Multi-GNSS Simulation & Test Environment (MGSE)
MGSE creates a GNSS simulation environment that provides the possibility and flexibility to use: synthetically generated
data and recorded real-world samples – both exactly reproducible. MGSE considerably improves the development,
qualification, and certfication process of GNSS receivers within the development phases and during validation/certification
in end-to-end tests.
MGSE creates a GNSS simulation environment that consists of:
The MGSE integrated system will be composed of
- MGSE GIPSIE®: Synthetically generated data
The multi-frequency, multi-system software-based GNSS simulation environment GIPSIE® consists of two
modules – the satellite constellation simulator (SCS) and the intermediate frequency simulator (IFS). The MGSE
GIPSIE® simulation environment includes GPS, Galileo, GLONASS, BeiDou, QZSS, and IRNSS constellations and
generated IF signals.
- MGSE GTEC© Recording Unit: Received real-world GNSS data
Beside the multi-band GNSS antenna, the main objective of the multi-band RF front-end (GTEC© RFFE) is to
receive the RF signal, to filter and amplify the incoming signal in different frequency bands simultaneously and then to
down-convert and quantize the signals, in order to obtain digital intermediate-frequency forms, which can be used by the
- MGSE GTEC© Replay Unit: Digital GNSS IF or analog RF data
Both, synthetically generated and/or recorded real-world GNSS data can be replayed either as digital IF GNSS signals or
as analog RF multi-band data in real-time to receivers/components under test. The MGSE Replay Unit includes a flexible
multi-band, USB3.0 digital and analog RF replay device, that can stream the GIPSIE®-IFS generated and
GTEC©-RFFE recorded raw IF data to a digital baseband output or to an analog RF signal.
However, each element will also be functional as stand-alone unit.
- MGSE GIPSIE® Simulator software hosted on dedicated computer
- MGSE GTEC© Recording and Replay Unit both connected to a.m. computer
Possible MGSE configurations:
- MGSE full system consisting of Simulator, Recording and Replay Unit
- MGSE Recording Unit
- MGSE Replay Unit
- MGSE Simulator and Signal Generator
MGSE will be capable of providing both digital IF GNSS signals as well as analog RF multi-band data in real-time to
receivers/components under test. It will be possible either to synthetically generate data using the simulation modules,
which are able to simulate arbitrary scenarios with different settings or effects, or to record real-world data. The GNSS
data – both synthetically generated and recorded – can then be replayed (exactly reproducible).
The key design characteristics of MGSE are listed below:
|GNSS multi-system, multi-frequency scenarios:|
- GPS: L1 C/A & P; L2 L2C & P; L5
- Galileo: E1 A (PRS-like), B & C; E5, E5a/b; E6 A (PRS-like)
|Simulation of jamming & multipath signals||x||n/a||x|
|Notes:SIM = Simulation Channels & Signals|
RX = Receiving Channels & Signals
TX = Transmitting Channels & Signals
One common approach for saving costs during global navigation satellite system (GNSS) receiver or algorithm development,
qualiﬁcation, and certiﬁcation phases is to use a simulation environment with the capability to record/replay real-world
samples rather than performing resource- and time-intensive ﬁeld testing and validation. Moreover, as there are some GNSS
(e.g. Galileo, BeiDou, IRNSS) signals not fully available in space yet and due to repeatability of testing, manufacturers
use commercial hardware GNSS signal generators to simulate GNSS constellations, signals, and interfering sources.
Nevertheless, even the best synthetically generated simulation environment cannot reproduce reality better than recorded
live samples. Live samples from the sky are the ideal counterpart to the synthetic simulated samples.
Flexible and cost effective recording and replaying solutions of the nowadays mostly multi-frequency band GNSS signals are
required. Thus, record/replay provides the ability to conduct an accurate and comparative evaluation, since the same test
conditions can be used for any device. In turn, record/replay scenarios introduce some impairments as well. The recorded
signal can only be replayed exactly as received, only the amplitude can be controlled by the operator. A simulation scenario
does not have this limitation. The satellite signals can be individually manipulated and artificial errors can be introduced.
This is not possible using record/replay scenarios.
In the summary of the alternative solutions we focus on both GNSS record & replay devices and GNSS constellation &
signal simulation, since this is the main target in this project. In applying this criterion 4 competing alternative solutions
TeleOrbit GmbH (Project lead)
TeleConsult Austria GmbH
European Space Agency (ESA) – GSTP 6