MGSE

Multi-GNSS Simulation & Test Environment

Brief Description

MGSE creates a GNSS simulation environment that consists of:

1. 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.
2. 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 actual receiver.
3. 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.

The MGSE integrated system will be composed of

• MGSE GIPSIE® Simulator software hosted on dedicated computer
• MGSE GTEC© Recording and Replay Unit both connected to a.m. computer

However, each element will also be functional as stand-alone unit.

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:

Performance parameter SIM RX TX GNSS multi-system, multi-frequency scenarios:

• GPS: L1 C/A & P; L2 L2C & P; L5
  xxx
• SBAS: EGNOS/WAAS/MSAS L1
  xxx
• Galileo: E1 A (PRS-like), B & C; E5, E5a/b; E6 A (PRS-like)
  xxx
• GLONASS: G1, G2
  xxx
• BeiDou: B1, B2
  xxx
• QZSS: L1, L1C, L2C, LEX
  xxx
• IRNSS: L5 and S-Band
  xxx

Simulation of jamming & multipath signals

xn/ax

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 are left.