Whitepaper
Using Periodic Calibration of Antennas to Ensure the Ongoing Performance of OTA Systems
This Keysight Technologies white paper makes the case for regular, professional antenna calibration as a critical component of any over-the-air (OTA) system's long-term reliability. It begins by distinguishing between the two main antenna types — narrowband (such as dipoles and standard-gain horns) and broadband (such as biconicals and log periodic antennas) — noting that both require real-world measurement rather than purely mathematical modeling to accurately determine gain and radiation patterns. The paper then outlines the key performance attributes used to characterize antennas: gain factor, radiation pattern, voltage standing wave ratio, polarization, and beam width. A central focus is the hidden physical and electrical issues that degrade antenna performance over time, illustrated with insertion loss data comparing good and faulty waveguides, showing average deviations of nearly 2 dB. The paper argues that accounting for these losses reduces measurement uncertainty, improves calibration accuracy, and mitigates potential performance failures. It concludes by promoting Keysight's Iowa Center of Excellence, which has over 30 years of experience providing accredited, standards-compliant calibration services across ANSI, CISPR, IEEE, MIL-STD, and SAE standards, supported by the world's largest open-area test site.