HARDWARE EXPERIMENTS & DEMONSTRATIONS
Tuesday, March 17 – 2:00 PM – 4:00 PM
Topic: ETSI EN 300 328 V1.8.2 and ETSI EN 301 893 V1.7.2 Clarified Requirements and Synchronized Power Sensor Demonstration
Presenter: Jack McFadden, ETS-Lindgren, Cedar Park, Texas, USA
The ETSI EN 300 328 V1.8.2. Electromagnetic compatibility and Radio spectrum Matters (ERM); Wideband Transmission systems; Data transmission equipment operating in the 2,4 GHz ISM band and using wide band modulation techniques; Harmonized EN covering the essential requirements of article 3.2 of the R&TTE Directive and ETSI EN 301 893 V1.7.2 Broadband Radio Access Networks (BRAN); 5 GHz high performance RLAN; Harmonized EN covering the essential requirements of Article 3.2 of the R&TTE Directive has further clarified their power measurement requirements.
The ETSI explained its definition of conducted method of simultaneous data acquisition for multiple input/multiple output products (MIMO). The conducted power measurements are required to be made using synchronized (simultaneous) sensors. The minimum sampling speed of the data acquisition system is 1 Mega-Samples per second with the minimum sample of all sensors to be less than 500 nanoseconds.
The ETSI 300 328 V1.8.2 was published in April 2014 and ETSI EN 310893 V1.7.2 was published in July 2014. The compliance dates are 18 months after their release.
This demonstration is created to enable the viewer to understand the ETSI EN 300 328 V1.8.2 and 301 893 V1.7.2 clarified requirements as well as show how synchronized power sensors meet the ETSI power measurements.
Wednesday, March 18 - 9:00 AM – 11:00 AM
Topic: Inductive Effects in Cables
Presenter: Jerry Meyerhof, JDM Labs LLC, Buffalo Grove, Illinois, USA
The laboratory objective: Understand the practical implementation details of "cables" or "transmission lines" which are critical to EMC performance, as used between modules/units, across systems and within Printed Circuit Boards (PCBs).
1) Signal currents follow the path of least impedance.
2) Cable geometry effects and self-shielding.
3) Conversion mechanisms between differential and common mode signal propagation.
4) Impact of cable mechanical end termination geometry such as "pigtail" connections.
5) Use of Common-Mode Chokes.
Analyze and Predict the observed effects
Another element of the presentation is to talk about the tasks involved in getting an educational lab to work, much like the Chris Semanson article in our EMCS magazine and his own demos in past years.
Wednesday, March 18 - 2:00 PM – 4:00 PM
Topic: Consideration on the EM Noises Before and After the Regular Tests from ESD Generator
Presenters: Makoto Sugihashi, Noise Laboratory Co., Ltd., Kanagawa, Japan
Tony Tokuya, Shinyei Corp of America, New York, NY, USA
Electrostatic discharge (ESD) generators cause electromagnetic (EM) noises not only at ESD tests but also even before and after the tests. These phenomena may cause the unexpected test results. To explain the mechanism qualitatively, we investigated a generation source model of EM noises from an ESD generator.
Topic: Minimizing magnetic field susceptibility through the proper use of static and low frequency magnetic shielding
Presenters: Pablo Narvaez and Nelson Huang, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
The Jet Propulsion Laboratory has participated in multiple projects whereby implementation of proper magnetic shielding has been a key component in successful space missions free of static and low frequency magnetic interference. This hardware experiment/demonstration presents magnetic shielding methods similar to those applied on JPL hardware for typical magnetic cleanliness programs.
Thursday, March 19 – 9:00 AM – 11:00 AM
Topic: Radiated Emissions as a Function of Common Mode Current
Presenter: John McCloskey, NASA/Goddard Space Flight Center, Greenbelt, MD, USA
For any product, an essential part of EMI testing is the radiated emissions test. However, it is often the case that product development engineers, concerned with more visible design problems, ignore EMI concerns until the very day they take their boxes to an EMI test facility for radiated emissions testing, and then are terribly shocked when they find that they’ve failed.
At frequencies below about 200 MHz, a significant portion of the radiated energy originates from uncontrolled common mode currents on cables connected to the unit. The product development engineer may perform an early assessment of radiated emissions by directly measuring these currents.
In this demonstration, a controlled current is applied to a wire above a ground plane, and the resulting electric field is measured. The transfer function of electric field per unit current (E/I) is determined and presented as a tool for predicting radiated electric fields from a simple measurement with a clamp-on current probe before the product ever leaves the development laboratory. Product development engineers are encouraged to perform these measurements in order to facilitate diagnosis of potential problems as early as possible in the product's development cycle.