Presentation Outline. The NavSAS group; Examples of Software-Radio Technology in GNSS;

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1 Telemobility 2008 Progetto Galileo ed altri GNSS Development of GPS-Galileo Galileo Software Radio Receivers Marco Pini - NavSAS group

2 Presentation Outline The NavSAS group; Basic on Software-Radio Technology; Examples of Software-Radio Technology in GNSS; The Software Receiver developed in IRGAL: design, features, performance; Applications of the IRGAL receiver; Conclusion.

Technology in GNSS; The Software Receiver developed in

3 The NavSAS Research Group The Navigation Signal Analysis and Simulation (NavSAS) research group is a joint team of ISMB and Politecnico di Torino that acts in the satellite navigation and localization sectors in the Galileo Lab located at ISMB At present, the NavSAS is composed of 20 researchers Research activities are mainly focused on advanced technologies for GPS/EGNOS/Galileo receivers and applications The NavSAS cooperates with ih the main industrial i and institutional players operating in the in the field 6 researchers worked on the IRGAL Project

of 20 researchers Research activities are mainly focused on advanced technologies for GPS/EGNOS/Galileo receivers and applications The

4 The NavSAS Interest Advanced receiver technologies IRGAL GNSS receiver design and prototyping Design and realization of NAV/COM hybrid platforms Algorithms and innovative architecture against interference and multipath Global Navigation Satellite Systems Design of new GNSS signals Members of the GSTF Wide Area Augmentation Systems EGNOS monitoring station at ISMB supported by ESA Indoor applications Technologies for Emergency managements and dsol applications Higher Education Master on Navigation and Related applications Algorithms and implementation of Assisted GPS techniques Scientific applications such as receivers for LEO satellites

Augmentation Systems EGNOS monitoring station at ISMB supported by ESA Indoor applications Technologies for Emergency managements and dsol applications Higher

5 Software Radio Technology: Basic Concept Simple fundamental design philosophy: h Place the ADC as close as possible to the antenna in the chain of front end components. Process the resulting samples via software using a programmable microprocessor. Major Advantages 1. Removal of analog components and their nonlinear, temperature-based, agebased characteristics. Software-based receiver; 2. A single antenna/front end configuration can be used to receive and demodulate a variety of distinct signals. Flexible and multi-standard receiver. 3. The software radio provides the ultimate simulation/testing environments. Reconfigurable receiver.

Removal of analog components and their nonlinear, temperature-based, agebased characteristics. Software-based receiver; 2.

6 Software Radio Technology: Advantages Software Radio represents an enabling technology for the realization of receivers On the contrary, terminals operated on dedicated HW platforms for specific applications (ASIC) do not have reconfiguration capabilities In a Software Radio receiver replaces dedicated HW wherever possible Cost reduction, Increased versatility, Reduced time for design, debug and test A Software Radio terminal supports: Coexistence of several SW modules implementing different communication standards (multiservice, multi-mode terminals, etc ) Dynamic reconfiguration ability Major research groups working on software-radio technology in GNSS: GNSS Group, University of Colorado (USA); Positioning, Location and Navigation Group, University of Calgary (Canada); Danish GPS Center, University of Aalborg (Denmark) R&D Departments t of major ICT companies (Nokia, CSR, Samsung )

and test A Software Radio terminal supports: Coexistence of several SW modules implementing different communication standards (multiservice, multi-mode terminals, etc ) Dynamic reconfiguration

7 The NordNav Software Receiver The NordNav Receiver was the first real-time fully software GPS receiver. Came out in 2000 Nordnav Technologies started as a spin-off of the Lulea University (Sweden) The NordNav receiver was extensively used in GNSS research labs, worldwide Although the NordNav Receiver was extremely useful, NavSAS researchers and other groups realized the need to develop their own real-time receivers IRGAL Project In January 2007, NordNav Technologies has been acquired by Cambridge Silicom Radio (CSR) for 75 $ million.

in GNSS research labs, worldwide Although the NordNav Receiver was extremely useful, NavSAS researchers and other groups realized the

8 IRGAL Software Receiver: Features In the IRGAL project we designed and realized a software GPS/Galileo receiver, with enhanced characteristics with respect to some of the existing software-based GNSS receiver Real time software receiver; Hard and limiting constraints for Wider IF bandwidth; 8 bits digitization; USB 2.0 interface toward the Front-end; the software-based receivers New, respect to existing GNSS software-based receivers Low level reconfigurability (Number of channels, type of signals GPS, Galileo, EGNOS, Signal Acquisition iti parameters, Tracking structures, t PVT computation ti rate); Nav-Com software receiver. Assisted-GPS software routines, that recover A-GPS data employing the OMA-SUPL protocol; Output files using the NMEA and RINEX 3.0 standard formats

0 interface toward the Front-end; the software-based receivers New, respect to existing GNSS software-based receivers Low level reconfigurability (Number of channels, type of signals GPS,

9 IRGAL Software Receiver: Architecture Software receiver routines GUI Logger Communication Module TCP/IP Communication Module Standard USB 2.0 interface Any front end (i.e.: different sampling frequency and number of samples) with such an interface can be easily plug into the PC and used Nice feature with respect to other known software receivers, that need their own front end. Positioning Nav Msg Pseudorange Decoding Evaluation Tracking Hi-Rate Logger Hardware Front end: Amplifiers, Filters, Mixer, ADC USB 2.0 Acquisition USB 2.0 Driver Signal Analysis

face Any front end (i.e.: different sampling frequency and number of samples) with such an interface can be easily plug into the PC and

