Wave Propagation in 1D EBGs: Periodic Multilayer Films Consisting of Two Different Materials [This Issue's Contribution]
Bibliographic record
Abstract
This paper presents the fundamental concept of wave propagation in periodic multilayer films consisting of two different materials, so-called one-dimensional electromagnetic bandgap (EBG) materials. To this end, Floquet's theorem is first presented. Next, the transmission-line analogy is used to simplify the concept of wave propagation in one dimension. The Bloch impedance concept is then presented, and its usefulness is illustrated in the applications of truncated periodic structures. Through a few case studies, it is shown that the ripples usually appearing in the pass band of the EBGs are due to the mismatch of the transmission-line ports. When the EBG structures are terminated to appropriate Bloch impedances, the ripples disappear. The material can be used in undergraduate or graduate "Microwave Engineering" or "Advanced Engineering Electromagnetics" courses. The students need to know about the ABCD matrix in advance. The material helps students in better understanding of microwave filters, and shows the importance of matching the terminal ports and number of unit cells. Students can use software packages such as MATLAB to obtain the Bloch impedances, and such as Ansoft HFSS to reproduce the scattering parameters presented in this paper. The materials in this paper are consistent with those in [3, 7, 8, 9] and, in some cases, are summarized from these references to improve the clarity.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.001 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".