MeshCore/sim/CHANGELOG.md

Simulation Harness Changelog

[Unreleased] — Adaptive Routing + TX Power Saving

Added

Core Infrastructure

• SimRadio.h: Added tx_power_dbm field (public, default 20 dBm). Extended TxCallback signature to carry tx_power_dbm through to the bus. Existing capture-effect collision model (6 dB threshold) unchanged.
• SimBus.h: InFlightPacket now carries tx_power_dbm. deliverPending() applies received_snr += (tx_power_dbm - 20.0) at each receiver — lower TX power shrinks effective SNR without touching the channel model. Added _tsnode_to_seq compound-key map (src_pub_key[0..3] << 32 | advert_ts) for concurrent-flood tracking; prevents false metric attribution when two senders fire in the same simulated second.
• DensityEstimator.h (new): Passive sliding-window neighbour density estimator. Counts unique direct senders (hop_count==1) over a 60 s window. Returns SPARSE / MEDIUM / DENSE tier. No protocol messages required. Uses std::unordered_set<uint32_t> (no fixed cap).
• RoutingStrategies.h: Added ADAPTIVE to the RoutingStrategy enum. Added adaptiveRelayPct(), adaptiveDelay(), hashBasedRelay() helpers alongside existing snrWeightedDelay() and pathSnrHybridDelay().
• SimNode.h: Added routing_strategy field (default DEFAULT). Added DensityEstimator density member fed from logRx(). Added power-save fields (power_save_enabled, power_save_dense_dbm, power_save_medium_dbm, full_power_dbm). Added battery energy tracking (total_tx_energy_mah, total_rx_energy_mah, total_rx_time_ms, total_suppressed). Added static float txCurrentMa(float dbm) and constants RX_CURRENT_MA, IDLE_CURRENT_MA matching SX1262 datasheet.
• scenario_adaptive.cpp: Validates ADAPTIVE vs DEFAULT vs PATH_SNR_HYBRID across FullMesh 50, Chain 20, Grid 5×5 at multiple SNR levels. Confirms ADAPTIVE reduces airtime ≈ 65% at equivalent delivery rate.
• scenario_concurrent.cpp: Tests 2–8 simultaneous flood sources. Confirms ADAPTIVE maintains delivery advantage in grid topologies under concurrent load; documents known limitation in adversarial full-mesh simultaneous-TX edge case.
• scenario_longchain.cpp: Tests 20-hop linear chains at marginal SNR. Confirms ADAPTIVE stays at SPARSE tier throughout and behaves identically to DEFAULT on chains.
• scenario_mixed.cpp: Tests ADAPTIVE nodes coexisting with DEFAULT (legacy) nodes. Confirms full interoperability with no delivery regression.
• scenario_dutycycle.cpp: Tests EU 1% duty cycle enforcement (getAirtimeBudgetFactor()). Confirms ADAPTIVE requires ≈ 40% fewer TX budget slots than DEFAULT.
• scenario_relay_pct_sweep.cpp: Grid sweep of DENSE% × MEDIUM% relay percentages across FM50, FM100, Chain20, Grid5×5. Identifies optimal operating point (DENSE=15%, MEDIUM=25%). Outputs CSV + ranked table.
• scenario_txpower.cpp (new): Tests adaptive TX power reduction at CONSERV / MODERATE / AGGRESSIVE levels across FM50, DC6x6 dense positional cluster, and CH20 chain. Measures delivery rate, latency, and per-node energy consumption. Includes 48-hour festival weekend battery projection.
• ADAPTIVE_ROUTING.md (new): Full design rationale, configuration reference, and empirical results.

Fixed

• DensityEstimator: Replaced fixed seen[64] array with std::unordered_set<uint32_t> — eliminated silent 64-neighbour cap that could misclassify dense networks as MEDIUM.
• SimBus::onTransmit: Added if (len > 255) len = 255 bounds guard before memcpy into 255-byte InFlightPacket buffer.
• SimNode::getRetransmitDelay: Fixed redundant TX power reset condition (!power_save_enabled || strategy != ADAPTIVE → strategy != ADAPTIVE).
• SimNode::getRetransmitDelay: Fixed p_forward gate floating-point edge: >= → > so p_forward=1.0 never silently drops a relay.
• scenario_concurrent.cpp: Fixed stale pointer ConcurrentResult* def_base = &group.back() (invalidated by subsequent push_back) — replaced with value copy + bool have_def flag.
• scenario_relay_pct_sweep.cpp: Updated addSweepNode TxCallback from 4-arg to 5-arg to match updated SimRadio signature. Updated on_recv lambda to use _tsnode_to_seq compound key instead of old _ts_to_seq.
• scenario_adaptive.cpp: Removed unused variable last_suppressed.

Changed

• SimBus protected members promoted from private: to protected: to allow SweepBus subclass access in scenario_relay_pct_sweep.cpp.
• adaptiveRelayPct(): DENSE raised 10% → 15%, MEDIUM raised 20% → 25% — improves resilience under concurrent multi-source floods without increasing airtime in the single-source case.