System Architecture

Mini v1 Decision Flow Diagram

flowchart TD
    Start([TinySA Sweep]) --> Baseline[Compare to Baseline]
    Baseline --> Anomaly{Anomaly Detected?}
    Anomaly -->|No| Clear[CLEAR]
    Anomaly -->|Yes| JammerCheck[Jammer Heuristic]

    JammerCheck --> WidebandCheck{>30% bins elevated?}
    WidebandCheck -->|Yes| WidebandFlat{Peak-avg < 6 dB?}
    WidebandFlat -->|Yes| Wideband[WIDEBAND_JAMMING]
    WidebandFlat -->|No| ContinueWB[Continue to band match]
    WidebandCheck -->|No| SpotCheck{>30 dB peak in narrow region?}
    SpotCheck -->|Yes| Spot[SPOT_JAMMING]
    SpotCheck -->|No| ContinueSP[Continue to band match]

    ContinueWB --> BandMatch[Match Frequency to Generic Bands]
    ContinueSP --> BandMatch

    BandMatch --> GPS{1.57 GHz?}
    GPS -->|Yes| GPSJam[GPS_THREAT]
    GPS -->|No| UHF433{410-480 MHz?}
    UHF433 -->|Yes| D433[DRONE_433]
    UHF433 -->|No| ISM900{860-1020 MHz?}
    ISM900 -->|Yes| MilitaryCheck{Power > -50 dBm?}
    MilitaryCheck -->|Yes| MilUHF[MILITARY_UHF]
    MilitaryCheck -->|No| D900[DRONE_900]
    ISM900 -->|No| ISM24{2.4-2.5 GHz?}
    ISM24 -->|Yes| D24[DRONE_2G4]
    ISM24 -->|No| Cband{4.4-5.85 GHz?}
    Cband -->|Yes| NATO[NATO_CBAND]
    Cband -->|No| ISM58{5.7-5.9 GHz?}
    ISM58 -->|Yes| D58[DRONE_5G8]
    ISM58 -->|No| Unknown[UNKNOWN]

    style Wideband fill:#f66,stroke:#333,stroke-width:2px
    style Spot fill:#f66,stroke:#333,stroke-width:2px
    style GPSJam fill:#f66,stroke:#333,stroke-width:2px
    style MilUHF fill:#f96,stroke:#333,stroke-width:2px
    style Clear fill:#9f9,stroke:#333,stroke-width:2px
                    

Mini v2 Full I/Q Flow

flowchart TD
    Start([HAMGEEK I/Q Capture]) --> Sweep[Stage 1 Spectrum Sweep]
    Sweep --> Candidates{Candidate frequencies found?}
    Candidates -->|No| Clear[CLEAR]
    Candidates -->|Yes| IQCapture[Stage 2 I/Q Capture]

    IQCapture --> Features[IQAnalyzer 35 Features]
    Features --> SNRGate{SNR >= 10 dB?}
    SNRGate -->|No| LowSNR[Cap confidence 0.35]
    SNRGate -->|Yes| NoiseGate[NoiseGateClassifier]

    NoiseGate --> NoiseCheck{Noise?}
    NoiseCheck -->|Yes| Reject[Reject as Noise]
    NoiseCheck -->|No| RFGate[RFGateClassifier]

    RFGate --> RFClass{RF Class?}
    RFClass -->|wifi/bt/lora/bg| SafetyCheck{FHSS_OFDM or wideband?}
    SafetyCheck -->|Yes| Override[Override Never Suppress]
    SafetyCheck -->|No| Benign[Suppress as Benign]
    RFClass -->|drone| BenignReject[BenignRejector]
    Override --> BenignReject

    BenignReject --> Spectrogram[iq_to_spectrogram 256x256]
    Spectrogram --> CNN[ONNX ResNet-18 on CPU]
    CNN --> Hybrid[HybridDecisionEngine]
    Hybrid --> Result[Specific Drone Type + Confidence]
    LowSNR --> Result

    style Reject fill:#666,stroke:#333,stroke-width:2px,color:#fff
    style Benign fill:#666,stroke:#333,stroke-width:2px,color:#fff
    style Result fill:#9f9,stroke:#333,stroke-width:2px
    style Clear fill:#9f9,stroke:#333,stroke-width:2px
                    

