Performance evaluation of a LEO system in urban/suburban environments in ottawa, canada
Bibliographic record
Abstract
The performance of a LEO system (Globalstar) in downtown Ottawa (urban) and Bells Corners (suburban) was evaluated by predicting fade statistics using an expression that combined three statistical channel models into a single function and incorporated the average probabilities of being in a line-of-sight (LOS), shadowed or blocked path state to potentially visible satellites. The path-state probabilities were derived from a combination of digital hemispherical photographs taken in both environments with simulated look angles to the Globalstar satellites. Photo sets were taken at head-height, at above rooftop-height, and with the camera mounted on top of a van in order to simulate reception by pedestrian, residential, and mobile users. Fade cumulative distribution functions were calculated for every photo set, assuming operation with the single best satellite (in a LOS position) or the one with the highest elevation angle. A satellite diversity analysis found that substantial reduction in fade levels could be obtained by using this technique in downtown Ottawa and Bells Corners.
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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 | 0.001 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 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".