DMR Digital Mobile Radio was a prominent theme at the recent PMRExpo in Germany, with established manufacturers and newcomers unveiling hardware and product plans at the show.

Several of these were based on Tier III of the DMR standard, which adds trunking and networking capabilities to the DMR system’s basic communications functions, and is therefore of special interest to users and potential users of larger radio systems.

Staged in Cologne, PMRExpo 2011 included two colloquium days, a conference on command and control centres, an applications forum and a three-day trade show attended by over 190 exhibitors. Dates for the 2012 event are November 22–24.

HARMONIZING RADIO IN THE WORKPLACE

Featured on the Motorola Solutions stand was the Total Enterprise Access and Mobility (Team) radio system – a converged voice communication package for the workplace.

“The whole idea behind the team solution is to create a force communication between different devices, from two-way radio to mobile computers (PDAs) running on a Wi-Fi network to this little device”, says Patrick Groot Nuelend. “It’s a team badge, a Wi-Fi-enabled push-to-talk device. This talks through the Wi-Fi network.”

Other devices which can access the system include Apple and Android smartphones, for which Motorola offers a voice client app. “It’s a harmonization platform which kind of brings in every possible voice client on to one platform”, Mr Nuelend explains.

To put the system through its paces, he next picks up a normal MotoTrbo two-way radio. An employee such as a security guard in a retail store might carry one of these – and, communicating, via a central Enterprise Server, could instantly contact the store manager on his smartphone or shop-floor staff via their Wi-Fi badges.

“Our primary market is retail – store associates, for example”, Mr Nuelend comments. “But also hospitality, warehousing, manufacturing. It’s a very easy to use, with a small device; cost-effective, so it doesn’t cost you a lot of money to implement.”

DIGITAL RADIO SYSTEMS FOR BUSINESS-CRITICAL APPLICATIONS

Tait, which outlined its plans for DMR at the recent FCS business radio day, had more to say at PMRExpo about its coming infrastructure and terminal products, which it expects to have ready for deployment around September this year. They will include high-performance base stations and repeaters, portables and mobiles, data modules, routers, networking equipment, applications and services.

“DMR Tier III is the latest digital technology defined specifically for business-critical applications”, said Jürgen Hörauf, of Tait Europe, who presented a conference paper at the conference on the advantages of Tier III technology.

“A modern, scalable communications system, which supports data and voice, DMR provides an ideal platform for digital business communications. Tait DMR solutions offer integrated location services, data services, over-the-air programming, network management, encryption and security features, with a stress-free migration path.”

Upgrade path

Some details of Tait’s plans were given by Jamie Bishop, regional marketing manager. “It uses our TB8100 base station platform”, he explained. “By changing the exciter in there and keeping the PA and the power management unit, there will be a migration from our existing base station to DMR Tier III.”

This, he said, was the kind of migration path the company’s major customers were looking for. “It’s changing one module in the base station and upgrading the node software. The advantage is that all of the control and channel management is going to be within that exciter module.

“It is quite clearly reducing the amount of equipment they will have to have on-site and therefore reducing the amount of potential failures you can have in individual control cards or channel management cards, as well as giving you all of the standard benefits of having a TDMA digital system.”

And all this was in addition to the basic advantages of DMR, including the ability to retain the existing antenna and combining equipment at each radio site.

“It’s quite a nice migration path, especially because of the terminals, which are also migratable”, Mr Bishop added. “The product that we release will be able to do MPT 1327, analogue and DMR Tier III; and that’s not a firmware upgrade but it will literally go into a software function. You can switch modes on the radio, and the radio can also scan between different networks.

“So if you wanted to migrate some of your radio network to DMR and keep some MPT, for some reason... then it will be entirely possible to have a hybrid network.”

Interoperable DMR
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