DMR in the spotlight

It has taken over a decade for 15 per cent of the world’s licensed mobile radio users to switch from analogue to digital, according to a recent report (IMS Research). However, these key findings suggest that despite this sluggish start, recent developments within the industry are set to see migration more than double in the next five years.

Digital technologies were first introduced to the mobile radio market in the mid-1990s. Early standards included Tetra and APCO Project 25 (P25), but were designed for use by the emergency services and so, for many commercial organizations, they can be rather like using a sledgehammer to crack a nut.

While technologies such as dPMR, NXDN and PDT will help to open up the digital market to many more users, it is the introduction of Digital Mobile Radio (DMR) in particular that will fuel growth.

So what is DMR?

DMR is a two-slot, time division multiple access (TDMA) system offering voice, data and a range of other features and applications.

This is the same underlying technology used by Tetra and P25 Phase II. Simply put, TDMA divides up spectrum using timeslots (diagram, left): User A gets a few milliseconds of access to the bandwidth, and then it is User B’s turn.

• DMR Tier 1 is targeted at the unlicensed market, providing for consumer applications and low-power commercial applications.
• DMR Tier 2 is targeted at those who require spectral efficiency, advanced voice features and integrated IP data in licensed bands for high-power communications.
• DMR Tier 3 is the trunked variant of the standard, for systems with a large number of subscribers and for multi-site networks.

The standard’s primary goal is to specify a digital system offering low complexity, low cost and interoperability across manufacturers. What this means is that user organizations are not locked in to a proprietary solution.

An industry standard

Simoco is a committed member of the DMR Association and continues to be heavily involved in both the marketing and technical working groups. One of the key objectives of the association is to provide a mechanism for ensuring that DMR equipment from different manufacturers will interoperate.

By removing barriers to interoperability and supporting innovation and adoption, a single agreed standard enables end-use to buy with a greater degree of confidence. With dPMR, such a programme does not exist and so you find fewer manufacturers actually developing hardware.

Simoco’s commitment to DMR is reinforced by significant investment in both people and facilities. Its global research and development operations have been significantly expanded, increasing both head count and the size of its facilities in the UK and Australia. Simoco has al so created brand new hardware platforms for its DMR offering, to ensure state of the art designs that are future-proof.

Applying what we know

Simoco’s experience in developing and delivering MPT systems dates back to the creation of the open MPT standard. The company went on to deploy many systems around the world with its TN10X and RTSX trunked switching infrastructure. In 2005, Simoco reinforced its product credentials with the launch of the Xfin system, a fully distributed MPT infrastructure running on an IP backbone.

Xfin was the first MPT system to be deployable over an IP backbone and the first switchless technology to be used in MPT. Unparalleled in its ability to continue operating during fault conditions, it is the most resilient radio system in the world.

Simoco has enjoyed considerable success with its Xfin MPT trunked infrastructure. Installed systems range from single-site deployments to large networks in excess of 100 sites.

Building blocks for success

Simoco’s DMR infrastructure is based on the same successful design principles as Xfin. IP connectivity allows the radio system to sit on a backbone which delivers multiple routes between sites on the network, easing bandwidth and maximizing resilience.

Additional sites and applications, such as dispatchers and voice recorders, can be incorporated simply by connecting to the IP network. System support and maintenance can also be carried out remotely over the IP network; previously, expensive and time-consuming site visits would have been required in order to manage the network.

Simoco is one of only three independent suppliers manufacturing complete end-to-end DMR solutions which include a full portfolio of portables, mobiles, base stations and infrastructure.

Who will adopt DMR?

The short answer is everyone. With its all-embracing nature, DMR is suitable for all vertical markets. Already we are already seeing strong interest from sectors such as power and utilities, oil, gas and mining, as well as from small campus applications, all with diverse user requirements. The common requirement of all these customers is experienced equipment suppliers with strong systems integration experience across a range of applications.

Because DMR is a tiered technology with a common air interface, it can deliver systems that range in size and complexity. Simoco is developing DMR products in both Tier 2 and Tier 3, to provide full turn-key solutions. With its mobiles, portables, IP based distributed infrastructure and suite of applications, Simoco will offer system solutions for all users.

From the ground up

So let’s be clear: digital isn’t anything new. We all have cell phones, and some might question as to why professional radio has lagged so far behind. The short answer is that it hasn’t. Rather, the digital standards that emerged previously, such as P25 and Tetra (both of which were designed for emergency services) simply weren’t fit for purpose in the commercial world.

DMR has been designed from the ground up for users of professional mobile radio. It efficiently increases capacity, offers longer battery life and minimizes the use of infrastructure. The standard also facilitates advanced functionality and control features along with the use of business critical data applications. Finally DMR brings the clarity of digital voice.

DMR is a technology with all the good points of the mature technologies used by the emergency services, but is squarely aimed at the cost-sensitive commercial space.

SETTING THE STANDARDS IN MOBILE RADIO

Simoco has earned a global reputation in the radio communications industry for exceeding expectations by ensuring quality, innovation, performance and service.

With a heritage dating back 70 years to the birth of effective radio communication, Simoco continues to develop the highest quality, mission-critical, radio technologies for commercial, government, and public safety sectors worldwide.

From market leading conventional, trunked and simulcast systems to cutting-edge Tetra, P25 and DMR, Simoco has dedicated its r&d resources to the development, manufacture and integration of complete radio communications solutions: technology-agnostic, turnkey solutions tailored to meet specific and individual needs.

• www.teamsimoco.com

HOW CAN I BENEFIT FROM DMR?

Benefits of moving to DMR can be summed up as follows:

• Twice the channel capacity: with DMR, a single 12∙5 kHz channel can support two simultaneous and independent calls. This is achieved using TDMA.
•  Compatibility with legacy analogue systems: this will be of benefit if (for example) you need to retain existing legacy radios or to work with external organizations which still use analogue handsets.
• Efficient use of equipment: another advantage of the DMR TDMA approach is that you gain two communications channels with one repeater, one antenna and a simple duplexer.
• Greater power efficiency: until now there have been few options for increasing talk time on portable radios on a single charge. In two-slot, TDMA however, the portable transmits for only half of the time compared with an analogue radio, thus increasing battery life.
• Ease of use and creation of data applications: the end-to-end nature of DMR means that applications such as text messaging, GPS and telemetry can be added on to radio devices and systems with a minimum of fuss. In addition, with support for transmitting IP data over the air it is possible to develop standard applications.
• A well-established, widely backed standard: as an open standard backed by a wide variety of vendors, DMR assures end-user organizations of continuity of supply through the lifespan of their network.

Source: landmobile.co.uk