fce14f038e
First transmission through a real radio path in the project. A 4756-byte JPEG went from transmitter to receiver over two antennas 60 cm apart at 225 MHz and reassembled byte-identical, reproduced across three runs. The cable loopback still needs an SMA male-to-male adapter that has not arrived, so this air run is a track verification, not the controlled measurement: room levels are not held the way a cable holds them. Its purpose was to exercise the device wrapper the models cannot cover. Four defects the software model passed but the hardware exposed, each reproduced and fixed: - a 566 528-sample frame did not fit the 262 144 receive buffer, and the sample stream is not continuous across separate reads, so a frame on the seam was destroyed. Reception now uses one buffer sized to the frame - carrier correction was always applied, but with a shared reference the true offset is near zero and the 80-symbol marker estimate is noise; correcting by it rotated phase along the whole frame, 65% bit errors measured. Ported should_apply_cfo_correction from Lab023 - receiver gain of 20 dB left the signal at 0.0003 of full scale. Levels set by measurement: RX 50 dB, TX -10 dB give zero bit errors with margin - the error-vector metric returned zero on a failed receive, reporting a perfect signal where there was none, the same class of defect as the written-in figures of Lab041. Replaced with an explicit not-computed value The air TX gain ceiling is now derived from the link budget by antenna distance rather than a constant. Three loopback modes: software, cable, air. PROJECT_LOG entry 019 records the run and the defects. Software and cable results stay reproducible; 125 tests pass, gate passes.
1.4 KiB
1.4 KiB
| 1 | index | packet_bytes | frame_bits | correlation_score | sample_phase | carrier_offset_hz | carrier_coherence | cfo_correction_applied | error_vector_magnitude | frame_found | header_parsed | crc_valid | fragment_recovered |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2 | 0 | 536 | 4384 | 0.9995083676316812 | 15 | -0.8161804653898344 | 0.9999521460387033 | False | 0.013939054015288657 | True | True | True | True |
| 3 | 1 | 536 | 4384 | 0.9994247234007716 | 49 | 0.034058565997241885 | 0.9999449532988285 | False | 0.007533311365459869 | True | True | True | True |
| 4 | 2 | 536 | 4384 | 0.9995067920215722 | 121 | -0.4024654150100275 | 0.9999698768639075 | False | 0.007802389734928202 | True | True | True | True |
| 5 | 3 | 536 | 4384 | 0.9995973624847003 | 79 | 0.05360429263743072 | 0.9999563681724133 | False | 0.008067411996806204 | True | True | True | True |
| 6 | 4 | 536 | 4384 | 0.9995573203179389 | 37 | -0.7726047795897841 | 0.999951969069221 | False | 0.008830283803028178 | True | True | True | True |
| 7 | 5 | 536 | 4384 | 0.9994972026358666 | 35 | 0.14518673176235097 | 0.9999740428064059 | False | 0.007829934600060385 | True | True | True | True |
| 8 | 6 | 536 | 4384 | 0.9994993201100448 | 33 | -0.6575975246787777 | 0.9999581020309138 | False | 0.008192298206454165 | True | True | True | True |
| 9 | 7 | 536 | 4384 | 0.9995337736352732 | 97 | -0.32146831121434616 | 0.9999654759558527 | False | 0.00773812855638587 | True | True | True | True |
| 10 | 8 | 536 | 4384 | 0.9995377136427829 | 90 | -0.32692415971800415 | 0.9999706666958124 | False | 0.008197030505111991 | True | True | True | True |
| 11 | 9 | 172 | 1472 | 0.9994478378475372 | 53 | -0.6175162038574342 | 0.9999730687021144 | False | 0.011683449034017782 | True | True | True | True |