Modulated continuous TX + active link-probe (adaptive-link building blocks)#178
Merged
Conversation
…locks)
Add the transmit-side active stimulus the sensing toolkit was missing, and an
active link-probe that composes it with the RX sensors into an operating-point
recommendation — building blocks for the energy-minimizing adaptive link.
Modulated continuous TX (DEVOURER_CONT_TX): a true 100%-duty full-channel
modulated OFDM carrier — the modulated sibling of the CW tone — on all three
chip generations via Realtek's MP hardware continuous-TX mode:
- Jaguar1: the 0x914 continuous-TX register (mpt_StartOfdmContTx).
- Jaguar2: the same register once rCCAonSec (0x838)=0x6d is set first;
without it the 0x914 bit wedges the USB TX FIFO.
- Jaguar3: the JGR3 PMAC packet generator — stop the normal TRX (pause the
TX queues, disable OFDM/CCK CCA), define a legacy-6M PMAC packet, then
enable PMAC + the 0x1ca4 continuous hold.
Each idle-holds the carrier until SIGINT, then restores the chip cleanly.
Exposed per-chip (StartContinuousTx/StopContinuousTx), reached by downcast from
the demo like the CW tone; SDR-verified as a flat ~18 MHz OFDM block via the new
tests/sdr_spectrum.py (occupied-bandwidth / peakiness discriminates a modulated
block from a bare tone).
Active link-probe (tests/link_probe.sh + tests/link_probe.py): one adapter emits
a modulated feed and sweeps its TX power in steps; the ground station reads its
per-step SNR and NHM; the analyzer aligns the two by wall-clock and reports the
margin-vs-power curve plus the minimum power that clears a target SNR — the
energy-min reflex made measurable. The same harness serves the MCS-headroom axis.
Docs: docs/adaptive-link-building-blocks.md catalogs the levers, sensors, active
stimuli, and probes an adaptive controller composes, and maps them onto the
energy-min design (docs/adaptive-link.md); the README entry is condensed to a
pointer.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
josephnef
added a commit
that referenced
this pull request
Jul 5, 2026
Completes the active link-probe and adds the remaining adaptive-link building-block harnesses — follow-up to #178. ## MCS-headroom axis `DEVOURER_TX_MCS_SWEEP="MCS0,MCS2,…"` steps the on-air rate through a list (a beacon-feed rate sweep, decoupled from the idle-hold continuous carrier like the power ramp), marking each step with `<devourer-contx>mcs=`. `link_probe.py` auto-detects the swept axis, aggregates per rate across sweep cycles, and for the MCS axis recommends the **highest rate whose ground SNR clears the target** — the "ride the fastest modulation the link holds" reflex. `link_probe.sh` gains `--axis power|mcs`. (The prior version claimed the harness served the MCS case but only implemented the power axis — this makes it real.) ## Thermal-budget overlay The probe polls the emitter's PA thermal meter during the sweep and reports the drift, bounding the sustainable power/duty — the drone's local safety input. ## Rendezvous beacon `tests/rendezvous.sh`: the ground parks a modulated continuous beacon on a channel; the drone scans candidate channels with its frame-free energy sensor and locks onto the beacon's channel — the asymmetric-duty rendezvous composed from the continuous-TX stimulus and the RX energy sensor. ## Docs Note that the continuous carrier is a spectral/thermal stimulus, **not** a clean frame source (its looped payload isn't FCS-valid), which is why the probe uses a beacon feed for decodable per-frame SNR; and flag the 100%-duty PA heat as a debug/characterisation caveat. ## Testing - Build clean; `ctest` green (4/4). - Hardware-validated (two adapters, no SDR): - MCS axis: per-rate SNR curve + correct "highest rate that holds the floor" recommendation. - Power axis: unchanged (monotonic curve + "cheapest power" recommendation). - Rendezvous: the scanner locked onto the beacon's channel (energy ~27× floor). - Decodability characterised: the Jaguar1 continuous carrier is PHY-decodable (per-frame SNR available); the Jaguar3 PMAC carrier is a spectral stimulus, not a frame stream — hence the probe's beacon feed. 🤖 Generated with [Claude Code](https://claude.com/claude-code) --------- Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
The transmit-side counterpart to the RX sensing toolkit: a realistic active
stimulus, plus an active probe that composes it with the RX sensors into an
operating-point recommendation — building blocks for the energy-minimizing
adaptive link.
DEVOURER_CONT_TX— modulated continuous TXThe modulated sibling of
DEVOURER_CW_TONE: instead of a bare carrier, a true100%-duty full-channel modulated OFDM carrier at a real rate, on all three
chip generations via Realtek's MP hardware continuous-TX mode. SDR-verified as a
flat ~18 MHz OFDM block (
tests/sdr_spectrum.pydiscriminates a modulated blockfrom a tone by occupied bandwidth), on every generation:
0x914continuous-TX register (mpt_StartOfdmContTx).rCCAonSec(0x838)=0x6dis setfirst; without it the
0x914bit wedges the USB TX FIFO.TX queues, disable OFDM/CCK CCA), define a legacy-6M PMAC packet, then enable
PMAC + the
0x1ca4continuous hold.Each idle-holds the carrier until SIGINT, then restores the chip cleanly
(verified: an immediate re-run reproduces the carrier with no replug). Exposed
per-chip (
StartContinuousTx/StopContinuousTx), reached by downcast from thedemo exactly like the CW tone.
Active link-probe
tests/link_probe.sh+tests/link_probe.py: one adapter emits a modulatedfeed and sweeps its TX power in steps; the ground station reads its per-step SNR
and NHM; the analyzer aligns the two by wall-clock and reports the
margin-vs-power curve plus the minimum power that clears a target SNR — the
energy-min reflex made measurable (ride the least power that holds the link). The
same harness serves the MCS-headroom axis. Two adapters, no SDR.
Docs
docs/adaptive-link-building-blocks.md(new) catalogs the levers, sensors,active stimuli, and probes an adaptive controller composes, and maps them onto
the energy-min design. The README entry is condensed to a pointer (kept light).
Testing
ctestgreen (4/4).(Jaguar1 8812AU, Jaguar2 8822BU, Jaguar3 8822CU), distinct from the CW
tone's spike and from a beacon flood; clean chip restore on stop.
the correct "minimum power that clears the target" recommendation.
🤖 Generated with Claude Code