Question: In a UTRA FDD network, what triggers the Open Loop Power Control in the uplink for DC-HSUPA in a UE, specifically for initial Dual Cell transmission in CELL_DCH state?
Option 1: Uplink data rate adjustments based on UE buffer size
Option 2: Downlink received signal power level of the CPICH and Node B's RADIO BEARER SETUP message
Option 3: Periodic uplink power headroom reports from the UE to the eNodeB
Option 4: Handover command from the serving cell to a neighboring cell
Explanation: Open Loop Power Control for DC-HSUPA in initial Dual Cell transmission relies on the downlink received signal power level of the Common Pilot Channel (CPICH) as a reference, combined with specific settings provided by the Node B through the RADIO BEARER SETUP message. This ensures the UE sets an appropriate output power for each carrier, optimizing uplink transmission in CELL_DCH state without immediate feedback loop adjustments.