Pro Tier Decision Flow Diagram

flowchart TD
    Start([PlutoSDR I/Q]) --> FFT[FFT - Power Spectrum]
    FFT --> Features[Extract 35 Features]

    Features --> Basic[Basic: freq, BW, power, SNR]
    Features --> Spectral[Spectral: flatness, entropy, PAPR]
    Features --> STFT[STFT - Hopping Analysis]
    Features --> Cyclo[Cyclostationary Analysis]

    Cyclo --> CycloGate{noise_conf > 0.8?}
    CycloGate -->|Yes| Noise[Reject as NOISE]
    CycloGate -->|No| CycloOFDM{OFDM CP detected?}
    CycloOFDM -->|Yes| OFDMCP[OFDM/FHSS_OFDM confidence 0.85]
    CycloOFDM -->|No| Heuristic[Heuristic Tree]

    STFT --> HopDensity{Hop density > 30%?}
    HopDensity -->|Yes| NoiseHop[Reject hopping - Random noise]
    HopDensity -->|No| HopValid[Valid FHSS]

    Spectral --> PAPR{PAPR > 8 dB?}
    PAPR -->|Yes| Hopping{Hopping detected?}
    Hopping -->|Yes| FHSSOFDM[FHSS_OFDM]
    Hopping -->|No| BWCheck{BW > 5 MHz?}
    BWCheck -->|Yes| OFDM[OFDM]
    BWCheck -->|No| Continue[Continue heuristic]
    PAPR -->|No| Flatness{Flatness < 0.3?}
    Flatness -->|Yes| FSK[FSK/DSSS]
    Flatness -->|No| Continue

    OFDMCP --> Scoring[Multi-Factor Scoring]
    FHSSOFDM --> Scoring
    OFDM --> Scoring
    FSK --> Scoring
    Continue --> Scoring
    Heuristic --> Scoring
    HopValid --> Scoring

    Scoring --> Result[Best Match + Confidence]

    style Noise fill:#666,stroke:#333,stroke-width:2px,color:#fff
    style NoiseHop fill:#666,stroke:#333,stroke-width:2px,color:#fff
    style Result fill:#9f9,stroke:#333,stroke-width:2px
                    

900 MHz Disambiguation Decision Tree

flowchart TD
    Start[900 MHz Signal Detected] --> IQ{I/Q Available?}

    IQ -->|No - Mini Tier| Power{Power Level}
    Power -->|> -50 dBm| MilUHF[MILITARY_UHF]
    Power -->|< -50 dBm| D900[DRONE_900]

    IQ -->|Yes - Pro Tier| Modulation[Analyze Modulation]
    Modulation --> LoRa{LoRa CSS?}
    LoRa -->|Yes| DualBand{Dual-band 868+902 MHz?}
    DualBand -->|Yes| Lancet[LANCET confidence 0.85]
    DualBand -->|No| HopRate{Hop rate?}
    HopRate -->|25-500 Hz| ELRS[ELRS confidence 0.75]
    HopRate -->|~50 Hz| Crossfire[CROSSFIRE confidence 0.75]

    LoRa -->|No| FHSS{FHSS detected?}
    FHSS -->|Yes| SlowHop{Slow hopping 1-2 Hz?}
    SlowHop -->|Yes| Channels{8-16 channels?}
    Channels -->|Yes| Orlan[ORLAN-10 confidence 0.70]
    Channels -->|No| Supercam[SUPERCAM confidence 0.65]
    SlowHop -->|No| FastHop{40-60 Hz?}
    FastHop -->|Yes| LancetFHSS[LANCET confidence 0.75]
    FastHop -->|No| Generic[MILITARY_UHF confidence 0.50]

