Variable coupler for Butler beam-forming matrix with low sidelobe level
Bibliographic record
Abstract
A Butler beam-forming network with low sidelobe level (SLL) is proposed and demonstrated on the basis of variable couplers. A set of couplers with 0.75, 1.26, 3, 6 and 8 dB coupling levels are required to achieve an SLL of −13.6, −20 and −30 dB. Such variable coupling is achieved by creating a movable mirror structure in the common region of perpendicularly or cross-coupled waveguide building blocks. This mirror is composed of a 5×7 cylindrical rod array. The coupling and directivity characteristics depend on the position of this proposed fringe structure. In this work, WR28 is used to demonstrate the capability of this type of coupler over 26–30 GHz bandwidth. Structure usefulness and design procedure are validated by electromagnetic simulation high frequency structural simulator (HFSS) and prototype experimentation. Very good results are observed, that have also demonstrated attractive performances of the coupler. Measured results of couplers are used to assess the properties of Butler matrix with excitation coefficients corresponding to −13.6, −20 and −30 dB of SLLs. Radiation patterns obtained by this investigation show a promising performance. This proposed technique allows flexibility in the choice of excitation coefficients without degradation on the efficiency.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| 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 | 0.000 | 0.001 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 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 teacher head, 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".