Question: In the context of User Equipment (UE) / Mobile Station (MS) Over The Air (OTA) antenna performance, how is the Total Radiated Power (TRP) primarily defined for conformance testing in an isotropic environment?
Option 1: As the average value of statistically distributed samples of radiated power, calibrated against a reference power transfer function to obtain an absolute TRP value.
Option 2: Directly through the integral of power transmitted in different directions over the entire radiation sphere without calibration.
Option 3: By measuring the maximum power output of the UE/MS in a single direction and extrapolating to all directions.
Option 4: Through the calculation of path loss in cables connecting the measurement receiver to fixed measurement antennas.
Explanation: In an isotropic Rayleigh fading environment, TRP is effectively measured by sampling the radiated power for multiple field combinations, averaging these samples, and then calibrating this average against a known reference power transfer function to derive the absolute TRP value. This method accounts for the variability in power transmission across different directions, providing a comprehensive measure of the UE's/MS's radiated power capability.