Dynamic Periodic Location Area Update in Mobile Networks

In mobile communications networks, periodic location area update (PLAU) is utilized to detect presence of a mobile station (MS). In 3GPP Technical Specifications 23.012 and 24.008, a fixed PLAU scheme was proposed for Universal Mobile Telecommunications System (UMTS), where the interval between two PLAUs is of fixed length. We observe that MS presence can also be detected through call activities and normal location area update (NLAU). Therefore we propose a dynamic PLAU scheme where the PLAU interval is dynamically adjusted based on the call traffic and NLAU rate. Analytic model is developed to investigate the performance of dynamic and fixed PLAU schemes. Our study provides guidelines to select parameters for dynamic PLAU.