Question: For a UTRA FDD UE supporting HSDPA, what is the frequency range relative to the UE centre carrier frequency to which the spectrum emission mask applies?
Option 1: Between 100 kHz and 500 kHz away from the UE centre carrier frequency
Option 2: Between 500 kHz and 2.5 MHz away from the UE centre carrier frequency
Option 3: Between 12.5 MHz and 25 MHz away from the UE centre carrier frequency
Option 4: Between 2.5 MHz and 12.5 MHz away from the UE centre carrier frequency
Explanation: This is correct because, according to the specifications for UTRA FDD UEs that support HSDPA (starting from Release 5), the spectrum emission mask's applicability is defined within a specific frequency range relative to the UE's center carrier frequency. The correct range, as per the telecom standards for managing out-of-channel emissions and ensuring spectral efficiency, is indeed between 2.5 MHz and 12.5 MHz away from the UE centre carrier frequency. This ensures that the UE's transmissions do not excessively interfere with neighboring channels while maintaining efficient use of the radio spectrum.