US Patent 7664049 Multilayer telecommunications network

A communications system comprising: a first network comprising a plurality of first network subscriber units and a first network sink node unit capable of wireless communication with the first network subscriber units; and a second network geographically at least partly overlapping the first network and comprising a plurality of second network subscriber units and a second network sink node unit capable of wireless communication with the second network subscriber units; and a dedicated connection between the first network sink node unit and a second network unit capable of communication in the second network, whereby a first network subscriber unit may be provided with a communication path to another second network unit.