Differential receiver design for the Offset-QPSK modulation scheme: ISI-free and non-ISI-free receiver algorithms
Bibliographic record
Abstract
Modulation formats for mobile communications need to support non-linear amplifiers and allow for fast acquisition. A communication system using Offset-QPSK (OQPSK) and differential demodulation satisfies these requirements. Thus, in this thesis, we present two classes of differential receivers for OQPSK. The first class of receivers deals with ISI-free transmission and are attractive solutions because of their simple design. However, the ISI-free transmission assumption strictly requires a pulse shape with maximum excess bandwidth. The second class of receivers are able to deal with ISI by using trellis decoding and the Viterbi algorithm and are, thus, more computationally complex. In this case, efficient use of the bandwidth can be achieved, by optimizing the pulse shapes used, while maintaining the decoder's good performance. The pulse shapes derived include the Modified Raised Cosine (MRC), the Truncated Raised Cosine (TRC) and the Raised Cosine 2 (RC2).
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 | 0.001 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.000 | 0.001 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.001 | 0.001 |
| 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; both teacher heads agree on what is shown here.
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".