RFG kit
An OATS or free space emissions measurement system essentially comprises of .....
- Emissions analyser with software
- Calibrated antenna
- Pre-amplifier
- Cables
In addition the key element is the test site. There are two key issues related to any site. These issues are:
- Ambient... The ambient is the background RF signals that are always present on any open site. The majority of these signals will be intentional from FM radio, TV, mobile phones, telemetry, emergency services etc... Many of these transmissions are erratic. There are also many sources of unintentional transmissions, for example from all types of electronic equipment, motors, lighting, power supplies etc.... The Laplace EMCEngineer software features a technique for measuring this ambient and then subtracting it from the EUT measurements. Although this sounds simple, in practice it requires some careful processing.
- Test site calibration.... The key issue here is reflections. 'Proper' EMC test techniques require a site free of reflections (apart from the ground plane). In most cases this is impractical and so Laplace has developed a technique which uses an ERS (Emissions Reference Source) in conjunction with the EMCEngineer software to calibrate the test site. By using this technique, measurement uncertainty is substantially reduced.
Therefore, a recommended option for RFG kits is the ERS.
As regards the ambient, there are two specialised filters that are fitted in the connection to the antenna. These are:
- RF600, an FM band notch filter, which attenuates signals in the range 80MHz - 115MHz, thus preventing any strong FM signals affecting measurements.
- RF700, 30MHz high pass filter, which blocks all signals below 30MHz. This is most useful as (in general) there can be high levels of RF noise at these lower frequencies which can cause compression issues in the analyser. Because the radiated emission bands start at 30MHz, attenuating these lower frequencies improves performance without affecting any measurements.
| Item | SA1002 | SA3000 3GHz |
Analyser | RFG- | RF3G- |
| RF200 Broadband antenna 30MHz - 1GHz | -B | -B |
| RF230 Broadband antenna 700MHz - 3GHz | -B2 | -B2 |
| RF300 large loop antenna | -L | -L |
| ERS, Emissions Reference Source | -C | -C |
| RF600, FM band filter | -F | -F |
| RF700, 30MHz high pass filter | -H | -H |
Example of a complete kit including | RFG-BCH | RF3G-BB2C |
Other items such as ancillary items for conducted emissions (LISNs, Pre-selectors etc...) can be added as required. See conducted kits for item codes.
Features
- Fully integrated systems
- includes powerful windows software package
- USB interfaced to your PC
- 1GHz or 3GHz versions available
- Check emissions as required by EN55022, EN55011, EN55014, FCC and many other standards
- Compare measurements directly with the limits
- Study the effect of modifications
- Can be used for pre-compliance or self-test, self certify purposes
- Emissions reference source correlates your results against a calibrated test site
- Near field probes included for inverstigative tasks
RFG kit provides the following products:
1GHz EMC emissions AnalyserThe SA1002 is a fully featured EMC emissions analyser for all EMC compliance measurements up to 1GHz
3GHz EMC emissions AnalyserHigh performance, PC controlled, 3GHz EMC analyser with powerful Windows software application.
Antennas for EMC testing (optional for this kit)Antennas are normally required for the measurement of radiated emissions. Laplace offers a wide range of antennas to suit the various requirements. These include standard broadband antennas, miniature antennas and Large Loop Antennas.
Emissions Reference Source (ERS) (optional for this kit)The ERS is a transfer standard for the calibration of radiated emission measurements on OATS or in EMC chambers.
Ancillaries - Radiated (optional for this kit)Ancillary items that can make all the difference when measuring EMC emissions. These include pre-amplifiers, filters and near field probes.
Active near field probes (optional for this kit)Active probes are ideal for source location and for the detection of low level emissions. The CTK kits include cables, connectors, manuals and carry case.
LISN & Voltage Probes (optional for this kit)These ancillaries enable compliant conducted emission tests. A wide range of LISNs plus voltage probe are available.
Pre-Selectors for EMC test (optional for this kit)Pre-Selectors are an essential requirement if measuring conducted emissions that have high broadband noise content. They effectively convert an EMC Analyser into a receiver, as specified by CISPR16.
See Technical Paper for a fully explanation of pre-selectors and why they are important.