    FHSS -->|No| FSK{FSK/DSSS?}
    FSK -->|Yes| BW{Bandwidth?}
    BW -->|200-400 kHz| OrlanFSK[ORLAN-10 confidence 0.60]
    BW -->|5 MHz| SupercamWide[SUPERCAM confidence 0.60]

    style Lancet fill:#f66,stroke:#333,stroke-width:3px
    style Orlan fill:#f96,stroke:#333,stroke-width:3px
    style Supercam fill:#fc6,stroke:#333,stroke-width:3px
    style ELRS fill:#9cf,stroke:#333,stroke-width:2px
    style Crossfire fill:#9cf,stroke:#333,stroke-width:2px
                    

Multi-Band Correlation Flow

flowchart TD
    Start[Detection on Band A] --> Store[Store in Correlation Window ±2 seconds]
    Store --> Check{Other bands detected in window?}

    Check -->|No| SingleBand[Single-Band Detection confidence as-is]
    Check -->|Yes| Pattern[Match Multi-Band Pattern]

    Pattern --> DJI{2.4 GHz + 5.8 GHz?}
    DJI -->|Yes| DJIConf[DJI Confirmed +0.15 confidence boost]

    Pattern --> Orlan{900 MHz + 1.1 GHz or 2.4 GHz?}
    Orlan -->|Yes| OrlanConf[ORLAN-10 Confirmed +0.20 confidence boost]

    Pattern --> Lancet{900 MHz dual + 2.4 GHz?}
    Lancet -->|Yes| LancetConf[LANCET Confirmed +0.25 confidence boost]

    Pattern --> Bayraktar{4.4-5.85 GHz + Ku?}
    Bayraktar -->|Yes| BayraktarConf[BAYRAKTAR Confirmed +0.20 confidence boost]

    DJIConf --> FusedEvent[Fused Multi-Band Event]
    OrlanConf --> FusedEvent
    LancetConf --> FusedEvent
    BayraktarConf --> FusedEvent
    SingleBand --> Output[Output Event]
    FusedEvent --> Output

    style FusedEvent fill:#9f9,stroke:#333,stroke-width:3px
    style LancetConf fill:#f66,stroke:#333,stroke-width:2px
    style OrlanConf fill:#f96,stroke:#333,stroke-width:2px
                    

FHSS Analysis Pipeline

flowchart TD
    Start([I/Q Samples]) --> STFT[Short-Time Fourier Transform 256-sample window 64-sample hop]
    STFT --> Spectrogram[Time-Frequency Spectrogram]
    Spectrogram --> PeakTrack[Track Peak Frequency Over Time]

    PeakTrack --> Transitions{Count Frequency Transitions}
    Transitions --> Hops{Count Total Hops}

    Hops --> Density[Hop Density = num_hops / num_transitions]
    Density --> DensityGate{Density > 30%?}

    DensityGate -->|Yes| Noise[Reject as Noise - Random peak jumping]
    DensityGate -->|No| ValidFHSS[Valid FHSS Signal]

    ValidFHSS --> HopRate[Hop Rate = num_hops / duration]
    ValidFHSS --> Dwell[Dwell Time = time between hops]
    ValidFHSS --> HopBW[Hop Bandwidth = max_freq - min_freq]
    ValidFHSS --> Channels[Hop Frequencies = list of distinct peaks]

    HopRate --> CV[Coefficient of Variation of Dwell Times]
    CV --> Regularity{CV < 0.3?}
    Regularity -->|Yes| Structured[Structured FHSS - High confidence]
    Regularity -->|No| Irregular[Irregular Hopping - Lower confidence]

    Structured --> Output[Hop Analysis Result]
    Irregular --> Output

    style Noise fill:#666,stroke:#333,stroke-width:2px,color:#fff
    style Structured fill:#9f9,stroke:#333,stroke-width:2px
    style Irregular fill:#fc6,stroke:#333,stroke-width:2px
                    

Cyclostationary Analysis Flow

flowchart TD
    Start([I/Q Samples]) --> LengthCheck{Length >= 8192?}
    LengthCheck -->|No| Skip[Skip Cyclo - Use Heuristics]
    LengthCheck -->|Yes| AlphaProfile[Compute Alpha Profile FFT of x squared]

    AlphaProfile --> AlphaPeaks[Detect Alpha Peaks 20-10000 Hz]
    AlphaPeaks --> FHSSDetect{Strong alpha peaks in hop range?}
    FHSSDetect -->|Yes| HopRateExt[Extract FHSS Hop Rate from peak location]
    FHSSDetect -->|No| NoHop[No FHSS detected]

