FCC Part 15 “Wireless” Pre-Compliance Testing
Test Capability Overview
- Radiated Spurious Emissions – Transmitter Harmonics can be measured quickly with automation software, a high speed 3-dimensional positioner, and a 40 GHz Rohde & Schwarz spectrum analyzer
- Radiated Spurious Emissions – Broad Band from 10 kHz to 18 GHz, as appropriate for your product’s transmit frequency
- Total Radiated Power TRP for confirmation of expected range and over-the-air performance (most FCC test labs cannot measure TRP, only EIRP)
- Antenna Efficiency by comparing to TRP to conducted power, to evaluate real-life antenna efficiency and matching without attached VNA coax cables
- Troubleshooting with specialized probes and tools, such as a 5 foot screen inside the anechoic chamber which can show analyzer levels and limit lines in real time
- Antenna Gain (or directivity) patterns in 2D polar cuts or full 3D spherical from 300 MHz to 40 GHz (there are many examples below, and very detailed example reports here), plotting software HERE.
Why Pre-Compliance Testing?
Example 12 shows many of the pitfalls of cut-and-paste reference designs
Many radio IC chipset manufacturers supply reference designs and even “eval kits” or “demo boards”. Cutting and pasting the reference design into another product is common, but often not without problems. If your product is not using a pre-approved radio module, then FCC testing and licensing is required. Pre-compliance scans for common FCC part 15.247 and 15.249 devices are very worth while! The first time failure rate is about 50% at formal test labs, with a test cost in the $4000 to $5000 range.
Experienced clients will use RTCE for pre-compliance testing, and often book troubleshooting time for on-site debug work to overcome product failures. Typical pre-scan costs are $450 for any small device which can be made to transmit with minimal effort. Our recommended design partners are HERE.