dPMR Mode 1 forms the basis for all forms of licenced PMR use and is part of the ETSI standard TS102 658.
dPMR Mode 1 is part of the ETSI standard TS102 658 and the basis for the application of dPMR across all forms of licenced PMR use.
dPMR Mode 1 offers the benefits of FDMA 6.25 kHz narrowband spectral efficiency in licensed operations for peer-to-peer communication in voice and data where repeaters and infrastructure are not a requirement.
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.
FDMA & TDMA in peer-to-peer communication
In simple terms. dPMR Mode 1 can be considered as an advanced version of dPMR446 as it offers higher powered equipment in both hand-portable (1 – 5 watts RF output) and mobile formats (5 – 25 watts RF output) which in turn, deliver significantly increased coverage over license-free dPMR 446 (0.5 watts RF output).
dPMR Mode 1 provides an easily implemented two-way radio communication system for applications where local area coverage is required. Base station (non-repeater type) radios can be employed and interconnected to IT networks via IP to exploit both text messaging and voice calls using the voice and data functionality of dPMR. In addition to offering voice and data capabilities, dPMR446 Mode 1 also supports combined voice + data, making it is possible to embed data into a voice call or automatically append it at the end of a call.
With the removal of the limitations of PMR 446 licence-free operation, dPMR Mode 1 can offer more advanced features and user safety functions including GPS, priority, emergency and call break-in.
Mode 1 Operation
dPMR Mode 1 Equipment
dPMR is an ‘open standard’ which promotes choice by encouraging competing manufacturers to development equipment meeting with dPMR ETSI standards. As with all dPMR Modes, equipment complying with dPMR Mode 1 is backward compatible with legacy analogue equipment and
can operate in both FM analogue and dPMR digital modes giving users a logical and cost effective pathway in the migration from analogue systems to the benefits of digital technology.
Current equipment complying with ETSI standard TS102 658 for operation in dPMR Mode 1 includes hand-portables, mobiles, base stations, modems and repeaters and hand-portable radios meeting with IEC Ex/ATEX based IS/ specifications for use in explosive atmospheres in the oil, mining and chemical industries.