PRS Search Prioritization via GDOP Geometry

The patent applies preliminary action by computing GDOP values for all candidate wireless transmitters before the actual PRS search process. The mobile device obtains rough location information, calculates GDOP for each transmitter based on this location and transmitter positions, and creates a prioritized list of transmitters sorted by GDOP values. This preliminary GDOP-based sorting enables the subsequent PRS search to efficiently focus on transmitters with good measurement geometry, thereby improving positioning accuracy without significantly increasing overall system complexity.

The patent applies local quality by treating different wireless transmitters differently based on their individual GDOP values. Instead of uniformly searching all transmitters, the mobile device calculates GDOP for each transmitter and assigns different priorities accordingly. Transmitters with low GDOP values (good measurement geometry) are prioritized for PRS search, while transmitters with high GDOP values (poor geometry) are deprioritized or excluded. This differentiated approach reduces power consumption by avoiding unnecessary searches of poor-quality transmitters while maintaining positioning reliability through selective focus on high-quality transmitters.

The patent applies segmentation by dividing the set of all candidate wireless transmitters into prioritized groups based on GDOP values. The mobile device creates a sorted list where transmitters are segmented into high-priority (low GDOP), medium-priority, and low-priority (high GDOP) groups. The PRS search process then sequentially attempts to acquire signals from transmitters in order of priority, stopping when sufficient measurements are obtained or time expires. This segmentation enables the system to achieve good positioning accuracy within the limited response time by focusing computational resources on the most promising transmitters first.

The patent applies dynamics by making the PRS search process adaptive based on real-time GDOP calculations. The mobile device dynamically determines the priority order of transmitters to search by computing GDOP values for each transmitter relative to the device's rough location. This dynamic prioritization allows the system to flexibly adapt to different geographic configurations and device locations, automatically identifying and focusing on transmitters with good measurement geometry while excluding or deprioritizing those with poor geometry, thereby maintaining high positioning accuracy regardless of the total number of available transmitters.