RTK Tuning Gates

The default RTK pipeline is the sign-off path for the PPC production runs. Additional gates are default-off unless noted here and are intended for diagnostics, profile sweeps, or dataset-specific opt-in profiles such as Odaiba.

Default Guards

The low-speed non-FIX drift guard is part of the default kinematic output path, including the coverage profile. It rejects long FLOAT/SPP fallback drifts only when the surrounding FIX anchors indicate near-stationary motion. Use --no-nonfix-drift-guard to reproduce the raw unguarded fallback stream.

The SPP height-step guard is also default-on in the kinematic output path. It rejects SPP-only vertical spikes above --spp-height-step-min / --spp-height-step-rate while preserving FLOAT and FIXED epochs.

The FLOAT bridge-tail guard is default-on after six-run PPC sign-off. It rejects FLOAT epochs in slow bounded FIX-to-FIX segments when they diverge from the anchor bridge, and uses horizontal FIX-anchor speed for its motion gate. Use --no-float-bridge-tail-guard to reproduce the pre-bridge-tail coverage stream.

Opt-In Gates

Flag	Purpose	Default
--ar-policy {extended\|demo5-continuous}	AR extras gate. demo5-continuous disables relaxed-hold-ratio / subset-fallback / hold-fix / Q-regularization for demo5-style continuous ambiguity tracking.	extended
--max-subset-ar-drop-steps <N>	Extend the progressive subset-AR search by dropping up to N worst-variance DD pairs. Diagnostic only: Nagoya run2 spot checks showed extra candidates are usually rejected by the jump gate unless paired with riskier validation changes.	6
--max-hold-div <m>	Reject fix if the hold-state diverges from float by more than N meters.	0 disabled
--max-pos-jump <m>	Reject fix if the epoch-to-epoch position jump exceeds N meters. Truth-validation against PPC reference showed jumps cluster at <5 m for correct fixes or >10 m for wrong FIX. Pass 0 to disable.	5 m
--max-pos-jump-min <m> + --max-pos-jump-rate <m/s>	Reject fix if the jump from the last fixed position exceeds max(min, rate * dt), so vehicle gaps can be tested without a stale absolute distance clamp.	0 / 0 disabled
--max-float-spp-div <m>	Reject FLOAT epochs that diverge from the same-epoch SPP solution by more than N meters, then fall back to SPP/no-solution. Diagnostic gate for PPC FLOAT high-error sweeps.	0 disabled
--max-float-prefit-rms <m> + --max-float-prefit-max <m> + --max-float-prefit-reset-streak <N>	Reset ambiguity states for the next epoch after N consecutive otherwise accepted FLOAT epochs have high DD prefit residual RMS or max residual. The current FLOAT epoch is still reported.	0 / 0 disabled / 3
--min-float-prefit-trusted-jump <m>	Continuity selector for the residual gate. When > 0, high-residual FLOAT resets are allowed only if the FLOAT position has also diverged by at least N meters from the last trusted FIX/FLOAT position.	0 disabled
--max-update-nis-per-obs <v>	Reject a whole RTK DD Kalman update before state/covariance mutation when normalized innovation squared divided by active observations exceeds N.	0 disabled
--max-fixed-update-nis-per-obs <v>	Reject only FIXED ambiguity candidates when the preceding RTK DD update NIS divided by active observations exceeds N, while retaining the FLOAT solution for that epoch.	0 disabled
--max-fixed-update-post-rms <m>	Reject only FIXED ambiguity candidates when the preceding RTK DD update post-suppression residual RMS exceeds N meters, while retaining the FLOAT solution for that epoch.	0 disabled
--max-fixed-update-gate-ratio <v>	Apply the fixed-only NIS/post-RMS gates only when the AR ratio is finite and at or below N.	0 unconditional when gates are enabled
--min-fixed-update-gate-baseline <m> + --max-fixed-update-gate-baseline <m>	Optional baseline-length window for the fixed-only NIS/post-RMS gates.	0 / 0 disabled
--min-fixed-update-gate-speed <m/s> + --max-fixed-update-gate-speed <m/s>	Optional speed window for the fixed-only NIS/post-RMS gates.	0 / 0 disabled
--max-fixed-update-secondary-gate-ratio <v> + baseline/speed secondary window flags	Optional second OR-window for fixed-only NIS/post-RMS gates.	0 for all fields
--demote-fixed-status-max-ratio <v>	Keep the position solution but output FIX as FLOAT when the AR ratio is finite and at or below N. PPC nis2-ratio4 uses this to reduce measured Wrong/FIX while preserving official-score coverage.	0 disabled
--rtk-snr-weighting + --rtk-snr-reference-dbhz <v> + --rtk-snr-max-variance-scale <v> + --rtk-snr-min-baseline <m>	Low-cost observation model diagnostic. Uses the lower rover/base SNR for each SD link and inflates DD phase/code variance below the reference SNR, capped by the max scale.	false / 45 / 25 / 0
--cycle-slip-threshold <m> + --doppler-slip-threshold <m> + --code-slip-threshold <m> + --strict-dynamic-slip-thresholds + --adaptive-dynamic-slip-thresholds	Cycle-slip sensitivity sweep. Dynamic RTK keeps protective minimum thresholds by default; strict/adaptive modes are opt-in urban reacquisition experiments.	0.05 / 0.20 / 5.0 / false / false
--adaptive-dynamic-slip-nonfix-count <N>	Non-FIX epochs before adaptive dynamic slip thresholds activate.	3
--adaptive-dynamic-slip-hold-epochs <N>	Epochs to keep adaptive dynamic slip thresholds after activation.	10
--nonfix-drift-max-residual <m> + --nonfix-drift-min-horizontal-residual <m>	Tighten the default low-speed non-FIX drift guard for tail diagnostics while avoiding vertical-only fallback pruning.	30 / 0
--fixed-bridge-burst-guard + --fixed-bridge-burst-max-residual <m>	Reject isolated short FIX bursts when they diverge from the straight bridge between surrounding FIX anchors.	false / 20
--max-consec-float-reset <N>	Auto-reset ambiguities after N consecutive float epochs. 10 is a historical PPC official-score probe; the current PPC sign-off path is --realtime-profile sigma-demote.	0 disabled
--max-consec-nonfix-reset <N>	Auto-reset ambiguities after N consecutive FLOAT/SPP/no-solution epochs.	0 disabled
--max-postfix-rms <m>	Reject fix if the L1 post-fix DD phase residual RMS exceeds N meters.	0 disabled
--enable-wide-lane-ar + --wide-lane-threshold <cycle>	Pre-compute MW wide-lane integers and inject them as Kalman constraints into the LAMBDA search. Odaiba's opt-in preset uses this to beat demo5 Hmed while still beating demo5 Fix count and tails.	false / 0.25
--enable-wlnl-fallback	Allow the experimental MW wide-lane / narrow-lane fallback after ordinary LAMBDA failure in non-IFLC runs. It reuses --wide-lane-threshold for both integer checks.	false
--enable-bsr-decimation + --bsr-worst-axes <N> + --bsr-max-drops <N>	Add BSR-guided subset AR decimation candidates alongside the variance-drop subset family. PPC high-wrong probes preserved FIX count but did not reduce Wrong/FIX, so this remains diagnostic.	false / 3 / 6

On PPC Tokyo and Nagoya, leave these off unless reproducing a specific sweep. On Odaiba or other urban multipath datasets, use --preset odaiba for the explicit demo5-beating tradeoff.