dPMR: a brief overview

digital Private Mobile Radio (dPMR) delivers a spectrum efficient, low cost, low complexity, high functionality digital radio communication solution across many forms of voice and/or data applications; from license-free dPMR 446 to fully scalable trunked networks.


With ever increasing demand on the radio spectrum and the limited number of frequencies available, the need for efficient technologies that maximise the utility of those frequencies has never been greater.

dPMR is a spectrum efficient, true 6.25kHz ‘ultra-narrowband’ digital radio communications technology for application in Private Mobile Radio (PMR). It was developed by the European Telecommunications Standards Institute (ETSI) in 2007 to specifically target highly functional, spectrum efficient solutions employing proven, low cost and low complexity Frequency-Division Multiple Access (FDMA) technology to meet future regulatory requirements for 6.25kHz channel equivalence.

The three broad categories in which dPMR has the capability to serve are:
(1) Consumer and short-range industrial applications
(2) Professional/Business/Operations-Critical applications
(3) Public Safety/Mission-Critical applications.

dPMR is developed in ‘tiers’ to offer a scalable communication solution that includes license-free dPMR 446 mode (in a 446.1 to 446.2 MHz band) and licensed modes subject to national frequency planning:
• Tier 1 is the low-cost, licence-exempt 'digital PMR446' defined by ETSI Technical Specification TS 102 490.
• Tier 2 is for the licensed professional market, offering peer-to-peer mode (Mode 1), repeater mode (Mode 2) and trunked (managed access) operation (Mode 3). Tier 2 is defined by ETSI Technical Specification TS 102 658.

These ‘Tiers’ are sub-divided into four functional levels:

dPMR 446:

dPMR 446 is a licence-free two-way radio communication format for use in peer-to-peer operations without base stations or repeaters in the 446 MHz UHF band. This technology is covered by the ETSI standard TS102 490.

Mode 1:

dPMR Mode 1 forms the basis for all forms of licenced PMR use and is part of the ETSI standard TS102 658.

Mode 2:

PMR Mode 2 is the licenced conventional PMR version that includes all base station and repeater functionality and allows interfaces via gateways (Telephone, IP etc.) and is part of the ETSI standard TS102 658.

Mode 3:

dPMR Mode 3 is part of the ETSI standard TS102 658 and offers managed access, multi-site trunked systems and systems where the full functionality of the protocol is available.


dPMR™ Product Class Interoperability

To assist users in the selection of appropriate dPMR products and solutions for specific applications, the dPMR Association has introduced Product Classes to distinguish between the compatibility and capabilities of different dPMR compliant equipment. Full details can be found here, but potential users are warned that equipment offered for sale which has not been tested to the satisfaction of the dPMR Association Technical Working Group and Certified for compliance with all relevant parts of the ETSI conformance and interoperability standards for dPMR are unlikely to meet with ETSI standards or offer interoperability with compliant dPMR marked equipment in any of the dPMR Product Classes.

Promoting choice and best value

dPMR is an open standard supported by number of equipment manufacturers, specialist technology companies and software developers which promotes a dynamic competitive environment resulting in greater choice and lower costs to the end-user. The dPMR Association actively encourages the adoption of the standard and makes no charge or licensing fee for its IPR save that all equipment designed for use with the technology or carrying the dPMR mark are certified as compliant through the dPMR testing and certification programme.

dPMR, the logical and cost effective pathway from analogue to digital

All dPMR functional levels and Modes are backward compatible with legacy analogue radio systems and equipment which makes it the logical choice when evolving a radio system from analogue to digital at a pace that suits operational requirements or budget constraints. Equipment certified as compliant with dPMR will feature Analogue FM – Digital dPMR mixed mode operation either activated automatically or through user selection so seamless communication between old and new can be maintained throughout the transitional period.

Migrate from analogue MPT 1327 to dPMR with ease

For existing users of MPT 1327 based trunked radio systems, dPMR Mode 3 offers an immediate and cost-effective migration path to digital without compromising on functionality or system features.

FDMA v TDMA

Unlike the TDMA (Time Division Multiple Access) method which divides a 12.5kHz channel into two alternating 30msec timeslots to achieve 6.25kHz equivalence, the FDMA (Frequency Division Access) method employed by dPMR divides the same 12.5kHz channel in length, creating two identical 6.25kHz channels, allowing users to effectively double the capacity of their usable spectrum without the need for a repeater to synchronise time slots. This is especially important in ensuring the availability of communication in critical situations when there is increased demand on an allocated radio spectrum. Both channel access methods offer distinct features and benefits and the choice between the two should ultimately be made based on its suitability for the end use application.




dPMR is Feature Rich...

Contrary to what you might have heard or read, while the dPMR standard is based on using low cost and low complexity technology in a simple, rapidly deployable format; it certainly does not lack the full range of functionality demanded by today’s radio communication users in commercial, operations and mission critical applications. The table below highlights some of the advantages dPMR can bring in meeting your communications needs either through the inherent functional attributes of the technology or manufacturer specific features. To ensure you arrive at the ideal dPMR solution for your specific application, contact your reseller or system integration partner or email support@dpmr-mou.org giving an outline of what you want to achieve.

Features - Systems & Subscribers dPMR 446  Mode 1  Mode 2   Mode 3
License Free 446MHz
Licensed Frequencies
Peer to Peer mode without repeaters
Small user systems and/or low traffic density
Large user system for high call density
Repeaters and infrastructure
Up to 32 channels per site
Up to 16 site multi-site trunking
Up to 256 site multi-site trunking
Wide area system using IP connectivity
Web based system administration
Up to 500,0000 subscribers
Individual Calls
Group Call
Broadcast Call
Radio to all users calls
AMBE+2 Vocoder for Natural Sounding Digital Voice
Short Data Message (SDM)
Status Call
Telemetry or Data Applications
GPS Data Delivery
Applications Interface (line connected)
Emergency Call & Alert
Pre-emptive Emergency
Ambience Listening
Remote Kill/Stun/Revive
Call Queue
Digital Voice Scrambler
Late Entry to Group Call
Automatic Call Set-up
Man Down Alerting
Lone Worker Functionality

Membership

A Community

Our community is represented by some of the most important companies in global radio communications and is open to any manufacturer, supplier, user group, administration, laboratory, integrators and resellers.

Growing our Reach

dPMR’s growing community includes the end user; the most important contributor to the success of the technology.

An ETSI compliant open standard

dPMR is compliant with ERM dPMR standards as specified in ETSI TS 102 490 and TS102 658 (6.25 kHz FDMA standard set). As an open standard, the dPMR Association actively encourages the adoption of the technology and makes no charge or licensing fee for its IPR.

Questions? Feel free to get in touch ...

Membership info or technical data and all else in between; we're happy to answer your queries ...

About us

The dPMR Association was established in 2007 and provides a forum for interested parties to contribute their expertise.

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