Question: In a TDD (Time Division Duplex) system with a 1.28Mcps option, what is the maximum allowed time for a User Equipment (UE) to complete cell re-selection, from the start of the T2 period to sending a URA UPDATE message in the new cell?
Option 1: Less than 5 seconds
Option 2: Less than 6.4 seconds
Option 3: Less than 8 seconds
Option 4: Less than 10 seconds
Explanation: The correct answer is based on the requirement for cell re-selection delay in a TDD system, which stipulates that the time from the beginning of the T2 period to when the UE camps on a new cell (Cell 2) and initiates the URA UPDATE message transmission should be less than 8 seconds. This ensures efficient handover without excessive delay, impacting user experience and network performance.