In some embodiments, the controller 210 may be configured to have access to and use a cellular network (e.g., cellular network 220 in FIG. 2). The controller 210 may (1) initially make contact with a base station (e.g., base station 110 in FIG. 1), and can then (2) register with the network. In some embodiments, during the first stage, the controller 210 may use a paging or control channel to send an attach message to a base station (or target cell site) on the cellular network, thereby indicating the presence of the UE 200. In some embodiments, once the attach message has been successfully sent, the controller 210 may perform a registration with the cellular network by (1) communicating with the network the identity of a subscriber to ensure that the subscriber account is valid, and (2) registering the UE with Home Location Register (HLR) and/or Visitors Location Register (VLR) of the cellular network so that the cellular network can keep track of the location/position of the UE. In some embodiments, after the registration, the controller 210 may update the register (HLR and/or VLR) with its position by periodically communicating with the network its position and status.
The above-described functions of the controller 210 may be embodied as hardware, or a combination of hardware and software/firmware. In some embodiments, the controller 210 may be integrated with the processor 204 or implemented as software executed by the processor 204.
