Question: In immunity tests for Active Antenna System (AAS) Base Stations (BS), which performance metric is monitored in the uplink for UTRA TDD and UTRA FDD, but not for E-UTRA or NR?
Option 1: Signal-to-Noise Ratio (SNR)
Option 2: Block Error Rate (BLER)
Option 3: Throughput
Option 4: Handover Success Rate
Explanation: According to the assessment of performance in uplink for AAS BS, BLER is specifically monitored for UTRA TDD and UTRA FDD, whereas throughput is the metric for E-UTRA and NR. This distinction highlights different performance criteria based on the radio access technology (RAT) used, emphasizing tailored testing approaches for ensuring telecommunications systems' reliability across various standards.