RF Class-D Amplification With Bandpass Sigma–Delta Modulator Drive Signals
Bibliographic record
Abstract
The power efficiency of a RF Class-D amplifier with a bandpass sigma-delta (SigmaDeltaM) modulator is analyzed for a complementary voltage-switched configuration. The modulator broadens the application of the amplifier to include signals with time varying envelopes such as W-CDMA. The addition of a modulator introduces new design variables which affect amplifier power efficiency including coding efficiency and the average transition frequency of the pulse train. Design equations are derived for the optimum load impedance, output power, conduction losses, capacitive switching losses, and drain efficiency. The general design equations are consistent with both periodic and aperiodic drive signals. Analytic and simulated results are compared for an example design with pseudomorphic high-electron mobility transistor and metal-semiconductor field-effect transistor switches with a fourth-order bandpass SigmaDeltaM. The results show a drain efficiency of 52% with a 10-dB peak-to-average power ratio W-CDMA source signal at a frequency of 500 MHz
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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 | 0.000 |
| 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) | 0.001 | 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 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".