| Title | Author | Created | Published | Tags | | -------------------------- | ---------------------------- | ------------ | ------------ | ------------------------ | | System Architecture Report | <ul><li>Jon Marien</li></ul> | May 20, 2025 | May 20, 2025 | [[#capstone\|#capstone]] | # Group 7 – Enhancing Automotive Security ## System Architecture Report * *Lead Programmer – Jonathan Marien, 991476393*<br> * *Project Lead – Jillian Moorcroft, 991625656*<br> * *Lead Researcher – Aaron Briand, 991644564* <br> * *Researcher – Hala Alwash, 991471580* --- # Overview The capstone delivers a USB-powered radio-frequency (RF) monitoring dongle that listens on 315 MHz, 433 MHz, and 13.56 MHz to flag relay, cloning, and jamming attempts against keyless-entry vehicles. Alerts are forwarded to drivers through a mobile application while optionally streaming anonymized telemetry to a cloud dashboard for aggregated fleet analytics. ## High-Level System Architecture The complete solution is composed of eight tightly-coupled functional blocks that exchange signed JSON messages across secure local or cloud channels. ```md ┌─────────────────────────────────────────────────────────────────────────────┐ │ VEHICLE CABIN │ │ │ │ ┌───────────┐ Coax ┌────────────┐ IQ Stream ┌────────────┐ │ │ │ Antenna ├──────────►│ SDR Core ├──────────────►│ Edge MCU │ │ │ └───────────┘ └────────────┘ └─────┬──────┘ │ │ ▲ USB │ │ │ │ │ │ │ ┌────────────┐ SPI/I²C ┌──────────┴─────┐ │ │ │ Secure Elem│◄────────────│ BLE/Wi-Fi SoC │ │ │ └────────────┘ └─────┬─────────┘ │ │ ▲ UART/BLE │ │ │ │ │ │ │ ┌────────────┐ │ │ │ │ NFC Coil │ │ │ │ └────────────┘ │ │ │ ▲ NFC │ │ │ │ │ │ │ ┌────────────┐ │ │ │ │ Mobile App │◄───────────────────┘ │ │ └────────────┘ BLE/GATT or MQTT │ │ │ │ OTA / TLS1.3 │ │ │ │ │ ▼ │ │ ┌────────────┐ │ │ │ Cloud API │ │ │ └────────────┘ │ └─────────────────────────────────────────────────────────────────────────────┘ ``` ### **Key relationships** • Antenna feeds an SDR core that streams IQ data to a micro-controller for spectral analysis. • The micro-controller’s anomaly engine forwards events to the BLE/Wi-Fi module; this module bridges to the mobile app and (optionally) an MQTT broker in the cloud. • A hardware secure-element protects TLS keys used for firmware updates, mobile pairing, and cloud upload, guaranteeing provenance and preventing replay attacks. ## Functional Block Summary | # | Block | Core Technology | Principal Role | Notable Interfaces | | --- | -------------------- | ----------------- | ------------------------------------------- | --------------------------------- | | 1 | Antenna & Front-End | SAW filters + LNA | Capture 315/433 MHz & 13.56 MHz | Coax → SDR | | 2 | SDR Core | RTL-SDR V3 (USB) | Digitise baseband, 2 MS/s | USB 2.0 OTG → MCU | | 3 | Edge Compute | Raspberry Pi 4B | FFT & lightweight CNN for anomaly detection | SPI to secure element; USB to SDR | | 4 | Secure Storage | ATECC608B | Key vault, secure-boot attestation | I²C to Pi | | 5 | BLE/Wi-Fi SoC | ESP32-C3 | Low-latency alert channel + OTA | UART to Pi; BLE to phone | | 6 | Mobile Application | Flutter | Push notifications, logs, settings | BLE; REST to cloud | | 7 | Cloud API (optional) | AWS IoT Core | Fleet analytics & threat-intel share | MQTT/TLS | | 8 | Power Management | 2 000 mAh Li-ion | 48 h standby after USB loss | I²C fuel gauge | ## Data-Flow Description 1. Raw RF bursts enter the SDR, are digitized, and streamed to the Pi’s ring buffer where a lightweight CNN classifies patterns against a curated dataset of legitimate key-fob bursts. 2. Any suspicious frame (e.g., high RSSI replay with abnormal preamble) is wrapped in a signed JSON object and queued to the ESP32. 3. The ESP32 notifies the mobile app in ≤ 3 s via BLE GATT; parallel TLS 1.3 upload to the cloud enables fleet security-operation-centre dashboards. 4. On receiving a critical alert, the app can sound an alarm, display direction-finding hints, and optionally trigger a CAN-bus immobilizer via OEM API partnerships. ## Security Controls Aligned to ISO/SAE 21434 | Clause | Control Implemented | Work Product | |--------|--------------------|--------------| | 10.5 | Secure-boot chain validates Pi & ESP32 firmware on power-up | WP-10-03 – Coding-guideline docs | | 10.7 | Static-analysis + fuzzing to minimise residual weaknesses | WP-10-07 – Vulnerability report | | 11.1 | Vehicle-level validation with replay attacks against demo cars | WP-11-01 – Validation report | | 13 | Incident-response playbook for OTA hot-patches | WP-13-02 – Update procedure | ## Bill-of-Materials Snapshot *What we have:* | Category | Part/Item | Qty | Unit Cost (CAD) | Source | | -------------- | ------------------- | --- | --------------- | ---------------- | | Board | Board w Accessories | 1 | $48.30 | (as per receipt) | | Board | Back-up Board | 1 | $11.95 | (as per receipt) | | Misc. | Dongle Ext. x2 | 2 | $8.50 | (as per receipt) | | SDR | RTL-SDR | 1 | $69.95 | (as per receipt) | | NFC | NFC Module | 1 | $15.99 | (as per receipt) | | Shipping | PiShop Shipping | 1 | $17.12 | (as per receipt) | | Tax | PiShop Tax | 1 | $8.94 | (as per receipt) | | Import Fees | Import Fees Amazon | 1 | $11.18 | (as per receipt) | | **Total** | | | **$191.93** | | | **Per Person** | | | **$47.98** | (4 people) | *What we may need:* | Category | Part | Qty | Unit Cost (CAD) | Source | | -------------- | ------------------------------- | --- | --------------- | ---------- | | Secure Element | Microchip ATECC608B-MAHDA | 1 | 1.20 | Mouser | | Power | 2 000 mAh Li-ion cell + charger | 1 | 7.20 | AliExpress | | Enclosure | 3-D-printed PETG shell | 1 | 3.00 | In-house | | Misc. | Cables, headers, passives | — | 5.65 | — | | **Total** | | | **CAN $17.05** | | ## Future Enhancements * Direction-finding using AoA with dual coherent antennas * Integration with OEM telematics for automatic immobiliser engagement * Expansion to 868 MHz/915 MHz for European key-fobs * Integration of Tiny-ML-based classification directly on ESP32 C6 to remove Raspberry Pi dependency --- ### References 1. ISO/SAE 21434:2021 – Road Vehicles – Cybersecurity Engineering. 2. ETSI EN 303 204 V2.2.1 – Short Range Device Radio Equipment. 3. RTL-SDR Blog. “V4 Dongle Specifications,” 2024.