Priority measurement rules for channel measurement occasions

Abstract

Based on the determined signal strength of a serving cell, a choice is made whether to utilize a cell-FACH measurement occasion for a lower priority neighbor cell search or for a higher priority neighbor cell search. The lower priority neighbor cell search is for maintaining wireless connectivity and the higher priority neighbor cell search is for accessing enhanced wireless service. In specific examples the search may be inter-frequency for frequency layers with higher or lower priority than a serving layer of the serving cell, or the search may be inter-RAT such as the lower priority GERAN search and a higher priority E-UTRAN search if the serving cell is WCDMA. In one example there are two thresholds for the signal strength, and if higher than both then the measurement occasion is used for an E-UTRAN search regardless of whether GERAN or inter-frequency neighbour cells have been configured for the UE practicing the invention.

1 . An apparatus, comprising:
 at least one processor; and   at least one non-transitory memory storing a computer program;   in which the at least one non-transitory memory with the computer program is configured with the at least one processor to cause the apparatus to at least:   determine signal strength of a serving cell; and   choose, based on the determined signal strength, whether to utilize a cell forward access channel measurement occasion for a lower priority neighbor cell search or for a higher priority neighbor cell search,   in which the lower priority neighbor cell search is for maintaining wireless connectivity and the higher priority neighbor cell search is for accessing enhanced wireless service as compared to the serving cell.   wherein:   the serving cell operates according to a first radio access technology (RAT) which is WCDMA;   the higher priority neighbor cell search comprises a search in a third RAT which is E-UTRAN or in a frequency layer higher in priority than a serving layer of the serving cell;   the lower priority neighbor cell search comprises a search in a second RAT which is GERAN or in a frequency layer having a priority that is lower than or equal to priority of the serving layer of the serving cell; and   the measurement occasion is utilized for the lower priority neighbor cell search when the determined signal strength is below a threshold.