rom the time that Heinrich Rudolf Hertz first demonstrated the transfer of electrical energy from one antenna to another in the late 1880s, humanity has witnessed, observed, and enjoyed the fruits of electromagnetic radiated fields. The electromagnetic waves first produced by Hertz in his lab in 1886 were proof that James Clerk Maxwell’s 1864 theory of “electromagnetic waves” was correct.

Hertz published a series of papers in the last years of the 1880s that verified the characteristics of the “Hertzian Waves” with respect to frequency, amplitude, speed (velocity of light), and other physical parameters. Hertz never realized the practical importance of his discovery and did not explore the applications of the “Hertzian Waves,” which became known as “radio waves” over time.

However, many premier scientists of the day did recognize the importance of the discovery, including Guglielmo Marconi, Nikola Tesla, Edwin Armstrong, Lee DeForest, and many others.

aval platforms present the most severe Electromagnetic Environment (EME) in the world, created by high-powered electromagnetic emitters such as air-search, surface-search, fire-control, and navigation radars, as well as broadband communications and electronic warfare systems. The limited space available aboard surface platforms necessitates that these high-powered electromagnetic emitters be located in proximity to other electronic/electrical systems aboard ships. Sensitive electronic equipment is typically contained within Radio Frequency (RF) reflective cavities (i.e., below-deck spaces, equipment enclosures, etc.) for protection from harsh EMEs. Communications and power cables are typically routed between enclosures within such spaces, introducing inadvertent coupling paths between cavities. Additionally, as the topside EME continues to increase and as below-deck transmitters (i.e., RFID, Wi-Fi, etc.) are incrementally installed within the Fleet, understanding and predicting the field distributions within coupled spaces will assist in characterizing electronic equipment performance and assuring personnel safety.

Statistical electromagnetic formalisms for electromagnetic fields within RF-reflective cavities had their beginnings through the study and use of reverberation chambers (RCs) for Electromagnetic Compatibility (EMC) testing [1] and are now widely accepted within the EMC community as a tool for compatibility and susceptibility testing [2-4]. RCs are electromagnetically reflective cavities with a high quality (Q) factor where the fields excited within the cavity reverberate [4-6]. The addition of tuners within the chamber (also known as paddles or stirrers) allows for the electromagnetic (EM) boundary conditions to be easily changed so the EM fields can be perturbed discretely (mode-tuned) or continuously (mode-stirred).

n the age of digital health, connected medical devices are transforming patient care. From insulin pumps and glucose monitors to smart inhalers and wearable ECGs, these devices deliver real-time data, enable remote monitoring, and improve clinical outcomes. However, as connectivity increases across devices, so does the risk of cyber attacks. For engineers tasked with designing these devices, security by design is more imperative than ever for compliance.

Consider a scenario in which a hacker exploits a vulnerability in a Bluetooth-enabled insulin pump. The attacker could alter dosage settings or disable alerts, putting the patient at serious risk. Such vulnerability issues are made possible due to the increased entry points from devices,² leaving those who use clinician-recommended technologies for care susceptible to attacks.

hether you’re trying to get a product through safety approval from one of the many Nationally Recognized Testing Laboratory’s (NTRLs) or having full compliance EMC testing performed at an accredited or non-accredited third-party laboratory or an internal in-house test facility, it’s imperative for successful completion of the project that as a compliance engineer or technician leading a product certification effort, you trust but verify the work of these other entities. For the remainder of the article, we’ll call these other entities “service providers.”

If investing in a new system isn’t the right move right now, NSI-MI’s Test Services offer a powerful alternative. You’ll gain access to the same advanced technology, precision environments, and expert support—without the upfront commitment. Our dedicated test service facilities are designed to deliver consistent, high-quality results, helping you move projects forward with confidence. With controlled conditions and expert oversight, we ensure your measurements are not only accurate—but truly meaningful.

Our advanced test ranges include:

• Compact Antenna Test Range (Atlanta, GA): Ideal for multi-purpose and far-field measurements, supporting frequencies from 2 to 50 GHz and devices up to 1.8 meters in diameter.
• Combo Near‑Field Range (Los Angeles, CA): A versatile system supporting planar, cylindrical, and spherical near-field testing from 1 to 110 GHz, accommodating devices up to 3.6 meters.
• Spherical Near‑Field Ranges (Los Angeles, CA): Covering frequencies from 300 MHz to 110 GHz, these ranges are optimized for high-precision measurements of complex antenna systems.

Whether you’re validating phased array performance, calibrating near-field probes, or preparing for terminal operations certification, NSI-MI is your trusted partner for RF testing. We specialize in the characterization of antennas, radomes, and RF devices across a wide range of industries including aerospace, defense, wireless, and automotive.

Don’t leave your RF performance to chance. Partner with NSI-MI for reliable, high-precision testing.

Element Materials Technology operates advanced battery testing labs offering comprehensive services for batteries used across industries like automotive, aerospace, consumer electronics, medical devices, and energy storage. These labs ensure batteries meet stringent safety, reliability, and performance standards, especially for lithium-ion, lithium-metal, and solid-state technologies.

