Galileo REceiver for the mAss
Background & Objectives
High volume mass-market receivers are key to opening up the market for precision location services and to helping a number of suppliers move quickly towards volume supply. Through this project the GREAT consortium will exploit the special characteristics of the Galileo signal to deliver real benefits to the European consumer and the location-based services market. The EU forecasts a rapid adoption of dual-system GNSS receivers which support both GPS and Galileo. By 2011, more than 50% of the installed base of GNSS receivers will support Galileo. This in turn means that the majority of new GNSS receivers sold are dual system GNSS receivers.
The predicted fast adoption depends significantly on the success of deploying the Galileo systems and the promised technical benefits turning into reality. The low cost, low power consumption, low footprint, good accuracy and high sensitivity are key benefits to the user and are the main attributes of a typical mass-market receiver, especially for the receiver to be used in a mobile terminal. Improved TTFF (small search space) is crucial to the user, for instance, when positioning an emergency call.
GREAT will deliver a library of IP elements exploiting the special capabilities of the Galileo signal. The project is researching and developing technologies for mass-market receivers, which include the development of novel front-end RF designs and baseband technology, as well as the advanced algorithms for multipath mitigation, hybrid data fusion and assisted GNSS.
GREAT consists of six work packages, one for each of the objectives, addressing the various technology areas for a mass-market receiver. The project will comprise three distinct phases – core technology development, prototyping and testing – achieving major blocks of demonstrable baseband IP, which in turn will allow further developments to be kick-started.
The project has the following objectives:
- Study, design and develop a RF sub-system, able to operate with Galileo and GPS satellite signals in the presence of the 2G/3G cellular signals and to investigate the multiband approach covering different frequency bands.
- Study, design and develop a ‘fast track’ Galileo advanced baseband, capable of operating with both the Galileo and GPS signals in the L1-E5a dual band.
- Investigate advanced multipath mitigation (MM) algorithms. GREAT will develop a software test environment for MM algorithms and assess the potential performance improvement and impact on receiver hardware.
- Identify critical scenarios where pure GNSS navigation is not sufficient and investigate the use of efficient hybrid data fusion (HDF) algorithms for PVT computation using multiple sources. GREAT will develop a test and simulation environment for HDF algorithms. GREAT will also assess the impact of HDF on the hardware design of mass-market navigation receivers.
- Investigate the enhancements needed or made possible by Galileo, leading to high accuracy, fast TTFF designs. Assisted-GNSS uses assistance data available from the mobile phone network to enables accurate location with improved sensitivity and time-to-fix. GREAT will investigate A-GNSS architectures and also provide liaison into 3G standards bodies.
- Promote dissemination and exploitation of results from all Work Packages to influence the future broadband mobile radio cellular (4G) systems.
Work performed & results
The low cost, low power consumption, low footprint, good accuracy and high sensitivity are the key benefits to the user and are the main attributes of a typical mass-market receiver front-end, especially for the receiver to be used in mobile terminal. The GREAT RF front-end chipset will also provide a flexible and easy to use interface, allowing rapid conversion in a single chip receiver and consequent implementation into existing basebands. Likewise the advanced baseband technology for GNSS receivers, developed by GREAT, keeps the system costs low, which is one of the crucial requirements for a mass-market receiver. This technology of a ‘fast track’ Galileo baseband consumes less power, supporting different Galileo system services and the complete receiver will be able to compute positions from mixed constellations (e.g. 3D position from two GPS and two Galileo satellites). GREAT will also provide more sophisticated algorithms improving the end-user experience. Multipath mitigation (MM) algorithms can reduce the multipaths in complex urban scenarios where there will probably be a greater number, and this MM can also lead to greater accuracy and better positioning in complex scenarios. Where pure GNSS navigation is not sufficient Hybrid Data Fusion (HDF) algorithms allow for PVT computation from multiple sources – cellular and GNSS. Finally, assisted-GNSS enables accurate location with improved sensitivity and time-to-fix.