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Often, electromagnetic interference (EMI) scanning applications require phase and magnitude information for the creation of equivalent radiation models and far-field predictions. Magnitude information can be obtained using a spectrum analyzer (SA), which is relatively inexpensive compared to phase resolving instruments such as vector network analyzers (VNAs) and oscilloscopes at tens of GHz. This paper introduces and optimizes a cost-effective SA-based phase measurement method and compares the results to a VNA and oscilloscope-based methods for EMI signal sources. The measured-phase distribution obtained from the three different instruments is additionally compared with the simulated phase determined from full-wave simulation. The three measurement methods are compared based on the type of signal spectrum to be measured, such as single or multiple frequencies, signals requiring low-resolution bandwidth measurements, or transient signal events. The SA-based phase measurement technique is designed to operate from 5 to 12 GHz. However, the system frequency bandwidth is limited only by the frequency bandwidth of the individual RF components used in the SA measurement system.

Active cancellation of disturbing signals is a common method in EMC. In this paper, a specialized strategy is presented to minimize the disturbing harmonics of stationary clocked systems by injecting an appropriate harmonic cancellation signal with an adjustable signal synthesizer. The optimum cancellation signal is found via a convenient and robust adaptive approach. Each destructive harmonic is generated individually, and the cancelation signal is the superposition of a set of sinusoidal signals. As a special feature of this method, many troublesome effects, like delays or complex frequency characteristics, can be compensated easily. Several implementation variants can be derived from this general approach. Here, the variant, continuously adapted harmonics cancellation (CAHC), is considered. The system's limitations due to the ADC, the DAC, and the synchronization are described. An FPGA-implementation of CAHC is presented and applied to a dc/dc converter in an automotive component measurement setup to demonstrate the effectivity of the method.

This paper deals with the application of spread spectrum techniques on power electronic converters to reduce electromagnetic disturbances. These techniques aim for a spreading of the harmonics in a frequency domain in order to distribute the power over a wider frequency range. By doing so, the levels of the harmonics drop. In this paper, both peak and average detector measurements are considered. It is shown that different parameters are required to minimize either peak or average emissions. The reduction of peak and/or average emissions is mathematically described for a sine wave as a harmonic of pulse width modulation signals. These spread harmonics overlap for high orders and/or high-frequency variations. It is shown that this effect is a limiting factor for spread spectrum in practical applications. The resulting maximum achievable reduction is analyzed. From these results, parametrization strategies are derived to fulfill specific requirements. In test setups, the precision of the proposed parametrization strategies is demonstrated. Additionally, it is shown that the results for peak measurements can also be applied to quasi-peak measurements.

Power line communication (PLC) could not be established in automotive environments till now due to concerns with the unavoidable electromagnetic disturbances in the vehicle supply nets. Conducted broad band switching noise and field coupled narrow band noise can disturb the communication and prevent higher data rates. The continuously increasing size of the communication cable harnesses in vehicles is very difficult to handle, and PLC could reduce the complexity of the harness. This paper presents an approach to estimate the theoretical limits of PLC in the presence of noise in automobiles. Signal power and bit error rates are computed and discussed, based on electromagnetic compatibility-standards and PLC-parameter sets from older investigations’ noise levels. Commonly used automotive immunity tests are applied to analyze the signal to noise ratio of the PLC in a simulation environment. Therefore, immunity test setup models are introduced in order to analyze the noise injection and coupling characteristics to the PLC receiver. A virtual direct power injection (DPI) test is carried out with narrow band noise and transient pulse injection. For method validation, BCI measurements of a real PLC transceiver were carried out and failure behavior was compared to DPI simulation results. Immunity improvement for single carrier modulation in PLC is proposed. Finally, an analysis of the immunity to pulses is performed and results are discussed.

According to automotive standard CISPR 25, electronic components or modules are required to be connected to a specific test cable bundle in order to evaluate the radiated emissions. In the absorber-lined shielded enclosure (ALSE) method, also called the antenna method, the cable bundle is often the dominant radiation structure due to its length. This measurement method requires a large anechoic chamber, but often, it is only the impact of the test cable bundle's common-mode (CM) current distribution that is measured. Since the current distribution can be measured easily with current clamps, and with much lower demands to the environment, it is advantageous that the level of radiated fields can be estimated from the measured current distribution. This paper presents a field prediction method, which combines a measured CM current distribution with numerical computations for the radiated fields in the frequency range of 30–1000 MHz. Applicability is discussed based on several complex test cases. Three major problems had to be solved. First, appropriate current phase measurement methods had to be developed since the current amplitudes are not sufficient for estimating the electric fields. Second, a CM radiation model of a cable bundle had to be found. Third, in order to get comparable data for the ALSE test environment, a method had to be developed that could take this influence into account. Different solution approaches are examined here for the problems mentioned above.

In this paper, approaches for the modeling and simulation of thermal destruction of ICs due to ESD are discussed from a system point of view. Considered systems consist of ESD generator, PCB, protection element, and IC. A direct connection between the ESD generator and the system is always assumed. For the modeling of an IC ESD destruction, the electric behavior model of an IC pin to ground or supply is extended with a thermal destruction model. The thermal model consists mainly of a thermal resistance and a thermal capacitance. When structure temperature reaches a threshold, a failure is assumed. All needed model parameters can be found with a set of measurements and tests. No internal knowledge of the IC or protection element structures is required. The methodology was applied to several ICs, protection elements, and system structures with emphasis on automotive electronics. All needed component model parameters were generated from measurements. Models and parameter measurements are described. Results from the system simulation were compared to system test results with hardware. In most cases, the simulation could predict well the destruction behavior of a system. Thermal failure and safe operating area prediction quality are compared. The described simulation method helps with selection of protection strategies and optimization of system ESD robustness.

Computer simulation of electrostatic discharge (ESD) for simplified objects is described and compared to measured transient fields of human/metal ESD. The simulation algorithm uses the method of moments in time domain, coupled with nonlinear arc resistance model. Transient currents and fields are analyzed from the electromagnetic compatibility (EMC) point of view. Validation of the numerical simulation is done by comparison to experimental data. The simulated structure models the human/metal ESD in its peak current and field values and their derivatives reasonably well.