Question: What is the primary purpose of using an omni-directional antenna when evaluating the quiet zone reflectivity level in an anechoic chamber for UE/MS OTA antenna performance conformance testing?
Option 1: To enhance the direct signal strength from the antenna under test.
Option 2: To accurately measure the contributions of absorbing materials and constructions within the chamber.
Option 3: To minimize cable effects on measurement sensitivity.
Option 4: To ensure comprehensive capture of reflected signals in all directions for accurate quiet zone quality assessment.
Explanation: An omni-directional antenna is utilized to ensure that all reflected signals within the quiet zone are captured comprehensively, regardless of their direction. This is crucial for accurately assessing the quality of the quiet zone by evaluating the reflectivity level, which is defined as the power ratio of all summed reflected signals to the direct signal from the antenna. While options 2 and 3 mention aspects related to the evaluation process, they are not the primary purpose of using an omni-directional antenna in this context. Option 1 is incorrect as enhancing the direct signal strength is not the primary goal here.