Navigation Engineering & 3D Spatial Sciences

Technical Overview

GRIFFIN – Technical Overview

The GRIFFIN system comprises of multiple sets of RF signal reception nodes, referred to as Sensor Nodes (SNs), typically deployed surrounding secure facilities e.g. airbases, airports, ports and/or other critical infrastructure that needs to be protected, in addition to, one or more Central Nodes (CNs) that coordinate and control the GRIFFIN system. 

The GRIFFIN system consists of several Sensor/ Monitoring Nodes installed surrounding a regional area encompassing mission critical GNSS applications that require protection. Typically, several networked Sensor Nodes are installed around the perimeter, while controlled from a single central command location. This Central Processing Unit, coordinates each Sensor Node’s RF 360deg azimuth searching using both the electronically steerable antenna arrays and advanced signal processing techniques. When any RF interference or Spoofing instances are detected, the Central Processing Unit quickly tasks each remote Node to optimise beam forming for the required direction to intercept the target RFI signal(s), then collects and processes spectral data for geo-location function.

Using the combination of AOA data generated by each Node and combined TDOA processing of Node spectral data at the Central Processor location, any RFI source in the GPS frequency bands is quickly detected and geo-located to accuracies of a few metres within seconds. The location and type of interference is quickly and automatically passed to the appropriate authorities to deliver the required remedial action.

Multi element electronic antenna arrays for facilitating infinite combinations of rapidly switchable high gain (20+dBi) beams and/or deep nulls for complex directional patterns. The synthetic directional beams facilitate both intense focusing on the RFI targets and GNSS satellites during intentional signal acquisition. Then under different circumstances, deep nulls are used to reject GNSS satellites (considered unwanted background noise) while focusing on weak RFI targets at long distances.