A system and method that uses an advanced positioning system in combination with a cellular communication network to improve the performance of the network is disclosed. The system is capable of receiving an identification number for a mobile unit as well as a location code. In order to determine if the mobile unit is a fraudulent user of the cellular communication network, the system compares the location code with a previously received location code. Since there are natural physical constraints on how quickly a mobile unit can move from one location to another, the system can thereby determine if there are two mobile units using the same identification number. If so, then one is likely a fraudulent user. In addition, the system is capable of assisting the mobile unit by providing the location code to a third party. This is especially beneficial for emergency dispatcher services since, due to the very nature of mobile units, the user of the mobile unit may not know his precise location.