Question: In an E-UTRAN TDD to UTRAN FDD handover scenario, what is the maximum allowed time for a UE to start transmitting the UL DPCCH to the target cell after receiving the RRC message implying handover?
Option 1: Less than 100 ms from the beginning of a specified time period
Option 2: Less than 140 ms from the end of another time period
Option 3: Exactly 190 ms from the start of a particular time period
Option 4: Less than 190 ms from the beginning of the relevant time period for handover response
Explanation: This reflects the specified requirement for the UE's response time after receiving the handover command, ensuring seamless handovers and maintaining service continuity. The correct timing is critical, highlighting the importance of precision in telecom protocols.