Real-time Spectrogram of 20 GHz Bandwidth Frequency Hopping Signals using a 6 GHz Detector
Bibliographic record
Abstract
A joint time-frequency representation of a microwave or RF signal, such as a spectrogram, gives critical and intuitive information about how the signal spectrum evolves over time. This is crucial for radar, sensing and ranging, wireless spectrum monitoring, and cognitive communications. The Talbot Array Illuminator Spectrogram (TAIS) is a photonic signal processing scheme that computes the spectrogram of continuous microwave signals in real-time without gaps in acquisition. In this work, we experimentally demonstrate how the TAIS can be used to recover the real-time, gapless spectrogram of a frequency hopping signal with nanosecond hopping speeds on 20 random channels spread across a microwave bandwidth of 20 GHz using a 6 GHz photodetector. The use of a lower bandwidth acquisition system facilitates the practical implementation of the TAIS while dramatically reducing the cost of this signal processing scheme.
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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 | 0.001 | 0.000 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.001 | 0.002 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| 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 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".