Question: In 4C-HSDPA HS-DPCCH, under static propagation conditions and with a receiver input signal at a specified Ec/N0 limit, what is the maximum allowed error ratio for ACK (Acknowledgement) false alarms?
Option 1: 10^-1
Option 2: 5 × 10^-2
Option 3: 5 × 10^-3
Option 4: 10^-2 or less
Explanation: The correct answer is aligned with the performance requirement for ACK false alarm in static propagation conditions for 4C-HSDPA HS-DPCCH, emphasizing the importance of reliable acknowledgement transmission. An error ratio of 10^-2 or less ensures that the system maintains a high degree of accuracy in acknowledging received data packets, which is crucial for efficient retransmission handling and overall network performance. This threshold strikes a balance between the inevitability of some errors in wireless communications and the need to maintain service quality.