Performance of an infrared wireless CDMA system
Why this work is in the frame
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Bibliographic record
Abstract
Infrared (IR) is a new medium for wideband wireless applications especially at indoors. Infrared has abundant bandwidth and does not require FCC approval enabling rapid deployment. Intensity modulated systems do not experience multipath fading. However, health regulations limit the laser output power [IEC 825]. Photodetectors with large photosensitive areas have high sensitivity but they also have high junction capacitance that limits the bandwidth. High ambient noise is another concern in infrared systems. Spreading the spectrum, which enables low power transmission, can be used to overcome these limitations. In this paper, we evaluate the performance of a direct spread CDMA type infrared wireless system in a multiuser environment considering: multi-user interference and inter-symbol-interference assuming different channel models. According to the simulation a BER of 10-7 can be achieved with a moderate bit rate when, the channel impulse response exponentially decays. The maximum bit rate, however, depends on the mean square value of the channel dispersion. Lab prototype agrees with the theory and shows ambient light is the biggest concern in a pico cellular environment with few users.
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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) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.001 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 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 it