Radiated Emissions Testing
Ensuring your product does not exceed test limits (FCC, CISPR, etc) is the manner incorporated in North America to minimize RF interference among electronics.
Testing for radiated emissions is done in a couple formats. Primary, is by using antennas to measure what is emitted directly from the product under test. Secondary, is to measure power and data lines using clamps around the cables to measure emissions emitted down power or data lines.
EMC Radiated Emissions
Performing precompliance EMC testing for radiation emissions is common to do throughout the design process. While replicating an EMC test lab is a challenge, most of our customers will setup an RF tent to isolate noise while testing their product. After setting up a directional antenna and connecting to a spectrum analyzer, they are off and rolling. Test standards can provide specifics regarding spacing, insulation, placement , etc... We have found that in most cases, these aren't detrimental pieces to getting reliable emissions measurements. Most EMI software will have the test levels pre-programmed for common radiated emissions test standards.
Materials & Test Equipment
- Analyzer or monitor - Frequency range or specific, sweep
- Absorbing clamps
- RF field probes - directional or spherical
- Extension cable for long distance measurements
The EMC Shop supports radiated emissions setup and testing.
Taking radiated emissions on very large equipment such as industrial machinery or other equipment that is already installed - see In-Situ Testing
Radiated emissions testing on small products can be performed in small benchtop enclosures. See the video section for an example.
EMC Radiated Emissions Test Setup
Ensure to take baseline measurements to ensure you are identifying issues emitted by your product and not an external factor in your lab.
For FCC Part 15, your test frequency range is determined by the fastest clock speed of your product. Beyond 1 GHz, your limit will be the same.