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    25 Oct 2014 
ARTES Elements
Tenders and Workplans
Last Update: 10 Aug 2007

NAVIndoor 2



Space Systems Finland has studied a technique with an aim of developing a navigation system that extends the usage of satellite based positioning methods into environments where the GNSS signal is either weak or not at all available. SSF has built a prototype navigation system consisting of synchronised pseudolites (pseudo satellites).

The objectives of the current project are

  • to perform a technical feasibility assessment that includes identification of critical requirements, upgrades to the prototype system, production planning for a commercial roll-out and conduction of a pilot project.
  • to perform a commercial feasibility assessment.


The NAVIndoor system contains a stationary part that generates navigation signals, and a mobile part that is used to receive these signals and to provide position information to the user.

The stationary part of the system consists of:

  • Several pseudolites sending a GPS compatible signal at the GPS frequency containing the navigation data. All pseudolites in the system are synchronised.
  • Reference receivers used to monitor the signals sent by the pseudolites.
  • A master control station controlling the operation of the pseudolites. The master control station uses the output of the reference receivers for the integrity monitoring of the pseudolite signals and in the synchronisation of the pseudolite clocks.
The mobile part of the system consists of GPS receivers and an application that utilizes the location information provided by the receiver.

The NAVIndoor system can be used either as a standalone navigation system, i.e. with no connection to GPS navigation, or by using GPS signal e.g. as a means of synchronising the pseudolites. The NAVIndoor can also be used as a local component to GPS, in order to improve satellite navigation in places with low GPS signal.

Project Plan

The project is divided into three major subtasks. These are:

  • Technical feasibility analysis,
  • Pilot installation with a public demonstration
  • Commercial analysis.
The project kick-off was held in the spring of 2003 and the project will end in the spring of 2004.


The project develops a navigation system consisting of synchronised pseudolites. The system can be used as a stand-alone system or as a complement to the existing GNSS methods. The system aims to provide a position determination that can be used in areas where GNSS satellites can not be used, e.g. indoor environments.


The NAVIndoor system enables GNSS-like navigation in locations where the GNSS satellites can not provide a reliable solution. Indoor navigation is not only a promising market but also seen as an essential local area augmentation for GPS and Galileo.

The project seeks new markets for GNSS navigation solutions and hopes to attract the attention of new industrial customers. The system will also broaden the market for existing navigation solutions, as it will extend the possibilities of such systems.

Given the potential interactions with future Galileo signals the project will also provide an early attention to compatibility issues.

Current Status (dated: 30 Mar 2004)

The project was closed with a public demonstration at the Start-up Projects Initiative Workshop 2004 in the ESTEC facilities at the 22nd to 23rd of March 2004. The public demonstration generated a lot of very positive response.

During the project we have further developed the pseudolites into stable and usable hardware ready to be shipped in small series. We have proven the feasibility and usability of a synchronized pseudolite system in an outdoor environment. Further, we have proven the feasibility of such a system in an indoor environment. In the indoor environment we have shown that it is possible to identify, isolate and mitigate the multipath component from the pseudolite system. We have also shown how a dynamic rover is able to utilise a pseudolite system under these difficult multipath conditions.

With regards to Galileo we have started to evaluate the impact the Galileo signal specification will have on the current pseudolite design.

We have opened the commercialisation of the pseudolite infrastructure by starting the integration work together system integrators identified during the project.

Last Update: 10 Aug 2007
Project Plan
Current Status
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