    Start --> Envelope[Compute Envelope]
    Envelope --> EnvVar[Envelope Variance]
    EnvVar --> ConstEnv{Variance < 0.1?}
    ConstEnv -->|Yes| ConstSig[Constant-Envelope Signal - Definitively NOT noise]
    ConstEnv -->|No| VarEnv[Variable Envelope]

    VarEnv --> AlphaStr[Alpha Peak Strength]
    AlphaStr --> NoiseConf{Alpha strength > 0.5?}
    NoiseConf -->|No| HighNoiseConf[noise_confidence > 0.8 REJECT as noise]
    NoiseConf -->|Yes| LowNoiseConf[noise_confidence < 0.8 Likely signal]

    Start --> Autocorr[Autocorrelation]
    Autocorr --> CPSearch[Search for CP Peak lag = 1024-4096]
    CPSearch --> CPDetect{CP peak > 0.7?}
    CPDetect -->|Yes| SymRate[Symbol Rate from CP peak location]
    CPDetect -->|No| NoCP[No OFDM CP]

    SymRate --> CPRatio[CP Ratio = CP_length / symbol_length]
    CPRatio --> OFDMConf[OFDM Confirmed confidence 0.85]

    OFDMConf --> Features[Cyclostationary Feature Output]
    HopRateExt --> Features
    HighNoiseConf --> Features
    LowNoiseConf --> Features
    ConstSig --> Features
    NoCP --> Features
    NoHop --> Features
    Skip --> NullFeatures[All cyclo fields: None]

    style HighNoiseConf fill:#666,stroke:#333,stroke-width:2px,color:#fff
    style OFDMConf fill:#9f9,stroke:#333,stroke-width:2px
    style ConstSig fill:#9cf,stroke:#333,stroke-width:2px
                    

DJI Model Identification Flow

flowchart TD
    Start[DJI Detected on 2.4 GHz] --> IQ{I/Q Available?}
    IQ -->|No| Generic[DJI Generic]

    IQ -->|Yes| Mod[Modulation Type]
    Mod --> FHSSOFDM{FHSS_OFDM?}
    FHSSOFDM -->|Yes| SymRate{Symbol Rate 1.4-1.7 MHz?}
    SymRate -->|Yes| OcuSync[OcuSync Platform]
    SymRate -->|No| OtherMod[Other OFDM]

    FHSSOFDM -->|No| WiFiCheck{Plain OFDM No hopping?}
    WiFiCheck -->|Yes| Mini[DJI Mini WiFi-based]

    OcuSync --> BW[Measure 6 dB Bandwidth]
    BW --> BWRange{Bandwidth Range?}

    BWRange -->|0.5-1.0 MHz| Air[DJI Air 2S Narrowband]
    BWRange -->|2.0-3.5 MHz| Inspire[DJI Inspire Mid-bandwidth]
    BWRange -->|3.5-5.0 MHz| MiniCheck[Check Mini vs others]
    BWRange -->|8.0-11.0 MHz| Phantom[DJI Phantom Classic OcuSync]
    BWRange -->|15.0-18.0 MHz| Mavic[DJI Mavic Highest BW]

    MiniCheck --> CPDet{CP Detected?}
    CPDet -->|No| MiniWiFi[DJI Mini 4.0 MHz WiFi]
    CPDet -->|Yes| OtherModel[Other DJI ~4 MHz]

    Air --> Confidence[+0.10 BW match bonus]
    Inspire --> Confidence
    Phantom --> Confidence
    Mavic --> Confidence
    MiniWiFi --> Confidence
    Mini --> Confidence

    style Air fill:#9cf,stroke:#333,stroke-width:2px
    style Inspire fill:#9cf,stroke:#333,stroke-width:2px
    style Phantom fill:#9cf,stroke:#333,stroke-width:2px
    style Mavic fill:#9cf,stroke:#333,stroke-width:2px
    style MiniWiFi fill:#fc9,stroke:#333,stroke-width:2px
                    

flowchart TD
    Start[900 MHz Signal] --> DualBand{Dual-band detected? 868-870 + 902-928 MHz}
    DualBand -->|Yes| Lancet[LANCET Dual-band LoRa confidence 0.85]

