366  WSN Deployment and Sizing Guide

Prerequisites: WSN Overview | WSN Sensor Nodes

Part of: Wireless Sensor Networks series

This enables: WSN Energy Management

366.1 WSN Deployment Sizing Guide

⏱️ ~8 min | ⭐⭐ Intermediate | πŸ“‹ P05.C25.U05

Practical guidance for planning WSN deployments based on application requirements:

366.1.1 Agricultural Monitoring Example

Requirements: - Field: 100 hectares (1 kmΒ²) - Sensors: Soil moisture, temperature, humidity - Coverage: 1 sensor per 50m Γ— 50m grid - Lifetime: 2 years without battery replacement - Budget: $50,000

Deployment Calculation:

Area Coverage:
1,000,000 mΒ² / (50m Γ— 50m per sensor) = 400 sensor nodes

Network Topology:
- 400 sensors organized into 20 clusters (20 nodes each)
- 20 cluster heads (solar-powered gateways)
- 1 main gateway with cellular uplink to cloud

Hardware Selection:
Sensor Node: Arduino + LoRa + Soil sensor
- Cost: $35/node Γ— 400 = $14,000
- Battery: 2Γ— AA (3000 mAh) β†’ 2-year life at 1% duty cycle

Cluster Head: Raspberry Pi + LoRa + Solar
- Cost: $120/node Γ— 20 = $2,400
- Power: Solar panel + battery (infinite lifetime)

Main Gateway: Industrial PC + 4G LTE
- Cost: $800 Γ— 1 = $800
- Connectivity: $50/month Γ— 24 months = $1,200

Total Cost: $14,000 + $2,400 + $800 + $1,200 = $18,400 (within budget!)

Data Flow:
400 sensors β†’ (LoRa) β†’ 20 cluster heads β†’ (Wi-Fi) β†’ Main gateway β†’ (4G) β†’ Cloud
Traffic: 400 sensors Γ— 1 msg/10min Γ— 50 bytes = 120 KB/hour β†’ 3 MB/day
Cellular cost: 3 MB/day Γ— 30 days = 90 MB/month (~$50/month)

366.1.2 Industrial Monitoring Example

Requirements: - Factory: 10,000 mΒ² (single building) - Sensors: Temperature, vibration, gas detection - Coverage: 100 sensors (critical equipment monitoring) - Latency: <1 second for gas alerts - Uptime: 99.9% (mission-critical)

Deployment Calculation:

Reliability Requirements:
99.9% uptime = 8.76 hours/year downtime max
β†’ Requires redundant architecture

Network Topology:
- 100 sensors (mains-powered, no battery constraint)
- 2 redundant gateways (active-active failover)
- Gigabit Ethernet backbone (factory LAN)
- Cloud backup (optional)

Hardware Selection:
Sensor Node: ESP32 + Zigbee + Industrial sensors
- Cost: $60/node Γ— 100 = $6,000
- Power: 5V DC from factory power
- Network: Zigbee mesh (2.4 GHz)

Gateway: Dell Edge Gateway 5000 (ruggedized)
- Cost: $1,200 Γ— 2 (redundancy) = $2,400
- Connectivity: Dual Ethernet (primary + backup)
- Monitoring: Automatic failover (<1 second)

Local Server: Industrial PC (on-premise data storage)
- Cost: $3,000 Γ— 1 = $3,000
- Purpose: Local SCADA, no cloud dependency

Total Cost: $6,000 + $2,400 + $3,000 = $11,400

Latency Analysis:
Sensor detects gas leak β†’ Zigbee mesh (10ms) β†’ Gateway (5ms processing) β†’
Ethernet (1ms) β†’ Local alarm system (TOTAL: <20ms) βœ“ Meets <1s requirement

No cloud dependency β†’ 99.9% uptime achievable (only local failures, not internet)

366.1.3 Sizing Rules of Thumb

Metric Low Density Medium Density High Density
Node spacing 100m 50m 20m
Nodes per gateway 10-20 50-100 200-500
Gateway spacing 500m (outdoor) 50m (indoor) 20m (dense indoor)
Cluster size 5-10 nodes 20-30 nodes 50-100 nodes
Battery lifetime 5 years (outdoor) 2-3 years (frequent reporting) Mains power (critical)

366.2 What’s Next?

Deepen your WSN expertise: