Implementation of a combination planar and spherical near-field antenna measurement system using an industrial 6-axis robot

Near-field antenna test systems are typically designed to optimize measurement results for a specific type of antenna. The measurement system is selected and sized based on the antenna aperture dimensions, directivity, weight and operating frequency, among other parameters. These factors are used to select either a planar, cylindrical, or spherical near-field test system for the given antenna test requirements. Antennas with different characteristics may not be compatible with the selected range and often require costly upgrades to the existing range or a different range altogether. One solution to test a wide variety of antenna types is a combination planar-cylindrical-spherical (PCS) test system. These systems usually require some level of facility re-configuration and present drawbacks when switching between the various modes of operation. The adaptation of a six-axis robotic test system is an attractive solution in these situations, as the system's flexibility allows for rapid reconfiguration that is inherent to the system. This allows the user to select the optimal test solution for the antenna under test with little effort. This paper presents the performance of a six-axis robotic near-field measurement system showing near-field modes of operation and the system's performance in antenna measurements when compared to a traditional spherical near-field range.