Realizing non-Foster reactances using negative-group-delay networks and applications to antennas
Bibliographic record
Abstract
Non-Foster reactive elements such as negative capacitors and negative inductors hold promise for a number of important applications such as broadband small antennas (beyond the Chu limit), broadband matching networks (beyond the Bode-Fano limit) and squint-free series-fed and leaky-wave antennas. Traditionally, negative capacitors and inductors have been implemented using negative-impedance converters (NICs) and negative-impedance inverters (NIIs). However, these NIC and NII circuits are prone to instabilities and excessive noise. In this article, we highlight a new perspective in realizing non-Foster reactive elements using negative-group-delay (NGD) networks. The underlying NGD networks are completely passive and thus stable. However, NGD are associated with some kind of loss (resistive or reflective) which can be compensated using amplifiers. The stable operation of these elements can lead to interesting antenna applications discussed in this paper.
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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 | 0.001 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.000 | 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".