    DualBand -->|No| Mod[Modulation Analysis]
    Mod --> LoRa{LoRa CSS?}

    LoRa -->|Yes| HopRate{Hop Rate?}
    HopRate -->|40-60 Hz| LancetSingle[LANCET Single-band confidence 0.75]
    HopRate -->|25-500 Hz| Binding{Binding phrase hop pattern?}
    Binding -->|Yes| ELRS[ELRS Consumer/FPV confidence 0.75]
    Binding -->|No| Crossfire[CROSSFIRE ~50 Hz confidence 0.75]

    LoRa -->|No| FHSS{FHSS Pattern?}
    FHSS -->|Yes| HopSpeed{Hop Speed?}
    HopSpeed -->|1-2 Hz| Channels{Channel Count?}
    Channels -->|8-16| Orlan[ORLAN-10 Slow FHSS confidence 0.70]
    Channels -->|~10| Stripe{10-stripe pattern?}
    Stripe -->|Yes| Supercam[SUPERCAM Distinctive waterfall confidence 0.70]
    HopSpeed -->|~20 Hz| RFD900x[RFD900x Shahed mesh confidence 0.60]

    FHSS -->|No| FSK{FSK/DSSS?}
    FSK -->|Yes| BWNarrow{Bandwidth 200-400 kHz?}
    BWNarrow -->|Yes| OrlanLegacy[ORLAN-10 Legacy FSK confidence 0.60]
    BWNarrow -->|No| BWWide{Bandwidth ~5 MHz?}
    BWWide -->|Yes| SupercamWide[SUPERCAM Wide FHSS confidence 0.60]

    FSK -->|No| Power{Power Level?}
    Power -->|> -50 dBm| MilGeneric[MILITARY_UHF confidence 0.50]
    Power -->|< -50 dBm| D900[DRONE_900 confidence 0.40]

    style Lancet fill:#f33,stroke:#333,stroke-width:3px,color:#fff
    style LancetSingle fill:#f66,stroke:#333,stroke-width:2px
    style Orlan fill:#f96,stroke:#333,stroke-width:2px
    style Supercam fill:#fc6,stroke:#333,stroke-width:2px
    style ELRS fill:#9cf,stroke:#333,stroke-width:2px
    style Crossfire fill:#9cf,stroke:#333,stroke-width:2px
                    

flowchart TD
    Start[2.4 GHz Elevated Power] --> Occupancy{Wideband Occupancy >30% bins elevated?}

    Occupancy -->|Yes| FlatnessCheck{Power Flatness Peak-avg < 6 dB?}
    FlatnessCheck -->|Yes| WidebandJam[WIDEBAND JAMMING]
    FlatnessCheck -->|No| BW{Bandwidth?}

    BW -->|> 30 MHz| PossibleJam[Possible wideband - Check multi-band]
    BW -->|< 30 MHz| Drone[Likely drone signal]

    Occupancy -->|No| Narrow{Narrow peak >30 dB above avg?}
    Narrow -->|Yes| SpotJam[SPOT JAMMING]
    Narrow -->|No| Signal[Analyze as signal]

    Signal --> ModCheck{Modulation detected?}
    ModCheck -->|Yes| DJI[Drone - Confident]
    ModCheck -->|No| Temporal{Temporal stability?}
    Temporal -->|Stable| Drone2[Likely drone]
    Temporal -->|Swept/bursts| Jammer2[Likely jammer]

