Wireless Sensor Network (WSN) Kit Documentation

Wireless Sensor Network (WSN) is a system of spatially distributed sensor nodes that wirelessly collect and transmit data to a central server for monitoring, analysis, and visualization.

1. Overview

The WSN Kit is a modular wireless sensor network system designed for educational and experimental use. It includes:

5 Sensor Nodes (based on NodeMCU ESP8266)
2 Repeater Nodes (based on NodeMCU ESP8266)
1 Center Server Node (based on Raspberry Pi)
Desktop GUI for real-time network and data visualization

2. System Architecture

The system follows a hierarchical network model:

Sensor Nodes transmit data to Repeater Nodes
Repeater Nodes forward the data to the Center Server
The Server Node store, processes and visualizes the data with the Desktop GUI

Important Notes:

Sensor → Repeater (one-way)
Repeater → Server (one-way)
No direct Sensor ↔ Server communication
Each Sensor connects to only one Repeater
Each Repeater connects to only one Repeater/Server

3. Components

Component	Quantity	Platform	Description
Sensor Node	5	NodeMCU ESP8266	Equipped with environmental sensors
Repeater Node	2	NodeMCU ESP8266	Relays data to the Server
Server Node	1	Raspberry Pi	Collects, stores, and visualizes data
Desktop GUI	1	Cross-platform	Shows node and connection statuses

4. Sensor Types Used

Each sensor node in the WSN Kit is equipped with one or more of the following sensors:

HR202 Humidity Sensor – Detects ambient humidity levels.
DS18B20 Waterproof Temperature Sensor – Measures temperature in harsh or wet environments.
M12 Smoke Sensor – Detects smoke presence in the air.
LDR (Light Dependent Resistor) – Measures light intensity.
Push Button – Used as a manual trigger to activate a buzzer.

These sensors help demonstrate different real-world use cases such as environmental monitoring, fire detection, and user interaction.

5. Connection Flow Diagram

Sensor Node (S1) ---> Repeater Node (R1)
Sensor Node (S2) ---> Repeater Node (R1)
Sensor Node (S3) ---> Repeater Node (R2)
Sensor Node (S4) ---> Repeater Node (R2)
Sensor Node (S5) ---> Repeater Node (R2)

Repeater Node (R1) ---> Server (Raspberry Pi)
Repeater Node (R2) ---> Server (Raspberry Pi)

6. Installation Guide

Flash firmware on NodeMCU sensor and repeater nodes.
Configure MQTT or custom protocol for node communication.
Set up Raspberry Pi as server and install GUI software.
Power up nodes in this order: Server → Repeater → Sensor

7. Desktop GUI Features

Live topology map
Real-time data stream view
Connection status indicators
Node configuration panel

8. Notes

Make sure each sensor is uniquely addressed.
Only one repeater should handle a sensor's data.
GUI updates every 5 seconds (customizable).