Integrated GNSS and Mobile Communication Terminal - NAVCOM

Status date

The objective of NAVCOM is the development and demonstration of an Integrated Navigation / Mobile Communication User Terminal based on the TETRAPOL system. TETRAPOL is a fully-secured-digital solution designed to meet the growing needs and expectations of highly-demanding Professional Mobile Radio (PMR) users such as public safety forces, transport, or industry. In the context of these applications, the user requirements have been defined in terms of equipment features (size, low-power, low-cost, etc) and the quality of service (accuracy, service availability, frequency of location update, etc).

A GPS/EGNOS receiver has been integrated in and assisted by the communication terminal of TETRAPOL. The European Geostationary Navigation Overlay Service (EGNOS) is used to improve and augment the service of the satellite navigation system GPS. The implementation of the GPS/EGNOS receiver is characterised by the design, simulation, prototyping, verification, and testing of all analog and digital components.

A subsequent demonstration phase verifies the performance of the system in the field of tracking mobile targets to supply security and emergency applications with an Automatic Vehicle Localization (AVL) system.

The key issues of the Integrated GNSS and Mobile Communication Terminal project are:

  • Design and prototyping of a GPS/EGNOS module,

  • Integration of the navigation module into the communication system,

  • Provision of valorised position information to an AVL system,

  • Demonstration of the system benefits for safety and security applications (especially accuracy improvement due to EGNOS).

Demonstration Test Results

The demonstration tests are carried out mainly to point out the benefit of EGNOS regarding the improvement of the absolute positioning accuracy. Thus, combined GPS/EGNOS positioning is compared to GPS stand alone positioning. The reference is generated by a geodetic GPS receiver with an absolute accuracy of about 2-5 cm. Additionally, the position messages are transferred to the AVL server at EADS by using the TETRAPOL communication link. Thus, on the display of the AVL server, the location of the measurement vehicle can be visualized and the trajectory points are stored in a database.

The tests show clearly the significantly improved positioning accuracy of combined GPS/EGNOS positioning and that nearly hundred percent of the generated position messages are received at the AVL server. Only if the communication link is shadowed (e.g. due to interferences, etc.), the generated position messages are not transmitted to the AVL server.

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The objective of this project is to develop and demonstrate an Integrated navigation/Mobile Communication User Terminal based on the TETRAPOL system.

Therefore the system will provide:

  • Positioning capability,

  • Communication capability,

  • The exploitation of functional synergies of communication and navigation,

  • Increasing performances regarding the navigation requirements (availability, acquisition, etc).

As a consequence the potential benefits of the system are:

  • Display the position (actual and previous) of the mobile resources on a digital map,

  • Display velocity and heading information,

  • Provide a tool for route guidance / traffic management,

  • Provide a tool to allocate resources to operation areas / events (resource management),

  • Provide a communication link with other mobile resources allocated to the same area / event,

  • Provide a communication link to the mobile and other (hospitals,&) resources for voice and data transmission,

  • Provide a data archive to record data and voice transmissions.

These benefits fulfil the requirements of Security / Police, Search / Rescue and Emergency Call (E 112) applications. The overall key benefit will be increased security and safety.

The main task of the NAVCOM project is the integration of a GPS/EGNOS receiver into an existing TETRAPOL mobile communication unit. This Integrated Terminal will supply the actual and valorised position information via the TETRAPOL communication network to an AVL Server. A user is able to track and guide several IT's on an AVL display and communicate with them via the voice and data channel of the TETRAPOL system. The navigation module is able to acquire assisted GPS and assisted EGNOS information via the communication system in case that the clear view to the satellites is obstructed.

The communication part of the project is under the responsibility of EADS Telecom, whereas the navigation part is implemented by IMST, Fraunhofer and IFEN. TeleConsult is responsible for the demonstration phase.

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Phase 1: Setting the Requirements:

Phase 1 of the NAVCOM project started with the definition and identification of the requirements of the applications Security / Police, Search / Rescue and Emergency Call (E 112) regarding an integrated navigation - mobile communication system. In the sequel the Integrated Terminal was defined and the requirement onto a GNSS/EGNOS receiver module settled. During the review meeting the specifications for the integrated navigation / communication user terminal were formally agreed.

Phase 2: Prototype Development and Demonstrations:

Phase 2 started with the detailed design of the integrated navigation / mobile communication terminal and in particular of the GNSS/EGNOS receiver module. Moreover, it included the design of any facility or ancillary equipment as needed for the Integrated Terminal, at the communications end or for the field demonstration programme. After a critical design review the prototyping of the Integrated Terminal preceded acceptance tests of the integrated system. At the end of phase two the project team implements and executes the application demonstration and the dissemination plan. The demonstration programme concludes with a critical assessment of the effectiveness of the Integrated Terminal especially regarding the improved positioning accuracy.
Current status

Phase 1 and Phase 2 have been completed successfully. The project was closed in course of the Final Review in October 2007.