    PossibleJam --> MultiBand{Other bands active?}
    MultiBand -->|Yes 5.8 GHz| DJIVideo[DJI with video - NOT jammer]
    MultiBand -->|No| WidebandJam2[WIDEBAND JAMMING confirmed]

    style WidebandJam fill:#f33,stroke:#333,stroke-width:3px,color:#fff
    style SpotJam fill:#f33,stroke:#333,stroke-width:3px,color:#fff
    style WidebandJam2 fill:#f33,stroke:#333,stroke-width:3px,color:#fff
    style DJI fill:#9cf,stroke:#333,stroke-width:2px
    style DJIVideo fill:#9f9,stroke:#333,stroke-width:2px
                    

flowchart TD
    Start([Signal Features]) --> FreqScore[Frequency Match 0.35 weight]
    Start --> BWScore[Bandwidth Match 0.20 weight]
    Start --> ModScore[Modulation Match 0.25 weight]
    Start --> HopScore[Hop Rate Match 0.15 weight]
    Start --> SymScore[Symbol Rate Match 0.05 weight]
    Start --> CycloScore[Cyclostationary Bonus +0.10-0.15]
    Start --> MultiBandScore[Multi-Band Bonus +0.15-0.25]

    FreqScore --> Weights[Apply Weights]
    BWScore --> Weights
    ModScore --> Weights
    HopScore --> Weights
    SymScore --> Weights

    Weights --> BaseConf[Base Confidence = weighted_sum / total_weight]

    BaseConf --> Bonuses[Add Bonuses]
    CycloScore --> Bonuses
    MultiBandScore --> Bonuses

    Bonuses --> BeaconCheck{Beacon/Idle? BW < 50 kHz + SNR > 30 dB}
    BeaconCheck -->|Yes| BeaconCredit[+0.02 Beacon Credit Skip BW penalty]
    BeaconCheck -->|No| NoPenalty[No adjustment]

    BeaconCredit --> SNRGate{SNR < 10 dB?}
    NoPenalty --> SNRGate
    SNRGate -->|Yes| Cap35[Cap confidence at 0.35]
    SNRGate -->|No| NoSNRCap[No SNR cap]

    Cap35 --> MeasValid{Measurement valid?}
    NoSNRCap --> MeasValid
    MeasValid -->|No| Zero[Confidence = 0.0]
    MeasValid -->|Yes| Final[Final Confidence]

    Final --> Clamp[Clamp to 0.0-1.0]
    Clamp --> Output([Confidence Score])

    style Zero fill:#f33,stroke:#333,stroke-width:2px,color:#fff
    style Output fill:#9f9,stroke:#333,stroke-width:2px
                    

Max Tier Fusion Engine Diagram

flowchart TD
    Start([Multiple Sensor Inputs]) --> HealthCheck[Check Sensor Health Status]
    HealthCheck --> Fault{Any FAULT or DISCONNECTED?}
    Fault -->|Yes| Ignore[Ignore faulted sensors]
    Fault -->|No| AllOK[All sensors OK]

    Ignore --> Remaining{Any remaining sensors?}
    Remaining -->|No| Abort[No fusion possible]
    Remaining -->|Yes| Continue[Continue with healthy]
    AllOK --> Continue

    Continue --> Calib[Apply Calibration Normalization]
    Calib --> CorrWindow[Correlation Window +/- 2 seconds]

    CorrWindow --> FreqMatch{Frequency match across sensors?}
    FreqMatch -->|No| IndividualEvents[Independent events]
    FreqMatch -->|Yes| Correlate[Correlated Detection]

    Correlate --> TypeMatch{Same type across sensors?}
    TypeMatch -->|No| Generic[Generic type - Lower confidence]
    TypeMatch -->|Yes| Specific[Specific type - Higher confidence]

    Specific --> Weights[Compute Weighted Confidence]
    Generic --> Weights

    Weights --> PositionMethod[Select Position Method - 5-method priority]

    PositionMethod --> TDOACheck{3+ sensors all IN_SPEC?}
    TDOACheck -->|Yes| TDOAMethod[1. TDOA 10-50m]
    TDOACheck -->|No| DFCheck{2+ DF stations?}

    DFCheck -->|Yes| DFMethod[2. DF Bearing Intersection 50-200m]
    DFCheck -->|No| DFRSSICheck{1 DF + RSSI?}

    DFRSSICheck -->|Yes| DFRSSIMethod[3. DF+RSSI Hybrid 100-500m]
    DFRSSICheck -->|No| HybridCheck{2 sensors + timestamps?}

