POSITION DETERMINATION SYSTEM FOR WIRELESS COMMUNICATION DEVICE

摘要

A wireless position determination system (640) includes a power adapter configured to couple to a pre-existing power supply (650), such as an automotive cigarette lighter. The power adapter has a two-level voltage translator (648) for translating a voltage provided by the power supply (650) into two voltage levels. A wireless communication device (642) is coupled to the power adapter and receives one voltage level from the power adapter. A position-determination device (642) determines the location of the wireless device (642) using a GPS antenna (644) and receiver (646), and generates location data. It is coupled by a power/data line (608) to the power adapter and receives the other voltage level from the power adapter, and transmits the location data to the power adapter. The power adapter, in turn provides the location data to the communication device. The location data is sent to a remote server using a novel DTMF messaging syntax including a message separation sequence, a field separation character, and at least one predefined message field.