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A method for extracting the effective copper surface roughness of a laminate in situ is introduced. The rough copper attenuation as a function of surface roughness is removed from the total attenuation. The residual loss is fit to coefficients, and an error is calculated based on the remaining apparent surface roughness contribution. When the error is minimized or when the apparent surface roughness contribution is nearest zero, the effective surface roughness is found, and the dielectric attenuation is isolated by subtracting the rough copper attenuation from the total attenuation. Using this value, accurate broadband permittivity values can be extracted by simply measuring the S-parameters of two stripline transmission lines. Further, the extracted dielectric electrical properties are calculated with a higher accuracy than the existing methods that neglect copper surface roughness. A supplementing method to unwrap the phase constant is also included in this work to avoid errors do to the length of the devices. Previous methods of extracting laminate material properties that consider copper surface roughness rely on cutting the sample to make a cross-section and observe the surface roughness directly. In this work, the effective surface roughness is gathered without destroying the sample.

This study deals with an electromagnetic compatibility (EMC) problem of fiber cable in disturbing electric field. Lightwaves that emerge from the output endface of the fiber are intensity modulated, phase shifted, or modulation frequency multiplied under special conditions. In this paper, theoretical investigation of the effect of interfering electric fields on the bit error rate of digital signals propagating originally in an optical fiber is presented for the EMC evaluation. Theoretical analysis and specific numerical examples show that depending on the required EMC level, the unshielded fiber may not be immune to interference of electromagnetic fields.

A method of determining electromagnetic interference shielding effectiveness of various cases has been developed using a modeling technique where radar cross section (RCS) is used in the calculation of shielding effectiveness and a planar wave is utilized to model mode stirring in the reverberation chamber. In addition, a new shielding effectiveness equation is derived in terms of RCS. Three different test cases based on the small form-factor pluggable family are measured and compared to the simulation results based on the derived shielding effectiveness equation. The measurement and simulation results are plotted and compared to validate the proposed modeling methodology. It was found that results from the measurement and simulation are in good agreement and the simulation method is validated.