    HybridCheck -->|Yes| HybridMethod[4. Hybrid TDOA+RSSI 50-300m]
    HybridCheck -->|No| RSSI[5. RSSI Fallback 100-500m]

    TDOAMethod --> Output([FusedDetection])
    DFMethod --> Output
    DFRSSIMethod --> Output
    HybridMethod --> Output
    RSSI --> Output

    style Abort fill:#f33,stroke:#333,stroke-width:2px,color:#fff
    style Output fill:#9f9,stroke:#333,stroke-width:3px
                    

Time Sync & TDOA Eligibility Diagram

flowchart TD
    Start([Sensor Network]) --> SyncSource{Time Sync Source}

    SyncSource -->|GPS| GPSSync[GPS PPS - Nanosecond accuracy]
    SyncSource -->|NTP| NTPSync[NTP Server - Millisecond accuracy]
    SyncSource -->|PTP| PTPSync[PTP Protocol - Microsecond accuracy]
    SyncSource -->|DF_CLOCK| DFSync[Common Reference Osc - DF stations]
    SyncSource -->|None| NoSync[System Clock - Unsynchronized]

    GPSSync --> Quality[Measure Sync Quality]
    NTPSync --> Quality
    PTPSync --> Quality
    DFSync --> Quality
    NoSync --> Unknown[time_sync: UNKNOWN]

    Quality --> Drift{Clock Drift?}
    Drift -->|< 100 us| InSpec[IN_SPEC - TDOA eligible]
    Drift -->|100 us - 1 ms| OutSpec[OUT_OF_SPEC - TDOA NOT eligible]
    Drift -->|> 1 ms| Degraded[DEGRADED - TDOA NOT eligible]

    InSpec --> Fusion[DataFusion Engine]
    OutSpec --> Fusion
    Degraded --> Fusion
    Unknown --> Fusion

    Fusion --> Check{All contributors IN_SPEC?}
    Check -->|Yes| EnableTDOA[TDOA Triangulation 10-50m]
    Check -->|No| CheckDF{2+ sensors with DF bearings?}
    CheckDF -->|Yes| EnableDF[DF Bearing Intersection 50-200m]
    CheckDF -->|No| DisableTDOA[RSSI Fallback 100-500m]

    style InSpec fill:#9f9,stroke:#333,stroke-width:2px
    style EnableTDOA fill:#9f9,stroke:#333,stroke-width:2px
    style EnableDF fill:#9f9,stroke:#333,stroke-width:2px
    style DisableTDOA fill:#fc6,stroke:#333,stroke-width:2px
    style Unknown fill:#999,stroke:#333,stroke-width:2px,color:#fff
                    

Safety-Critical Gates Pipeline

flowchart TD
    Start([Detection Pipeline]) --> SNRCheck{SNR >= 10 dB?}
    SNRCheck -->|No| LowSNR[Cap confidence at 0.35]
    SNRCheck -->|Yes| Proceed[Proceed to classification]

    LowSNR --> MeasValid{Measurement valid?}
    Proceed --> MeasValid
    MeasValid -->|No| Reject[Confidence = 0.0 DO NOT CLASSIFY]
    MeasValid -->|Yes| Classify[Classification Engine]

    Classify --> BenignCheck{Benign filter match?}
    BenignCheck -->|Yes| Suppress{Multi-band or wideband FHSS?}
    Suppress -->|Yes| Override[Override benign - Multi-band NEVER suppressed]
    Suppress -->|No| Benign[Suppress as benign - Log at INFO]

    BenignCheck -->|No| Baseline[Compare to baseline]
    Override --> Baseline

    Baseline --> Anomaly{Anomaly detected?}
    Anomaly -->|Yes| FreezeBase[Freeze baseline 30s cooldown]
    FreezeBase --> CheckStale{Frozen > 120s?}
    CheckStale -->|Yes| Stale[Mark baseline stale - Sensor DEGRADED]
    CheckStale -->|No| Valid[Continue detection]
    Anomaly -->|No| Valid

    Valid --> CalibCheck{Calibrated?}
    CalibCheck -->|No| Uncalib[50% confidence penalty]
    CalibCheck -->|Yes| Calib[Full confidence]

