Question: What initializes the pseudo-random sequence generator for reference-signal sequence generation in a User Equipment (UE) device?
Option 1: The UE's unique identifier and the current frame number.
Option 2: The downlink PRS (Positioning Reference Signal) sequence ID alone.
Option 3: A combination of the slot number, the downlink PRS sequence ID, and the OFDM symbol within that slot.
Option 4: Only the OFDM symbol number within the slot to which the sequence is mapped.
Explanation: This option correctly identifies all elements required for initializing the pseudo-random sequence generator: the slot number, the downlink PRS sequence ID, and the OFDM symbol within the slot. This combination ensures the reference-signal sequence is uniquely defined for each resource element in the UE's reception, crucial for accurate channel estimation and subsequent data demodulation in 5G NR systems.