Question: In a Missed ACK test for a UE (User Equipment) in an FDD (Frequency Division Duplex) system, if the UE indicates retransmission on the E-DPCCH (Enhanced Dedicated Physical Control Channel), what does this imply about the previous ACK (Acknowledgement) from the SS (Server/Network Side)?
Option 1: The UE successfully received the ACK and is sending new data.
Option 2: The UE received the ACK but is retransmitting due to packet error.
Option 3: The UE interpreted the previous ACK as a NACK (Negative Acknowledgement) or DTX (Discontinuous Transmission).
Option 4: The UE is experiencing congestion and slowing down transmission.
Explanation: According to the measurement principle for the Missed ACK test, if the UE transmits a retransmission on the E-DPCCH, it signifies that the UE interpreted the previous response from the SS (which was actually an ACK) as either a NACK or DTX. This misinterpretation leads to unnecessary retransmissions, counted as "missed ACK" in the test. This scenario highlights the importance of accurate acknowledgement reception in maintaining efficient data transfer over wireless networks.