A unified framework for the construction of OFDM/OQAM systems
Bibliographic record
Abstract
OFDM/OQAM is a promising radio access technique for high data-rate fourth generation cellular systems, operating on time and frequency dispersive wireless channel. Contrary to the well established OFDM/QAM, it allows very well localized prototype waveforms to be used for critical unit-density time-frequency lattices, offering maximal spectrum efficiency. Starting from the set of orthonormality conditions verified by the frequency-time lattice shifted versions of the prototype waveform, we derive the general orthonormality criterion for OFDM/OQAM. We show that even and odd parity prototype waveforms are basically the unique waveforms for which the general orthonormality criterion simplifies to that of OFDM/QAM with frac12 time-frequency lattice density. Based on the simplified criterion, we propose and characterize a new orthonormalization procedure for the efficient design of very well localized prototype functions, starting from non-orthogonal mother waveforms. Finally, we show that odd parity orthonormalized mother functions lead inevitably to badly localized prototype waveforms and that only even parity prototype waveforms should be used in practice.
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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 | 0.001 | 0.001 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.002 | 0.001 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.003 | 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".