| 摘要 |
A stolen asset locating and recovery system comprises: a first locating device (LD) associated with a first asset. The first LD has a first wireless communication unit comprising a public mobile radio network (PMRN) enabled communication unit for communicating over a PMRN such as a GSM/GPRS network with any of: an operations control centre; a second LD associated with a second asset; or a mobile location tracking system. The first LD has a second wireless communication unit. The second wireless communication unit uses a different wireless technology or protocol to that of the PMRN enabled communication unit. In the case where the second communication unit is a private radio frequency network (PRFN) operated by the asset location system service provider, the first LD is configured to use said second communication unit to communicate directly over said PRFN with the second LD in order to convey information such as a preprogrammed sequence of signals which assists locating and recovering said asset. In the event that the second communication unit is enabled for communication on a public radio network (PRN), the first LD is configured to communicate with any of the operations control centre, the second LD, or the mobile location tracking system on a PRN such as an IEEE802.11 enabled wireless local area network (WLAN) or an IEEE802.16 enabled wireless metropolitan area network when it is determined at the first LD that the communication cannot be transmitted between said first LD and any of the operations control centre, the second LD, or the mobile location tracking system using the PMRN. |
