Software Defined Radio
Software Defined Radio

INTECS develops receivers for Satellite Navigation based on “Software Defined Radio” (SDR) techniques. The SDR approach consists in processing radio signals in a combination of software and firmware, rather than relying primarily on fixed-function.

This improves flexibility, evolution capability (in functions and Air Interfaces), maintenance, support of new intelligent services (e.g.: by integrating many information sources), testing and RAMS requirements for safety critical system applications, easy creation of simulated scenarios, and the possibility to support BITE operations.

SOFT-REC Product
The SOFT-REC Product is a real time GPS-EGNOS L1 software receiver completely written in the "C" language and running on a standard PC with the Real Time Linux operating system.  It represents a successful experience with CDMA signal processing.

The latest development included GALILEO receiver capability, GALILEO and GPS software receivers are now realized in the same unit and can be operated in combination.

The extension to support the E1, E5 and E6 bands is being finalised, and the SISNeT network connection could easily be integrated to improve receiver accuracy and verify system integrity. SOFT-REC includes the following main functions:

- Signal acquisition
- Signal tracking
- Navigation solution (estimate of the user position)
- Kalman filter: (PVT measurements)
- MMI (A standard graphical user interface controls receiver operation). 

The TTFF (Time To First Fix) at cold start-up (lack of almanac and ephemeris data) is less than 60 seconds.  

GALILEO GROUND SEGMENT
The SOFT-REC product is currently used in the “Galileo Test Range” (GALILEO signal permanent laboratory) and in the “GALILEO Ground System Integration & Validation”.  

ON-BOARD SATELLITE MISSIONS
INTECS is developing two versions of a GPS / GALILEO software receiver for two different Micro-Satellite Missions:

1- “Micro-Satellite Formations” technological study project;
2- Satellite Navigation Payload for MIOSAT EO Satellite.