    Uncalib --> ConfigCheck{Config signed?}
    Calib --> ConfigCheck
    ConfigCheck -->|No| ConfigWarn{REQUIRE_SIGNED?}
    ConfigWarn -->|Yes| ConfigFail[SENSOR_FAILURE Config integrity error]
    ConfigWarn -->|No| ConfigCont[Continue with warning]
    ConfigCheck -->|Yes| Provenance[Attach provenance]
    ConfigCont --> Provenance

    Provenance --> HardwareFault{Hardware fault?}
    HardwareFault -->|Yes| Failure[SENSOR_FAILURE NEVER return CLEAR]
    HardwareFault -->|No| ThreatEvent[ThreatEvent]

    style Reject fill:#f33,stroke:#333,stroke-width:2px,color:#fff
    style Failure fill:#f33,stroke:#333,stroke-width:2px,color:#fff
    style ConfigFail fill:#f33,stroke:#333,stroke-width:2px,color:#fff
    style ThreatEvent fill:#9f9,stroke:#333,stroke-width:2px
                    

Acoustic ML Pipeline

flowchart TD
    Mic([USB MEMS Microphone]) --> Preprocess[Audio Preprocessing
16 kHz, mono, 2s frames]
    Preprocess --> MFCC[MFCC Feature Extraction
40 coefficients + delta + delta-delta]

    MFCC --> Stage1{Stage 1: Fingerprint Match
Known acoustic signatures?}
    Stage1 -->|Yes| FPMatch[Fingerprint Match
High confidence shortcut]
    Stage1 -->|No| Stage2

    FPMatch --> Output

    Stage2{Stage 2: Threshold Gates
Class-generic energy thresholds}
    Stage2 -->|Below threshold| Background[Background Noise
No detection]
    Stage2 -->|Above threshold| Stage3

    Stage3[Stage 3: ResNet-18 Inference
88.9% overall accuracy]
    Stage3 --> Classes{Classification}
    Classes --> Shahed[Shahed/Fixed-wing
92.3% recall]
    Classes --> Quad[Quadcopter
90.9% recall]
    Classes --> Heli[Helicopter
Retraining target]
    Classes --> Other[Other classes]

    Shahed --> Output([Acoustic Detection Event])
    Quad --> Output
    Heli --> Output
    Other --> Output

    Output --> Fusion[RF-Acoustic Bayesian Fusion
Supplementary only]

    style Background fill:#666,stroke:#333,stroke-width:2px,color:#fff
    style Output fill:#9f9,stroke:#333,stroke-width:2px
    style FPMatch fill:#9cf,stroke:#333,stroke-width:2px
                    

RemoteID Correlation Flow

flowchart TD
    BLE([BLE RemoteID
~100m range]) --> Correlator
    WiFi([WiFi RemoteID Bridge
Extended range]) --> Correlator
    DJI([DJI DroneID / OcuSync
I/Q decode]) --> Correlator

    Correlator[RemoteID Correlator
Match RF detections ±10s window]

    Correlator --> Match{RemoteID match
found?}
    Match -->|Yes| AntiSpoof{Anti-Spoof
Validation}
    Match -->|No| DarkDrone[Dark Drone Alert
Threat level escalated]

    AntiSpoof --> RFCheck[RF Band
Consistency Check]
    AntiSpoof --> Motion[Motion
Plausibility Analysis]
    AntiSpoof --> Operator[Operator Distance
Verification]

    RFCheck --> Score{Spoof Score}
    Motion --> Score
    Operator --> Score

    Score -->|Score >= 0.4| Compliant[Compliant Drone
Blue marker on map]
    Score -->|Score < 0.4| Spoofed[Suspected Spoof
Escalated + flagged]

    DarkDrone --> Tactical([Tactical Display
Red marker + alert])
    Compliant --> Tactical
    Spoofed --> Tactical

    style DarkDrone fill:#f66,stroke:#333,stroke-width:2px
    style Spoofed fill:#f96,stroke:#333,stroke-width:2px
    style Compliant fill:#9f9,stroke:#333,stroke-width:2px
    style Tactical fill:#9cf,stroke:#333,stroke-width:2px