Detailed WiFi Operation Workflows Documentation

1. Detailed Data Transmission Path

sequenceDiagram
    participant APP as Application Layer
    participant DRV as Driver
    participant MAC as MAC Layer
    participant SEC as Security Module
    participant PHY as PHY Layer
    participant RF as RF Frontend

    Note over APP,RF: Transmission Path

    APP->>DRV: Application Data
    DRV->>DRV: Create Socket Buffer
    DRV->>MAC: Submit Data Frame

    MAC->>MAC: Frame Classification
    MAC->>MAC: QoS Mapping
    MAC->>MAC: Frame Assembly
    MAC->>MAC: Add MAC Header

    MAC->>SEC: Request Encryption
    SEC->>SEC: Generate IV/Nonce
    SEC->>SEC: Apply Encryption
    SEC->>SEC: Calculate MIC
    SEC->>MAC: Protected Frame

    MAC->>PHY: PHY Frame Request

    PHY->>PHY: Add PHY Header
    PHY->>PHY: Scrambling
    PHY->>PHY: FEC Encoding
    PHY->>PHY: Interleaving
    PHY->>PHY: Constellation Mapping
    PHY->>PHY: Pilot Insertion
    PHY->>PHY: IFFT Processing
    PHY->>PHY: CP Insertion
    PHY->>PHY: Windowing

    PHY->>RF: IQ Samples
    RF->>RF: Digital Up-Conversion
    RF->>RF: DAC Processing
    RF->>RF: RF Up-Conversion
    RF->>RF: Power Amplification

    Note over APP,RF: Transmission Complete

2. Channel Access Sequence with EDCA

sequenceDiagram
    participant MAC as MAC Layer
    participant EDCA as EDCA Controller
    participant CCA as CCA Monitor
    participant TMR as Timer
    participant TX as Transmitter

    Note over MAC,TX: Channel Access Procedure

    MAC->>EDCA: Frame Ready (AC_XX)
    EDCA->>EDCA: Load EDCA Parameters
    Note over EDCA: AIFSN, CWmin, CWmax

    EDCA->>CCA: Request Channel Status
    CCA->>EDCA: Channel Status Report

    alt Channel Busy
        EDCA->>EDCA: Freeze Backoff
        EDCA->>CCA: Continue Monitoring
    else Channel Idle
        EDCA->>EDCA: Calculate Backoff
        EDCA->>TMR: Start AIFS Timer
        TMR->>EDCA: AIFS Complete

        loop Backoff Procedure
            EDCA->>TMR: Start Slot Timer
            TMR->>EDCA: Slot Complete
            EDCA->>CCA: Check Channel

            alt Channel Remains Idle
                EDCA->>EDCA: Decrement Counter
            else Channel Becomes Busy
                EDCA->>EDCA: Freeze Counter
                EDCA->>CCA: Wait for Idle
            end
        end
    end

    EDCA->>TX: Grant Transmission
    TX->>MAC: Transmission Complete

    Note over MAC,TX: Channel Access Complete

3. Multi-User MIMO Operation

sequenceDiagram
    participant AP as Access Point
    participant SM as Spatial Mapping
    participant STA1 as Station 1
    participant STA2 as Station 2
    participant STA3 as Station 3

    Note over AP,STA3: MU-MIMO Setup and Operation

    AP->>AP: Initialize MU-MIMO

    par Sounding Phase
        AP->>STA1: NDP Announcement
        AP->>STA2: NDP Announcement
        AP->>STA3: NDP Announcement
        AP->>AP: Transmit NDP
    end

    par CSI Feedback
        STA1->>AP: Compressed Beamforming
        STA2->>AP: Compressed Beamforming
        STA3->>AP: Compressed Beamforming
    end

    AP->>SM: Process CSI Matrices
    SM->>SM: Calculate Steering Matrices
    SM->>AP: Precoding Information

    AP->>AP: Group Formation
    AP->>AP: Resource Allocation

    par Data Transmission
        AP->>STA1: Spatial Stream 1
        AP->>STA2: Spatial Stream 2
        AP->>STA3: Spatial Stream 3
    end

    par Acknowledgment
        STA1->>AP: Multi-STA BlockAck
        STA2->>AP: Multi-STA BlockAck
        STA3->>AP: Multi-STA BlockAck
    end

    Note over AP,STA3: MU-MIMO Transaction Complete

4. Power Save Operation

sequenceDiagram
    participant STA as Station
    participant PSM as Power Save Manager
    participant BUF as AP Buffer
    participant AP as Access Point
    participant TIM as TIM/DTIM Generator

    Note over STA,TIM: Power Save Cycle

    STA->>PSM: Request PS Mode
    PSM->>PSM: Save Current State
    PSM->>AP: PS-Poll Frame

    AP->>BUF: Enable Frame Buffering
    AP->>TIM: Update TIM Bitmap

    loop Beacon Interval
        AP->>TIM: Generate Beacon
        TIM->>TIM: Set TIM/DTIM Elements
        AP->>STA: Beacon with TIM

        alt Traffic Buffered
            STA->>PSM: Wake Up Radio
            PSM->>AP: PS-Poll Frame
            AP->>BUF: Retrieve Buffered Frame
            AP->>STA: Buffered Data
            STA->>AP: ACK

            alt More Data Flag Set
                STA->>AP: Additional PS-Poll
            else No More Data
                STA->>PSM: Return to Sleep
            end
        else No Traffic
            STA->>PSM: Maintain Sleep
        end
    end

    Note over STA,TIM: Power Save Cycle Complete

5. Rate Adaptation Process

sequenceDiagram
    participant MAC as MAC Layer
    participant RA as Rate Adaptation
    participant STAT as Statistics Engine
    participant PHY as PHY Layer
    participant CH as Channel Monitor

    Note over MAC,CH: Rate Adaptation Cycle

    MAC->>STAT: Request Performance Stats
    STAT->>RA: Provide PER Data
    CH->>RA: Channel Quality Metrics

    RA->>RA: Calculate Success Rate
    RA->>RA: Analyze Trends

    loop Rate Decision
        RA->>RA: Check Thresholds

        alt Excellent Conditions
            RA->>RA: Consider Rate Increase
            RA->>PHY: Probe Higher Rate
            PHY->>STAT: Monitor Success

            alt Probe Successful
                RA->>PHY: Confirm Rate Increase
            else Probe Failed
                RA->>PHY: Revert Rate
            end

        else Poor Conditions
            RA->>RA: Calculate Fallback Rate
            RA->>PHY: Apply Lower Rate
            PHY->>STAT: Monitor Recovery
        end
    end

    PHY->>MAC: Update Rate Selection
    MAC->>MAC: Apply New Rate

    Note over MAC,CH: Rate Adaptation Complete