Question: In UTRA UEs, what triggers a change in the transmitter's output power for uplink power control, differential accuracy, assuming the path loss weighting parameter equals 0?
Option 1: A change in the downlink transmission power by the Node B.
Option 2: Receipt of new Dedicated Physical Channel (DPCH) data from the UE's higher layers.
Option 3: Alteration in the UE's mobility state, transitioning between idle and connected modes.
Option 4: A step change in signalling values such as SIR Target, IBTS, or DPCH Constant Value received from higher layers.
Explanation: According to the uplink power control principles for differential accuracy in UTRA UEs, when the path loss weighting parameter is set to 0, the transmitter's output power adjustment is directly influenced by changes in specific signalling values. These include SIR Target, IBTS (Interference Budget per Traffic Source), or DPCH Constant Value, which are received from higher layers. This ensures dynamic adaptation to maintain optimal signal quality without being directly influenced by downlink path loss adjustments at this parameter setting.