Further analysis of the second-order high frequency radar ocean surface cross section for an antenna on a floating platform
Bibliographic record
Abstract
When the transmitting and/or receiving antennas of a high high-frequency (HF) radar are mounted on a floating platform, which is subject to sway, it is known that motion introduces additional features in the Doppler spectra of the signal scattered from the ocean surface. Following techniques in earlier work which examined these features up to second order for scatter from a patch of ocean remote from the antennas, we consider second-order effects arising from a single scatter near the antennas followed or preceded by a scatter on the remote patch. The derivation begins with a general expression for the bistatically received second-order electric field in which platform sway is introduced. This is then reduced to the monostatic case. Having developed the monostatic equations, and assuming the ocean surface to be representable as zero-mean Gaussian process, the corresponding second-order monostatic radar cross section (RCS) is developed. As in the earlier analyses for patch scatter, the new contributions to the RCS appear as Bessel functions, which give rise to extra spectral content not appearing in the fixed-antenna results. However, simulations of the new RCS, including antenna sway under a variety of sea states, suggest that while the new second-order effects are visible in the spectrum, they are generally smaller than first-order effects, except at specific Doppler frequencies.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
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 | 0.001 |
| 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) | 0.001 | 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".