srx-10i System Architecture
The srx-10i system includes two components:
- Network of local monitors, each individual one including an RF Front-end and real-time processing software running in a dedicated computer (see figure below)
- Central monitoring and analysis system, which collects the data sent and alarms raised by the local monitors, and provides analysis capabilities to process the recorded signal samples and characterize the interference events
The system can be easily integrated in already existing GNSS monitoring networks (e.g.; GPS or EGNOS monitoring systems).
Each local monitor processes the RF signal, potentially contaminated by interference, by digitally converting the I+Q samples obtained from the front-end and forwarding them to the host computer via an USB port.
The samples are then processed in order to compute the Power Spectrum Density (PSD), which, after calibration of the noise floor, is used for identification and characterization of interferences present in the input signal.
When interferences are detected, a flag is raised and, after a few seconds, a set of raw samples from a circular buffer is hard-disk recorded including past and future samples with respect to the time when interference was detected. These files of samples can be locally re-analyzed or post-processed with the analysis tools.