If you're unable to find a free PDF, you can consider purchasing the standard from SAE International or other authorized distributors.
Technical LibrariesLarge public or university libraries often carry physical or digital copies of SAE standards. While you may not be able to "keep" a digital copy for free, you can consult the document for research purposes. The Role of ARP 958 in Modern Engineering
In the field of electromagnetic compatibility (EMC) testing, accuracy is everything. Regulatory compliance requires precise measurements of radiated emissions and immunity. To achieve this, test laboratories rely on calibrated antennas.
Defining exact mathematical and physical methods to determine the Antenna Factor, which converts a received voltage into the corresponding electric field strength. sae arp 958pdf free
: Shielded rooms (though the standard itself does not account for the room's specific reflections).
Without an accurate, 1-meter calibrated AF, an engineer cannot reliably convert EMI receiver values into the valid electric field parameters demanded by high-stakes compliance standards, including:
: Used when two identical antennas are available. The gain is derived by measuring the insertion loss between them . If you're unable to find a free PDF,
For those seeking the core technical concepts without immediate access to the full document, the foundational calibration formula defined by the standard involves calculating the in a 50-ohm system:
Originally published in 1968 to standardize measurements for log-spiral antennas, SAE ARP 958 has evolved across multiple revisions—most notably and the latest ARP958E . It specifies the Three-Antenna Method and Two Identical Antenna Method to determine an antenna’s exact Antenna Factor (AF) within a near-field environment.
Research indicates that while ARP 958 methods are industry-standard, they can produce "ripple" in the calibration curve, potentially leading to 1–2 dB differences compared to other methods. The Role of ARP 958 in Modern Engineering
The aerospace industry relies on precise standards to ensure the safety, reliability, and calibration of critical testing equipment. One such foundational document is , which outlines the standard electromagnetic interference (EMI) measurement antennas calibration procedures.
Without a validated test site, EMC and antenna test data is essentially meaningless. If a test site has "hot spots" caused by signal reflections (multipath interference) or "nulls" caused by destructive interference, an engineer might incorrectly label a device as passing or failing a compliance test.