Question: In UTRAN Iub interface (NBAP signalling), what is the primary purpose of the Secondary UL Frequency Update procedure for a UE in Dual Cell E-DCH operation?
Option 1: To notify the RNC about changes in the UE's downlink packet scheduling.
Option 2: To inform the CRNC about updates or changes to the activation state of the secondary UL frequency, especially with E-DCH decoupling.
Option 3: To request a handover from one Node B to another due to poor uplink signal quality.
Option 4: To initiate a bearer modification for QoS enhancement in the uplink direction.
Explanation: The correct answer, Option 2, accurately reflects the purpose of the Secondary UL Frequency Update procedure as related to informing the CRNC (Controlling RNC) about updates or changes in the activation state of a UE's secondary uplink frequency during Dual Cell E-DCH operations, particularly when Enhanced Dedicated Channel (E-DCH) decoupling is configured. This procedure ensures the network is aware of and can manage the UE's uplink resource utilization effectively, which is crucial for maintaining optimal network performance and user experience in scenarios involving dual cell enhancements.