& Product Classification Guide

The dPMR Interoperability (IOP) process is a documented test procedure conducted under controlled conditions which establishes the compatibility of equipment from different manufacturers to ensure products are compatible with each other when used in the same dPMR system.

dPMR is an open standard digital two way radio technology designed for a multi-vendor eco-system in which competing manufacturers develop and market equipment to suit user requirements but within a single set of standards. This gives users the choice of vendors, equipment and features which should be capable of working with each other on any other system employing equipment tested and certified to the same level. For instance, there may be a requirement in a single system for both standard hand-held and mobile radios to work alongside intrinsically safe or waterproofed models.

dPMR Association Interoperability (IOP) Documents

There are a number of international standards that radio manufacturers must comply with in order to qualify as being “dPMR compliant”. These are published by ETSI and developed and maintained by the TGDMR group, to which many dPMR Association members contribute on a regular basis. IOP testing is a collaborative process where manufacturers wishing to apply for IoP testing should first contact the dPMR Association secretary or the dPMR Technical Working Group (TWG) Chairman who will then co-ordinate with other members to establish a suitable time and place for the tests. IOP testing is open to both members and non-members of the dPMR Association, however, certificates can only be issued to members while non-members will receive a Test Report. Full details on the IOP process can be found here.

dPMR™ Product Class Interoperability

To assist users in the selection of appropriate dPMR digital two way radio products and solutions for specific applications, the dPMR Association have introduced Product Classes to distinguish between the compatibility and capabilities of different dPMR compliant equipment. This interoperability classification is principally required for TS 102 490 compliant equipment (e.g. for dPMR446), where different compliant Vocoders are permitted but will not inter-work with each other.

For equipment operating to ERM dPMR standards as specified in ETSI TS 102 658 in FDMA protocol with a channel spacing of 6.25 kHz (6.25 kHz FDMA standard set), the dPMR Association have standardised the AMBE+2 Vocoder, so users can be sure that any equipment which has passed interoperability (IOP) testing and granted an IOP Certificate or Test Report has the right to display the dPMR logo and will be interoperable with other equipment of the same Class.

In the cases of Class A (AMBE +2 Vocoder) and Class R (RALCWI Vocoder), equipment of the same Class will offer full interoperability irrespective of manufacturer, while combining the use of equipment from different classes could result in limited functions being available.

Class M equipment employ a manufacturer specific Vocoder and therefore Class M marking of a product serves as a warning to users that it may not work with any other class and, in addition, may not work with Class M equipment from another manufacturer.

Product classification marking of TS102 490 unlicensed dPMR 446 compliant equipment:

Classification Guide
Classification Vocoder Type Interoperability Product Marking
CLASS R RALCWI™ Vocoder Full interoperability with other Class R equipment.
Limited interoperability with other dPMR Classes.
CLASS A AMBE+2™ Vocoder Full interoperability with other Class A equipment.
Limited interoperability with other dPMR Classes.
CLASS M Manufacturer Specific
May not work with other Class M equipment.
May not work with other dPMR Classes.
Next, read about Functional Levels >

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


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