10 Lab Front end Prototype I Survey-grade pinwheel Antenna (Novatel 702L) Dual frequency GPS L1 L2 Built in LNA - Front end slaved to external signal/function generators (frequency plan easily reconfigurable) - Raw data sent to the PC through a USB interface - High analog IF, MHz - Use of the downsampling strategy, further frequency downconversion to MHz, sampling rate: MHz To the NavSAS Lab RF section From the antenna Ampl. Wideband 40 db gain Power Splitter L1 Filter B=23.63 MHz IF Filter B=8.0 MHz Ampl. 19 db gain Ampl. 19 db gain IF Filter B=6 MHz Dual channels ADC LO 1 = MHz IF section Quantization over 8 bits Unique feature of the IRGAL software receiver w.r.t. other known software receivers, that use less bits (1,2,4 bits) The higher number of bits allows for implementing and test innovative algorithm, such as interference detection techniques. Added values for future SOL applications

5103 MHz To the NavSAS Lab RF section From the antenna Ampl. Wideband 40 db gain Power Splitter L1 Filter B=23.63 MHz IF Filter B=8.0 MHz Ampl. 19 db gain Ampl.

11 Lab Front end Prototype II RF-IF sections Dual channel ADC 8 bits USB interface

12 Lab Front end Prototype: Applications This front end has been used in all the tests of the receiver, as well as in the tests of some components of the IRGAL multifrequency front end Test of the LO Test of the ADC

well as in the tests of some components of the IRGAL

13 Commercial Front end The software receiver can work with any front end having a USB interface. The IRGAL receiver works well with the SiGe GN3S Sampler v2 ( GPS L1 / Galileo E1 front end: - Small, versatile GNSS front end; - Connected to the PC with a USB 2.0 interface; - Based on the SiGe 4120 GPS ASIC; - Provide the I and Q samples of the signal at baseband; - Can be set to digitalize the signal using 1 or 2 bits; 2- Lab prototype multifrequency GNSS front end 1- GN3S Sampler v2

products_id=8238) GPS L1 / Galileo E1 front end: - Small, versatile GNSS front end; - Connected to the PC with a USB 2.

14 IRGAL Software Receiver: GUI Screenshot I Processing results on each digital channel Position displayed on a digital map Geometric parameters

15 IRGAL Software Receiver: GUI Screenshot II Processing results on each digital channel Early, Late and Prompt correlators Tracked satellites displayed on a polar diagram Estimated C/No

16 Galileo-Ready Receiver: Test on GIOVE-A Signals Navigation data message broadcasted by GIOVE-A, recovered by the software receiver Torino Tracking declared lost at am GIOVE-A acquired and started being tracked at am Local and incoming codes synchronized over time GIOVE-A tracked over the whole pass above Torino, on the 4th of March 2008, for 6h and 15 min

40 am GIOVE-A acquired and started being tracked at 03.17.

17 IRGAL Software Receiver: Performance Parameter Description Rx Performance Receiver Characteristics - More than 12 channels in real time - L1/E1 only, C/A code + Binary Offset Carrier (BOC)(1,1) (upgradable to Multiplexed Binary Offset Code (MBOC) easily) - Position Accuracy: r.m.s< 10 m using code-based measurements and without applying carrier smoothing techniques. - Time to First Fix in Cold Startt mode lower than 45 seconds Software Performance - Current Operative Platform: Gentoo Linux with Kernel 2.6 POSIX (completely Open Source) - Sampling Frequency of MHz; Sample resolution 8 bits - Running on a Intel Pentium 4 standard architecture (SSE,SSE2,SSE3,SSSE3) - Maximum CPU load with 12 real time channels in navigation mode and receiver performing PVT with a rate of 2 Hz of 50% on a 3GHz processor.

- Time to First Fix in Cold Startt mode lower than 45 seconds Software Performance - Current Operative Platform: Gentoo Linux with Kernel 2.6 POSIX (completely Open Source) - Sampling Frequency of 17.

18 Software Receiver Roadmap I today Research projects Support to research on GNSS technology Receiver ready for all the people IRGAL receiver is an useful tool for future in the lab to support research projects and will boost research on GNSS technology today 30/09/08 Software maintanance will be needed periodically Innovative Applications Support to SMEs and other interested groups End of the IRGAL project. Development of an integrated t USB front end (easily portable) Interested SMEs and other research groups might collaborate with the NavSAS people, borrow and use the receiver and help to improve performance and customize the receiver for their applications. Software maintanance and upgrade might be required

other interested groups End of the IRGAL project.

19 Software Receiver Roadmap II NAV/COM Integration Following the trend of mass-market receivers, the IRGAL software receiver is already implementing Assisted-GPS software routines, that recover A-GPS data employing the OMA-SUPL protocol from communication networks (GSM/UMTS) today 30/09/08 Nav-Com platform Embeded GPS/Galileo receiver on dedicated hardware End of the IRGAL project. Development of an integrated USB front end (easily portable) Deep analysis on the optimization of the GNSS algorithm Accurate evaluation of the targett platform Smart coding

(GSM/UMTS) today 30/09/08 Nav-Com platform Embeded GPS/Galileo receiver on dedicated hardware End of the IRGAL project.

20 Conclusion One important output of the IRGAL project is the GPS-Galileo real-time software receiver; Outstanding tool for research on GNSS receivers; The Software Receiver is already in use at the Galileo Labs at ISMB and testes by NavSAS researchers Still space for performance improvements, add new features and tests.

The Software Receiver is already in use at the Galileo Labs at ISMB and testes

21 Contact Info Thank you for your attention Marco Pini Office:

The NavSAS Research Group

Navigation, Signal Analysis and Simulation Group The NavSAS Research Group NavSAS research group is a joint team of Politecnico di Torino and ISMB Research in the areas of satellite navigation and Positioning