WiFi Site Survey Guidelines

Introduction to WiFi Site Surveys

A WiFi site survey is a critical process for planning, designing, and optimizing wireless networks. It involves analyzing the physical location where the WiFi network will be deployed to determine the optimal placement of access points, identify potential sources of interference, and ensure adequate coverage and capacity. This article provides comprehensive guidelines for conducting effective WiFi site surveys.

Why Conduct a WiFi Site Survey?

Many organizations make the mistake of installing wireless access points without proper planning, leading to coverage gaps, interference issues, and poor performance. A thorough site survey helps you:

• Determine the optimal number and placement of access points
• Identify and mitigate sources of interference
• Plan for appropriate capacity based on user density and requirements
• Ensure seamless roaming between access points
• Validate wireless network performance against requirements
• Reduce costs by avoiding unnecessary hardware

Types of WiFi Site Surveys

1. Predictive Site Survey

A predictive survey uses specialized software to create a virtual model of your facility and simulate WiFi coverage.

When to use:

• For initial planning of new deployments
• When physical access to the site is limited
• For large facilities where manual surveys would be time-consuming
• When working with buildings still under construction

Limitations:

• Relies on accurate floor plans and building material information
• Cannot account for all real-world variables
• Should be validated with on-site measurements

2. Manual (Active) Site Survey

A manual survey involves physically walking through the facility with WiFi equipment to measure actual signal strength, noise levels, and performance.

When to use:

• For final validation of network design
• When troubleshooting existing WiFi issues
• In environments with unique characteristics not easily modeled
• When high precision is required

Process:

• Set up temporary access points at planned locations
• Walk through the facility with a device running site survey software
• Collect data on signal strength, noise, interference, and data rates
• Adjust access point placement based on findings

3. Passive Site Survey

A passive survey involves listening to existing WiFi signals without connecting to any networks.

When to use:

• When assessing existing WiFi environments
• For identifying sources of interference
• When evaluating competitor or neighboring networks

Process:

• Use specialized software to scan for all WiFi signals in the area
• Identify channel utilization and potential interference
• Map existing coverage patterns

Essential Equipment for WiFi Site Surveys

To conduct an effective site survey, you'll need:

• Site survey software: Tools like Ekahau Pro, NetSpot, or AirMagnet Survey
• Survey device: Laptop or tablet with WiFi adapter (preferably similar to what end-users will use)
• Temporary access points: For active surveys
• Measuring tools: Laser distance meter, measuring tape
• Floor plans: Accurate digital or paper floor plans of the facility
• Spectrum analyzer: To identify non-WiFi sources of interference

Step-by-Step WiFi Site Survey Process

1. Pre-Survey Planning

• Gather requirements: Number of users, types of applications, security needs
• Obtain accurate floor plans with scale measurements
• Identify construction materials (concrete, drywall, glass, etc.)
• Note potential sources of interference (microwave ovens, Bluetooth devices, etc.)
• Determine coverage requirements for different areas

2. Visual Inspection

• Walk through the facility to validate floor plans
• Identify physical obstacles not shown on plans
• Note areas with high user density
• Locate available network and power outlets
• Identify mounting options for access points

3. Conduct the Survey

For a manual active survey:

• Set up temporary access points at proposed locations
• Configure them with planned SSIDs, channels, and power settings
• Walk through the facility in a grid pattern, marking your location on the floor plan
• Record signal strength, noise levels, and data rates at each point
• Test actual application performance where critical
• Adjust access point placement as needed and retest

4. Analyze Results

• Generate heat maps showing signal coverage
• Identify areas with inadequate coverage or excessive interference
• Verify that performance meets requirements throughout the coverage area
• Check for channel overlap between access points
• Ensure adequate capacity for user density

5. Document and Report

• Create detailed documentation of the final design
• Include access point locations, channels, and power settings
• Document SSID and security configurations
• Provide coverage maps and performance expectations
• Include recommendations for future expansion

Common Challenges and Solutions

High-Density Areas

Areas with many users (conference rooms, auditoriums) require special attention.

• Use more access points with lower power settings
• Implement band steering to utilize 5GHz where possible
• Consider directional antennas to focus coverage

Interference

Interference can significantly impact WiFi performance.

• Use a spectrum analyzer to identify non-WiFi interference sources
• Plan channel assignments to minimize co-channel interference
• Consider using 5GHz where possible (less crowded than 2.4GHz)
• Shield or relocate devices causing interference

Building Materials

Different materials affect WiFi signals differently.

• Concrete and metal significantly block signals
• Glass can create reflections causing multipath issues
• Plan for additional access points in areas with signal-blocking materials
• Consider wall-mounted APs for better penetration through walls

Post-Deployment Validation

After installing the WiFi network based on your survey:

• Conduct a post-installation survey to verify coverage matches expectations
• Test actual throughput and application performance
• Verify seamless roaming between access points
• Make final adjustments to channel and power settings
• Document the final "as-built" configuration

Conclusion

A thorough WiFi site survey is an investment that pays dividends in network performance and reliability. By following these guidelines, you can design and implement a wireless network that meets your organization's needs while avoiding common pitfalls.

At A1 Networking, our WiFi experts use industry-leading tools and methodologies to conduct comprehensive site surveys for businesses of all sizes. Contact us to learn how we can help optimize your wireless network performance.