Predictive vs Passive Wireless Site Survey: When to Use Each

Technical Guide: Predictive vs Passive Wireless Site Survey: When to Use Each

A wireless site survey is the foundation of any reliable enterprise WiFi deployment. Predictive vs Passive Wireless Site Survey: When to Use Each determines whether the network will meet coverage, capacity, and roaming targets before hardware is installed — or validates that an existing deployment meets requirements. The three main survey types — predictive, passive, and active — serve different purposes and are used at different project stages.

Ekahau's toolset (AI Pro for predictive design, Sidekick 2 for RF measurement, Survey for passive/active capture, and Analyzer for packet analysis) has become the industry standard for professional WiFi site surveys. ECSE-certified engineers follow a structured methodology: requirements gathering, floor plan calibration, AP placement modelling, on-site measurement, and deliverable generation. The output — heatmaps, AP bills of material, channel plans, and coverage reports — directly feeds into procurement and deployment.

Predictive WiFi Design Methodology

Predictive design uses software modelling to simulate RF coverage and capacity before any hardware is installed. Ekahau AI Pro is the industry standard: import calibrated floor plans, define wall materials and attenuation values, place virtual APs, and run simulations for signal strength, SNR, channel overlap, and throughput estimates. The output is a validated AP placement plan with channel assignments and power levels.

Accuracy depends on correct wall attenuation values — a concrete block wall attenuates 5 GHz signals by 12–15 dB, while a glass partition may only cause 3–5 dB loss. Calibrate by measuring actual attenuation in the target building or using Ekahau's material database as a starting point. For new construction where the building doesn't exist yet, predictive design is the only option — but plan for a post-construction validation survey to fine-tune the deployment.

Passive Wireless Site Survey

A passive survey captures the RF environment without connecting to any network. The surveyor walks the target area with a measurement device (Ekahau Sidekick 2 + laptop running Ekahau Survey) while the software records signal strength (RSSI), noise floor, channel utilisation, co-channel interference, and detected APs at each location point. The result is a set of heatmaps showing the actual RF conditions across the floor.

Passive surveys are used for two purposes: pre-deployment (measuring the existing RF environment before a new WiFi installation) and post-deployment (validating that the installed network meets coverage targets). Walk paths should follow a grid pattern covering all areas including corridors, stairwells, and meeting rooms. Mark survey points every 5–7 metres for adequate resolution. The surveyor should note environmental factors — furniture, partitions, equipment — that may change over time and affect RF propagation.

Site Survey Methodology Steps

1. Requirements gathering — document coverage zones, device types, application SLAs (voice, video, data), and density per area
2. Floor plan preparation — obtain CAD/PDF floor plans, calibrate scale, mark wall materials and attenuation values
3. Predictive design — model AP placement in Ekahau AI Pro using wall types and antenna patterns; iterate until coverage and SNR targets are met
4. On-site passive survey — walk the floor with Ekahau Sidekick 2 capturing RSSI, noise, channel utilisation, and co-channel interference
5. Active survey — connect to the network and measure real throughput, packet loss, jitter, and roaming handoff times
6. Analysis and reporting — generate heatmaps, identify dead zones or interference sources, produce AP BOM and channel plan
7. Post-deployment validation — repeat passive/active survey after installation to confirm design targets are met

Site Survey Considerations for India

Indian enterprise sites — from IT parks in Bengaluru and Hyderabad to manufacturing facilities in Pune and Chennai — require surveyors who understand local construction. Thick RCC columns, metal partition frames in co-working spaces, and glass facades in modern towers all affect RF propagation differently. Multi-tenant buildings with shared risers require careful coordination for cabling and AP mounting. Pricing for professional site surveys in India typically ranges from ₹15,000 to ₹2,00,000+ depending on site size, number of floors, and deliverable scope. Factor in travel for multi-city or Tier-2 engagements.

We deliver related wireless site survey and Ekahau AI Pro across India — from network surveys and wireless site surveys to security and VAPT, managed services and cloud. For a tailored proposal or to discuss your requirements, use the contact options below.