SuperNicePCB

UWB Anchor & Indoor Human Occupancy Tracking Station

An integrated, multi-sensor UWB anchor PCB designed for real-time indoor object tracking (via Double-Sided Two-Way Ranging) and non-invasive human presence/occupancy monitoring. Built on a compact 75 × 85 mm² 4-layer stackup, this node timestamps sensor data with microsecond precision via Wi-Fi TSF and streams payload telemetry to a central data fusion server.

Table of Contents

• Project Overview
• Key Features
• Hardware & Bill of Materials
• Sensor Matrix
• Time Synchronization Strategy
• PCB Design & Stackup
• Repository Structure
• Team & Course Credits

Project Overview

This project implements an open-hardware anchor node for spatial localization and environmental occupancy analytics. The node performs two core functions simultaneously:

1. Ultra-Wideband (UWB) Ranging: Acts as a fixed anchor measuring distances to mobile UWB tags using IEEE 802.15.4z DS-TWR.
2. Multi-Variable Human Sensing: Tracks room occupancy trends and movement through non-camera environmental sensors (CO₂, Temperature/Humidity, Acoustic level, PIR motion, and mmWave micro-movement radar).

All gathered metrics are bound to a unified global timebase and transmitted over a 2.4 GHz Wi-Fi network (UDP/TCP) to a host server executing sensor-fusion algorithms.

Key Features

• High-Performance MCU: ESP32-S3-WROOM-1-N8 (Dual-core Xtensa LX7 @ 240 MHz, 512 kB SRAM, 8 MB Flash, native USB CDC/JTAG).
• Precision UWB Transceiver: Decawave DWM3000TR13 (DW3110 engine) over SPI, supporting channels 5 (6.5 GHz) and 9 (8.0 GHz) with integrated antenna and keep-out area.
• Dual 3.3V Power Domain Architecture: Dedicated high-efficiency DC-DC Buck converter power rail for MCU processing and wireless transmission current spikes, combined with an isolated low-noise LDO regulator power rail for the sensitive sensor matrix.
• Privacy-Preserving Human Detection: Multi-variable sensing without optical cameras.
• Microsecond Timestamping: Hardware Wi-Fi TSF timer (esp_wifi_get_tsf_time()) combined with periodic NTP/SNTP synchronization.

Hardware & Bill of Materials

Sensor Matrix

1. Decawave DWM3000 UWB: Configured for Double-Sided Two-Way Ranging (DS-TWR) operating at 5 - 20 Hz update rates per tag.
2. Sensirion SCD40: Measures ambient CO₂ concentration every 30 - 60 s as an indicator of human breathing density.
3. Sensirion SHT40: Provides high-accuracy ambient thermal/humidity telemetry (±0.2 °C, ±1.8% RH) to complement indoor air comfort models.
4. TDK ICS-43434: Samples acoustic sound pressure over sliding time windows to determine room activity levels.
5. AM312 PIR: Digital motion trigger generating interrupts upon macroscopic body movement.
6. mmWave Radar Module: Captures fine target presence, velocity, and chest micro-movements (respiration) via continuous UART streaming.

Time Synchronization Strategy

To ensure precise multi-anchor data alignment on the host processing server:

1. Coarse Clock Sync (NTP/SNTP): Upon Wi-Fi connection, the anchor queries an NTP server to calibrate epoch time.
2. Fine-Grain Microsecond Timing (Wi-Fi TSF): Each sensor frame is tagged using esp_wifi_get_tsf_time(), providing absolute microsecond precision relative to the Wi-Fi Access Point Timing Synchronization Function.
3. Fallback Mode (ESP-NOW): In ad-hoc deployments without an infrastructure AP, an ESP-NOW broadcast timesync protocol is utilized.

PCB Design & Stackup

• Dimensions: 75 × 85 mm²
• Layer Count: 4 Layers (Mixed RF + High-Speed Digital)
• Layer Assignment:
  • L1 (Top): Component placement, high-speed signals (SPI, I²S, USB 90 Ω diff pair), RF traces.
  • L2 (GND): Continuous Solid Ground Plane.
  • L3 (Power): Split power planes with dual 3.3V power domains (3.3V_MCU from Buck, 3.3V_SENSOR from LDO).
  • L4 (Bottom): Secondary routing and test points.
• RF Guidelines: 50 Ω coplanar waveguide routing for UWB antenna path with explicit ground keep-out regions under the chip antenna area.

Repository Structure

├── docs/
│   ├── schematics/             # PDF Schematics
│   └── specifications/         # ECAM Project Brief & Specs
├── hardware/
│   ├── gerber/                 # Production fabrication files
│   ├── KiCad/                  # Project files (.kicad_pro, .kicad_sch, .kicad_pcb)
│   └── bom/                    # Bill of Materials (CSV/JLCPCB format)
├── firmware/
│   ├── main/                   # ESP-IDF / Arduino source code
│   └── components/             # Custom drivers for SCD40, DWM3000, ICS-43434
└── README.md

Team & Course Credits

Course: Advanced PCB Design (Academic Year 2026–2027)
Institution: ECAM Brussels Engineering School

Group Members:

• Laurent Emond
• Vincenzo Acquaviva
• Lincoln Lassey
• Mathieu Mascot

ECAM Engineering Department