With facilities worldwide, Element provides testing close to manufacturing and distribution hubs, enhancing efficiency and speed to market. By tailoring testing programs and guiding clients through certification, Element helps companies deliver safe, reliable, and high-performance battery solutions for global markets.

Contact:
contact.us@element.com
(888) 786-7555
https://www.element.com/connected-technologies/battery-testing-services

Our lab specializes in the characterization of static dissipative properties for products and materials, adhering to all major ESD standards—including ANSI/ESD, MIL-STDs, IEC, and other internationally recognized benchmarks. This ensures that materials used in manufacturing and handling meet critical ESD control requirements, providing essential protection for sensitive electronic devices.

A cornerstone of our capabilities is product qualification testing in accordance with ANSI/ESD S20.20. This is performed within our ISO 17025-compliant laboratory, featuring calibrated ESD test instrumentation, temperature- and humidity-controlled gloveboxes, and a dedicated controlled environment room. Our processes are carried out by highly trained technical personnel who ensure precision, repeatability, and compliance at every stage.

In addition, we offer reliability and ESD susceptibility testing of devices and systems using Human Body Model (HBM), Charged Device Model (CDM), and Machine Model (MM) simulators. These tests are vital for compliance assessments, failure analysis, and design verification, and are conducted in alignment with ANSI/ESD and JEDEC standards. This helps clients identify vulnerabilities early and validate robustness under realistic ESD scenarios.

Our team of experienced ESD Program Managers and ESD Electrical Engineers brings a unique level of customization to every project. From consumer healthcare products like nasal gel to complex aerospace hardware such as satellite components, our staff tailors evaluations to the specific needs of your application. We pride ourselves on being a collaborative partner throughout the testing lifecycle—offering not only results but insight and guidance.

Through a combination of accredited processes, specialized environments, and industry-leading expertise, our test lab plays a pivotal role in ensuring product integrity and performance in ESD-sensitive environments. Whether for compliance, R&D, or product development, our lab delivers trusted results that support innovation, reliability, and customer assurance.

Contact:
Lisa Pimpinella
info.eosesda@esda.org
(315) 339-6937
https://www.esda.org/eosesd-association-services-llc

his is the third of seven articles devoted to the topic of shielding to prevent electromagnetic wave radiation. The first article [1] discussed reflection and transmission of uniform plane waves at a normal boundary. The second article [2] addressed normal incidence of a uniform plane wave on a solid conducting shield with no apertures. The article concluded with the definition of shielding in the far field given by

A uniform plane wave is normally incident on its left interface. Uniformity assumption, together with normal incidence, means that the shield is in the far field of the radiation source.

The incident wave, upon arrival at the left most boundary (), will be partially reflected () and partially transmitted () through the shield.

he new connector standard USB-C includes both power delivery of current up to 20 V as well as SuperSpeed data lines. Integrated circuits (ICs) receiving signals on these data lines are very ESD sensitive. The Vbus pins in the USB-C connector are placed directly next to the SuperSpeed Tx and Rx pins, which poses the risk that the data pins can temporarily short to the supply voltage. The USB-C specification requires a mandatory AC coupling capacitor placed on the data lines in front of the IC when USB4 is used on the SuperSpeed lines. Thus, transient voltage suppressor (TVS) devices for system-level protection can be placed either behind the AC coupling capacitor or in front of it.

In this article, the effect of the TVS placement and the device properties on the IC is investigated. Special PCBs have been produced; one is shown in Figure 1. The distance between TVS and an IC replacement consisting of a 2-ohm resistor and a forward-bias diode is varied. The voltage at the IC can be measured. The IC residual current is determined by measuring the voltage drop across the resistor. Six different TVS protection devices have been chosen. All of them have a capacitance of less than 0.2 pF, which makes them suitable for the SuperSpeed application. Two of them are placed in front of the capacitor. However, to avoid turning on during a short to the power line, these TVS devices require a breakdown voltage larger than 20V. For a placement behind the capacitor, a high breakdown voltage is not needed. An overview of the TVS parameters is shown in Table 1.

recently heard an amusing quote from a colleague: “When it comes to EMC simulation, no one believes the results—except the person who did the simulation. When it comes to EMC testing, everyone believes the results—except the person who ran the test.” Anyone who’s worked in the field of EMC will probably smile knowingly at that.

Thanks to advancements in simulation tools, it’s now possible to build fairly accurate models using 3D solvers to simulate conducted emissions, radiated emissions, surface currents, and more. But such simulation tools come at a price—not only in terms of expensive software licenses (which often puts them out of reach for small to medium-sized companies), but also the steep learning curve. Whoever runs these simulations needs to thoroughly understand the product and its circuitry—including parasitics, physical layout, and component behavior—and must also be skilled in building the simulation model itself. A good model can take weeks, even months, to develop. And after all that effort, how do you validate it? You still need test results to back it up.

As a practical engineer, I often lean more toward hands-on diagnostics. To paraphrase a well-worn saying: “My best simulation tool is my soldering iron.” (Though in the EMC world, maybe we should say: “My best simulation tools are my near-field probes and current clamps.”)