Standardized Test Methods in Over-the-Air Chambers for FCC Part 27

Abstract: Base stations (BSs) are the cornerstone that enables wireless communications. In order for a new BS variant to be imported and sold in the US they are required to undergo electromagnetic compatibility (EMC) testing. This testing is necessary to obtain their Federal Communications Commission (FCC) certification. At the EMC verification department at Ericsson Kista tests are performed to verify compliance with FCC Part 27 regulations. These tests are currently performed by detaching the antennas of their advanced antenna system (AAS) and connecting between each antenna port and measurement equipment with cables, according to standardized procedures. The objective of this work was to investigate over-the-air (OTA) test methods of interest for standardization, present results according to the methods, and implement visualizations for the results. A literature review was performed on existing standardized OTA procedures. Measurements were analyzed and evaluated from an anechoic chamber and compact antenna test range. Spurious emission measurements were performed in a reverberation chamber (RC) adhering to the regulations and standardized procedures. MATLAB was employed to develop 3D visualizations for measurement data. The work highlights how several test cases in the regulations can be performed OTA. The study concludes that the RC is the preferred test methodology for evaluating total radiated power based on measurement time and simplicity. The results are intended to aid the EMC verification department in their discussion with the FCC regarding standardized OTA procedures towards FCC Part 27. Moreover, the implemented 3D visualizations hold potential for future OTA testing application within the EMC verification department and serves as an example for similar projects.