Question: In E-UTRAN Downlink Positioning, what additional information is utilized alongside UE measurements of downlink radio signals from multiple Transmission Points (TPs) to estimate the UE's position?
Option 1: UE's uplink transmission power and antenna configuration
Option 2: Geographical coordinates of the measured TPs and their relative uplink timing
Option 3: Cell ID and neighboring cell signal strengths
Option 4: Geographical coordinates of the measured TPs and their relative downlink timing
Explanation: In downlink positioning within E-UTRAN, accurately estimating a UE's location relies on measurements of downlink signals from multiple TPs, plus knowing the TPs' physical locations (geographical coordinates) and their relative downlink timing. This is crucial for calculating distances or time of arrival differences to triangulate the UE's position.