MUSIM RRC Timer Handling for Stable USIM Switching

The patent segments the long-time switching timer management into separate independent timers for each USIM card. When the UE supports multiple USIMs, it maintains separate RRC connections with each network, and each connection has its own long-time switching timer running independently. This segmentation approach allows the UE to manage multiple USIMs simultaneously without the timers interfering with each other, thus improving communication versatility while keeping the management complexity manageable through clear separation of timer instances.

The patent implements preliminary action by restarting the long-time switching timer at each USIM switch operation. When the UE switches from one USIM to another, it proactively restarts the timer for the newly activated USIM, ensuring that the connection remains active and stable. This preliminary action prevents timer expiration during frequent switching operations, maintaining communication stability while allowing flexible USIM switching. The timer is restarted before potential connection issues can arise.

The patent applies segmentation by creating separate long-time switching timer instances for each USIM card rather than using a single shared timer. Each USIM has its own dedicated timer that runs independently, eliminating timer conflicts and interruptions that would occur with a shared timer. Although this increases device complexity slightly by requiring multiple timer instances, it significantly improves communication reliability by ensuring that timer operations for one USIM do not interfere with or disrupt connections for other USIMs.