Question: What are the possible Spreading Factors for an Orthogonal Variable Spreading Factor (OVSF) code used as a Channelisation Code in TDD (Time Division Duplex) mode in UTRAN?
Option 1: 3, 5, 7, 9, or 11
Option 2: 1, 2, 4, 8, or 16
Option 3: 2, 4, 6, 8, or 10
Option 4: 1, 3, 5, 7, or 15
Explanation: In TDD mode within UTRAN (Universal Terrestrial Radio Access Network), Channelisation Codes are implemented using Orthogonal Variable Spreading Factor (OVSF) codes. These OVSF codes can have specific spreading factors that allow for the efficient use of the available bandwidth while minimizing interference. The correct spreading factors for these codes, as per the defined standards for TDD operation in UTRAN, are indeed 1, 2, 4, 8, or 16, which directly corresponds to the options provided, highlighting the flexibility and scalability of the OVSF code application in TDD environments.