Tools FAQ

The following list of Questions and Answers has been compiled to provide quick guidance on the characterization of Tools managed by the GSTI portal as well as general explanations on GNSS simulation and testing.

What is a GNSS RF Generator?

A RF GNSS Signal Generator (or simulator) is an equipment recreating the RF signal(s) broadcasted by satellite(s). RF GNSS Signal Generators can simulate several type of environment faced by GNSS receivers such as multipath, urban canyon,... One of the main objectives of such tools is to enable the testing  of the whole GNSS receiver’s chain in the laboratory.

What is a software signal generator?

A software signal generator is a software tool capable of simulating or modelling:

- GNSS signals,

- GNSS signals propagation and corresponding environmental effects (ionosphere, troposphere, multipath, etc.)

- GNSS signals processing by a configurable GNSS receiver.

Software Signal Generator is useful for testing GNSS receiver algorithm during the design phases.

What is a GNSS Field test bed?

A GNSS Field Test Bed is a ground-based infrastructure enabling the test of GNSS equipment (receivers, antennas etc.) or applications under representative real field conditions.

What is a software receiver?

A software receiver is a software tool potentially supported by hardware, simulating the behaviour of a GNSS receiver. Various parameters may be included to modify GNSS signals processed, algorithms implemented, etc. GNSS signals used at the input of these tools may take different forms, and can be considered at different level of the signal processing chain. These inputs may come from various sources (software generated; real digitalized GNSS signals, real time processed thanks to hardware front-end equipments etc.).

What is an anechoic chamber?

An anechoic chamber is a room designed to stop electromagnetic reflections wave. This kind of infrastructure is particularly useful to test antenna.

What is a signal recorder?

A GNSS Signals recorder is an equipment or facility dedicated to the acquisition and storage of real field GNSS signals for later use during the testing procedures.

What is a signal propagation simulator?

A signal propagation simulator is a tool simulating wave propagation (including reflexion, absorption…) in a modelling environment. This kind of tool is used to validate or design the algorithms used to mitigate the impact of environment at local (receiver) level.

What is a service volume simulator?

A GNSS service volume simulator is a tool or facility dedicated to the simulation and/or evaluation of performances achieved by GNSS constellations. Constellation simulation refers to satellite constellation definition and modelling. Performances to be assessed may include: service volume, DOP calculation, orbital parameters, time accuracy, ionosphere, troposphere, integrity, precision, etc.

What is a test bench for receivers?

Test bench tools are dedicated to the evaluation and benchmarking of receivers against performance criteria. They can be used during validation and quality control.

What is a Hardware receiver or front-end?

Hardware receiver is a whole GNSS receiver. Front-end is only the RF part of a GNSS receiver. This kind of equipment is useful to develop GNSS based application.

What is a reference network?

A reference network is a set of GNSS stations monitoring and recording GNSS data with high accuracy. The reference network provides reference data in real-time and/or for post-processing and is therefore useful to validate GNSS based applications.