity before the detail: DMR is the practical choice for most commercial and industrial organisations. TETRA is the professional-grade option for demanding operational environments. PoC is compelling on paper but compromised in practice for mission-critical use. The rest of this article explains why.
DMR — Digital Mobile Radio
DMR is an open digital radio standard governed by ETSI. It was designed to be the digital successor to conventional analogue PMR (Private Mobile Radio) and has largely succeeded in that role. Most two-way radios sold in the UK commercial market today are DMR.
How it works
DMR uses TDMA (Time Division Multiple Access) to fit two simultaneous voice channels into a single 12.5 kHz radio channel — effectively doubling channel capacity compared to analogue. Radios operate either in a conventional (repeater or direct) configuration or, for larger systems, in a trunked configuration (DMR Tier III).
Where DMR works well
- Construction, logistics and utilities: The majority of UK commercial and industrial radio deployments. DMR is well understood, widely supported, and manufacturer-independent.
- Sites with existing analogue infrastructure: DMR equipment can often work in mixed analogue/digital mode during a transition period.
- Budget-conscious operations: DMR handsets and infrastructure are significantly cheaper than TETRA, with a wide choice of manufacturers including Motorola Solutions, Hytera, and Kenwood.
- Sites requiring encryption: DMR supports AES 256-bit encryption, though it must be correctly configured — many deployments leave encryption disabled.
Where DMR has limitations
- Large, complex trunked networks: DMR Tier III trunking exists but is less mature than TETRA trunking. Very large organisations with complex group structures often find TETRA more capable.
- Mission-critical public safety: TETRA’s priority and preemption features, late entry to call, and air-interface encryption are designed specifically for emergency services. DMR is not.
- Coverage without infrastructure: DMR requires repeater infrastructure or direct mode. It doesn’t route calls over a wide-area network without significant infrastructure investment.
TETRA — Terrestrial Trunked Radio
TETRA is a professional-grade digital trunked radio standard, also governed by ETSI, developed specifically for demanding operational and emergency service environments. In the UK, TETRA is the technology behind the Airwave network used by emergency services, and is widely deployed in rail, utilities, and large transport operations.
How it works
TETRA uses TDMA with four time slots per 25 kHz channel. It operates as a trunked network, dynamically allocating channels to calls. TETRA provides native air-interface encryption (TEA algorithms), meaning all transmissions are encrypted end-to-end without additional configuration.
Where TETRA works well
- Emergency services and critical national infrastructure: Priority calls, pre-emption of lower-priority calls, and resilience during network congestion are native features.
- Large, geographically dispersed operations: Rail networks, airport operations, large utilities, and port authorities.
- Environments requiring certified air-interface encryption: TETRA’s TEA encryption is certified and enabled by default.
- Data applications: TETRA supports data transmission natively, without the workarounds required on DMR.
Where TETRA has limitations
- Cost: TETRA infrastructure and handsets are substantially more expensive than DMR.
- Ecosystem: Fewer manufacturers, fewer form factors, higher device costs.
- Overkill for straightforward commercial operations: A warehousing operation, events company, or construction site does not need TETRA.
PoC — Push-to-Talk over Cellular
PoC uses a mobile data network (4G LTE or 5G) to deliver push-to-talk voice communications through a smartphone app or a specialist PoC handset. The radio is effectively an application running over a cellular network rather than a dedicated radio infrastructure.
Where PoC is genuinely attractive
- Nationwide or international coverage: Wherever there is cellular signal, coverage exists — without dedicated repeater infrastructure.
- Low upfront infrastructure cost: No repeaters, no base stations.
- Integration with other applications: GPS tracking, lone worker protection, dispatch software.
Where PoC creates problems
Network dependency. PoC is entirely dependent on commercial cellular network availability. In a major incident — precisely when radio communications are most critical — commercial networks experience congestion and may become unavailable. A licensed radio system with dedicated infrastructure is unaffected.
Latency. Push-to-talk latency over cellular (typically 300–500ms, sometimes higher) is noticeably worse than a local radio network (typically under 100ms). In operational environments, this delay is consistently noticed.
Coverage gaps. Underground, in basements, in metal-frame buildings, and in rural areas, cellular coverage is patchy. Many industrial sites have coverage gaps that a local repeater system would not have.
Security and compliance. PoC traffic passes through a third-party cloud platform. For organisations with IEC 62443 compliance obligations or data protection requirements, transmitting operational communications via a commercial cloud platform raises questions that a private radio network does not.
Battery life. PoC handsets running continuous data connections consume significantly more power than conventional radio terminals.
Side-by-side comparison
| DMR | TETRA | PoC | |
|---|---|---|---|
| Coverage model | Local infrastructure | Local infrastructure | Cellular network |
| Air-interface encryption | Optional (AES 256 if configured) | Native (TEA, always on) | Platform-dependent |
| Latency | Low (<100ms) | Low (<100ms) | Higher (300–500ms+) |
| Infrastructure cost | Moderate | High | Low |
| Handset cost | Low–moderate | High | Low–moderate |
| Network resilience | High (independent) | Very high | Dependent on MNO |
| IEC 62443 considerations | Must configure encryption; zone mapping required | Encryption native; zone assessment still required | Cloud dependency; data sovereignty concerns |
The question that often gets skipped
Most organisations focus on coverage, handset cost, and features when evaluating radio technology. The question that is less often asked is: how secure is the radio network, and who has assessed that?
DMR systems are frequently deployed with encryption disabled or incorrectly configured, talkgroups accessible to anyone with a compatible radio, and SCADA telemetry links that were never assessed. TETRA systems have native encryption, but even TETRA deployments can have zone boundary issues. PoC creates an entirely different set of questions around data sovereignty that most organisations haven’t worked through.
If your organisation operates under IEC 62443, NIS2, or the UK Cyber Security and Resilience Bill requirements, the technology choice is only part of the answer. The other part is whether the radio system has been properly assessed as a communications conduit — regardless of which technology sits underneath it.
Making the decision
For most UK commercial and industrial organisations, DMR is the right starting point — cost-effective, manufacturer-independent, and well-supported. TETRA is the right choice when you need trunking at scale, mission-critical resilience, and native encryption. PoC is most useful as a supplement for users who genuinely need nationwide coverage, rather than a primary system for demanding environments.
If you need independent advice on which technology fits your operational profile, or want a review of an existing system, Yesway’s technical consultancy service starts with the requirement, not the product.
Craig Miles is a wireless communications engineer with 30 years of RF and radio systems experience, including aerospace satellite systems at Airbus Defence & Space. He is a PGCE Level 7 qualified engineer and 2023 TEDx speaker. Yesway Communications is manufacturer-independent and advises across DMR, TETRA, and PoC technologies.
