Question: In a UMTS network, during an inter-cell soft handover involving cells defined by the Radio Link Set (RLS), what is the primary purpose of transmitting E-HICH (Enhanced-Harq Indicator Channel) using 12 consecutive slots from Cell 1 (containing the Serving E-DCH cell)?
Option 1: To increase the transmission power of the Serving E-DCH cell.
Option 2: To reduce the number of retransmissions in Cell 2 (not containing the Serving E-DCH cell).
Option 3: To enhance the reception quality of voice calls in both cells.
Option 4: To verify and maintain an average probability for missed ACK (Acknowledgement) below specified thresholds.
Explanation: The correct answer, Option 4, aligns with the test purpose mentioned, which is to ensure that during an inter-cell soft handover, the average probability of missing an ACK signal, when E-HICH is transmitted over 12 slots from Cell 1, does not exceed predetermined values. This is crucial for maintaining reliable data transmission and efficient use of network resources in UMTS networks, particularly in scenarios involving handovers between cells with different serving E-DCH configurations.