Comparison of Butler Matrix and Rotman Lens Beam-Switching Networks at K-Band
Bibliographic record
Abstract
This paper presents a comparative study between an$8\times 8$Butler matrix and an$8\times 8$Rotman lens operating over K-band (24.25 GHz to 27.5 GHz). The Butler matrix is designed based on aperture hybrid coupler and Schiffman phase shifter and printed on a multilayer stack-up to eliminate all the cross-overs and therefore, reduces the size and the insertion loss of the system. The Rotman lens has 8 inputs, 8 outputs, and 2 dummy ports and is designed to provide$\pm 45^{{\circ}}$scanning range over the desired frequency band. Both beam-switching networks show less than −10 dB return loss over 24.25 GHz to 27.5 GHz. The designed$8\times 8$Butler Matrix presents less insertion loss and a more compact size compare to the$8\times 8$Rotman lens. However, the plotted Array Factor (AF) using the achieved output phase of each network proves that the Rotman lens is True Time Delay (TTD) while beam squint is an inherent characteristic of Butler Matrix.
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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) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 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".