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This wireless addition to the company’s Aurelis series incorporates a push-to-talk button, a microphone, high-quality speakers, an emergency button, a three-level volume control, two-colour LED and expansion potential for connecting external audio devices. “The possibilities with our new Aurelis series give the user in task forces and security agencies the optimal use of the digital radios”, said Mathias Iser, the company’s technical director. Machine-to-machine TETRAPossibly the company which had the shortest journey to make to the exhibition hall was Funk-Electronic Piciorgros, of Cologne, a specialist in radio modems and telemetry products for control and monitoring applications using GSM and TETRA. Latest innovation from the company is a compact TETRA radio card, developed in-house. “This makes us independent from others, because we started with external modems and we fixed some bugs and we did research for them”, explained r&d engineer Dirk Reufsteck. “But we wanted to have it in our own hands, so now we have the knowledge, we have the product. If we have to change something, we can do it on our own – we don’t have to ask whoever.” One such development Piciorgros has already implemented is a simplified alternative to some of the rather complex command language used for controlling radio modems – for example, for the common requirement of initiating a packet data transfer. “We said, why is it that complicated? It’s just to enable packet data, that’s it. And so we made a command to enable packet data. And then our modem gets this command and it enables packet data. And that’s everything.” Another problem solved by the board, he said, is that some TETRA base stations are apt to ‘forget’ telemetry devices after 30 minutes if they do not transmit frequently. “We had this problem and we solved it with implementing in our TETRA stack to send a packet to the base station. So maybe we fixed some base station bugs! We recognized it, and it was half a day!” Connecting with the networkGerman mobile data specialist Hagedorn Informationssysteme showed a variety of hardware and software-based tools, applications and interfacing device for TETRA installations. Among these was a voice-over-IP server which interfaces the TETRA system to the IP world and vice versa , acting as a TETRA media gateway to a LAN. Certain analogue radio models can be connected to it too. “The information that we get from these devices, we transfer into the IP, and on the other side we are catching all information with our dispatcher, our hardware or software clients”, explained Ivan Kosko, at a rack of equipment. “The most simple one is an IP radio speaker which can get only information from one radio – it has only one PTT, one microphone, one speaker. Then the more complicated one is an IP console unit. “With this console you can switch between the radios which currently you want to control.... So you can navigate and control the radio as if you were sitting directly on it. “The most sophisticated is an IP dispatcher unit. To it you can connect many more accessories.... You can switch the display between the radios. You can have up to four PTTs. Then you can have two separate streams, so you can have mixed groups in one speaker and in [the other], for instance, individual calls.” Supporting the hardware are the company’s desktop dispatcher applications. “The most simple one is a virtual radio which is connected to the one radio”, Mr Kosko continued. “You are getting the voice and data, as if you are behind the radio. Then we have, more complicated, the virtual console. You can have at the same time up to eight devices so you can directly decide over which device you want to speak. You just press PTT and speak.” Making the most of multi-slot data when network loading is heavyFrench infrastructure developer Etelm is working on new equipment to introduce in May at the TETRA World Congress in Dubai – but in the meantime it was showing its GPSy indoor positioning system, which relies on fixed radio beacons, and its NeTIS TETRA base station range. “We have a large success because of the design and of the capability of this equipment and now we deliver a lot”, said Pierre Minot, president of Etelm, speaking of the base station. “We are improving the capabilities of it. We have been working a lot with multi-slot packet data because multi-slot packet data is difficult when you want to optimize. “What is important in multi-slot packet data is to provide intensive tests with a lot of traffic, because most of the problems with this technology are when the traffic increases near to the overload point. And so now we are supplying a function which is proved with a lot of traffic. We have spent a lot of time, three months of tests, with simulations and real-time tests, to be sure of this solution without any blocking effects.”
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