A little more on the inner workings of this system:
The HWS tracking system consists of three components a GPS collar, gateway router and relay stations. The Gateway router allows data to be downloaded wirelessly, from the GPS collar, via the mesh network and then transmits the data to the internet through existing GSM networks. The relay stations allow the wireless network to be extended to cover a larger area or overcome signal obstructions. By making use of a gateway and relay stations our tracking collars are capable of functioning in areas where GSM reception is poor and normal GSM/GPS collars cannot be used.
More information on these components can be found here.