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OpenWiFi System Design Documentation

1. System Overview

OpenWiFi is an open-source implementation of the IEEE 802.11 WiFi protocol stack, supporting both hardware and software components. The system enables wireless communication following WiFi standards while providing flexibility for customization and enhancement.

1.1 Key Features

  • IEEE 802.11 protocol compliance
  • Support for multiple frequency bands
  • Hardware abstraction layer
  • Configurable protocol stack
  • Real-time signal processing
  • Security protocol implementation

2. Architecture Overview

2.1 High-Level System Architecture

graph TB
    subgraph "Applications Layer"
        APP[User Applications]
        MGMT[Management Tools]
        CFG[Configuration Interface]
    end

    subgraph "Protocol Stack"
        MAC[MAC Layer]
        PHY[PHY Layer]
        SEC[Security Module]
        DRV[Device Drivers]
    end

    subgraph "Hardware Layer"
        FPGA[FPGA/DSP]
        RF[RF Frontend]
        ANT[Antenna System]
    end

    APP --> MGMT
    MGMT --> CFG
    CFG --> MAC
    MAC --> PHY
    MAC --> SEC
    PHY --> DRV
    DRV --> FPGA
    FPGA --> RF
    RF --> ANT

2.2 Component Interactions

graph LR
    subgraph "Control Plane"
        CTRL[Control Unit]
        CFG[Configuration]
        MON[Monitoring]
    end

    subgraph "Data Plane"
        BUF[Buffer Management]
        PROC[Packet Processing]
        QOS[QoS Engine]
    end

    CTRL --> CFG
    CFG --> MON
    BUF --> PROC
    PROC --> QOS

3. Component Details

3.1 MAC Layer Architecture

graph TD
    subgraph "MAC Layer Components"
        MCTRL[MAC Controller]
        FRAME[Frame Management]
        AGG[Frame Aggregation]
        RETR[Retransmission Unit]
        QUEUE[Queue Management]
    end

    MCTRL --> FRAME
    FRAME --> AGG
    AGG --> RETR
    RETR --> QUEUE

3.2 PHY Layer Implementation

graph LR
    subgraph "PHY Processing"
        MOD[Modulation]
        ENC[Encoding]
        FFT[FFT/IFFT]
        CP[Cyclic Prefix]
    end

    MOD --> ENC
    ENC --> FFT
    FFT --> CP

4. Communication Flows

4.1 Data Transmission Sequence

sequenceDiagram
    participant App
    participant MAC
    participant PHY
    participant RF

    App->>MAC: Data Packet
    MAC->>MAC: Add Headers
    MAC->>PHY: Frame
    PHY->>PHY: Signal Processing
    PHY->>RF: IQ Samples
    Note over RF: Transmission

4.2 Connection Establishment

sequenceDiagram
    participant Client
    participant AP
    participant Auth

    Client->>AP: Discovery
    AP->>Client: Beacon
    Client->>AP: Authentication Request
    AP->>Auth: Validate
    Auth->>AP: Confirm
    AP->>Client: Authentication Response
    Client->>AP: Association Request
    AP->>Client: Association Response

5. Technical Specifications

5.1 Hardware Requirements

  • FPGA/DSP processing capabilities
  • RF frontend supporting required frequency bands
  • Minimum RAM: 512MB
  • System clock: 200MHz+
  • ADC/DAC resolution: 12-bit minimum

5.2 Software Requirements

  • Real-time operating system support
  • Driver compatibility with target hardware
  • Protocol stack implementation
  • Management interface

6. Implementation Guidelines

6.1 Development Stack

  • FPGA development tools
  • SDR framework compatibility
  • Software development environment
  • Testing and verification tools

6.2 Coding Standards

  • Hardware description language guidelines
  • Software coding conventions
  • Documentation requirements
  • Version control procedures

7. Security Considerations

7.1 Security Architecture

graph TD
    subgraph "Security Framework"
        AUTH[Authentication]
        CRYPT[Encryption]
        KEY[Key Management]
        IDS[Intrusion Detection]
    end

    AUTH --> CRYPT
    CRYPT --> KEY
    KEY --> IDS

7.2 Security Features

  • WPA3 support
  • Protected Management Frames
  • Secure key generation
  • Replay protection
  • Access control mechanisms

8. Performance Metrics

8.1 Key Performance Indicators

  • Throughput: Up to 1Gbps
  • Latency: < 2ms
  • Packet loss: < 0.1%
  • Connection stability: 99.9%
  • Power efficiency metrics

8.2 Monitoring and Optimization

graph LR
    subgraph "Performance Monitoring"
        PERF[Performance Monitor]
        STAT[Statistics Collection]
        ANAL[Analysis Engine]
        OPT[Optimization Unit]
    end

    PERF --> STAT
    STAT --> ANAL
    ANAL --> OPT

9. Future Considerations

9.1 Roadmap

  • Enhanced MIMO support
  • Advanced beamforming
  • AI/ML integration
  • Power optimization
  • Protocol extensions

9.2 Scalability

  • Multi-user support
  • Channel bonding
  • Spatial multiplexing
  • Network capacity expansion