Spectral occupancy of fixed and mobile allocations within the high frequency band
Bibliographic record
Abstract
Power levels in the High Frequency (HF) band from 3 to 30 MHz were measured to determine channel occupancy statistics including patterns in time and frequency. Congestion in Canadian spectrum allocations for fixed and mobile users and patterns in the ambient radio noise power across the HF band were examined. A receiver site was set up in Ottawa, Canada using a spectrum analyzer and an omni-directional, horizontally polarized antenna having an elevation pattern optimized for reception of signals arriving via sky wave propagation. Diurnal and random fluctuations in channel occupancy, congestion, and noise measurements were observed and sample data plots for fixed and mobile allocations were presented and discussed. The availability of unoccupied channels in bandwidth increments of 3, 12, and 24 kHz for each 1 MHz frequency range is discussed and may be used to inform future assignments for fixed and land mobile services in the Canadian Table of Frequency Allocations. Hourly variations in channel occupancy show that there are ample spans of contiguous unoccupied spectrum to support channel bandwidths up to 24 kHz during most hours of the day; however, during the most congested times, even 3 kHz contiguous channels are not available in the frequency ranges that are optimal for propagation. These results suggest that spectrum availability in the region can support the use of wideband HF modems; however, the optimal modulation bandwidth will vary according to the time of day and the number of channels required.
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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 | 0.000 |
| 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".