Messaging and positioning in a dynamic TETRA environment

Abstract: Advanced communication with capabilities such as voice, data, and messaging usually requires an infrastructure with base stations, servers, and etcetera. The TETRA technology offers such communication not only in TMO (infrastructure-based network) but also in DMO where all nodes communicate directly (or via a repeater) with each other. This master’s thesis concerns messaging (specifically short messages) in a dynamic multi link TETRA DMO network. It examines what type of messaging technique to use and how to do path selection. The messages will be clear text, status, and GPS location information. The solution is implemented as a part of the ISIS software (which is developed by Know IT Dataunit). The planned multi link-part of the thesis could not be tested, so there is no implementation or evaluation of this. The evaluation of the implementation concerning sending and reception of messages shows that the proposed solution fulfils the demands for this kind of product. During a four day long test, messages (short text messages and positioning messages) were sent and received while a normal number of voice conversations took place, without packet loss.