Question: What is the primary purpose of implementing Timing Advance in a TDD (Time Division Duplexing) UTRA Network?
Option 1: To synchronize UE transmissions with Node B's scheduling for efficient resource allocation.
Option 2: To compensate for variations in signal strength due to fading in the radio environment.
Option 3: To adjust UE transmit timing and mitigate the effects of large delay spread at the Node B.
Option 4: To enhance security by introducing a time-varying offset in UE transmissions.
Explanation: The correct answer, Option 3, highlights the fundamental reason for implementing Timing Advance in TDD UTRA Networks. By adjusting the User Equipment's (UE) transmit timing, Timing Advance effectively counters the detrimental impact of large delay spreads at the Node B (the base station), ensuring more reliable and efficient communication. This is crucial in TDD systems where uplink and downlink share the same frequency band but are separated in time, making precise timing essential to prevent interference and data loss.