Ultrawideband monopulse antenna with application as a reflector feed
Bibliographic record
Abstract
A novel ultrawideband pattern diversity antenna, with sum and difference radiation patterns used in monopulse tracking, is proposed. To achieve pattern diversity, a crescent‐shaped radiating element is fed from two sides at an angle close to 90°, by two coaxial feeds. The ground is a corner‐shaped cavity. The sum and difference patterns can be obtained by in‐phase and out‐of‐phase excitations of the two coaxial ports. A single‐element antenna is first studied to show the operating principle of the design. A modified design with two elements is then proposed and studied through simulations and measurements of a fabricated prototype, showing excellent radiation characteristics over a large frequency bandwidth. The application of this antenna as a reflector feed is then studied. It is shown that the antenna can theoretically feed a prime focus reflector with 60% (for the sum pattern) efficiency over a 48% fractional bandwidth (5.5–9 GHz), with a maximum efficiency of 75%. The antenna is compact (5 × 4.1 × 2 cm 3 ) and has low cost and simple fabrication. To the best of authors’ knowledge, this is the first attempt to feed a reflector with this class of antennas.
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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) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.001 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.001 |
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".