摘要 |
<p>A method for detecting fraud in a cellular radio telephone system. Fraud is suspected when the system detects a multiple access from a mobile station (Figs. 2 and 3A-B), when an activity collision occurs (Figs. 4-6), when the system receives a premature registration from the mobile station (Figs. 9A-B and 10), when auditing or operator-initiated locating of the mobile station reveals the existence of the mobile station in two locations simultaneously (Figs. 12-13), or when tracing of mobile subscriber activity reveals unusual activity (Figs. 14-17).</p> |