FNG's Guide To Understanding Wi-fi Site Surveys

Wireless site surveys are paramount for the effective design and upkeep of wireless networks, as they ensure comprehensive coverage and optimal signal strength. Highlighting the significance, Fortitude Nicsa Global has taken the forefront in performing Ekahau Wireless Surveys across the globe, adhering to best practices in network design, including the use of cutting-edge equipment like Ekahau Sidekick 2. Skipping these vital assessments could lead to unnecessary expenditures in network infrastructure by overprovisioning access points (APs) or, conversely, enduring productivity losses due to insufficient coverage or performance issues.

Wireless site surveys, which can be categorised into predictive, passive, and active types, are not just about perfecting current networks but are crucial in planning for future expansions or new installations. They serve as a foundational tool in eliminating WiFi downtime and resolving signal dead zones, which can critically impact business operations, lead to revenue losses, and drive end-users towards competitors due to network dissatisfaction. As we embark on this comprehensive guide, we will delve into each survey type, exploring their unique methodologies and benefits, and offering insights on selecting the right wireless survey for your organisational needs.

What is a Wireless Survey?

A wireless site survey, often referred to as a WLAN site survey or RF site survey, is a meticulous process aimed at planning and optimising a wireless network within a specific location to ensure it meets the necessary coverage, data rates, network capacity, roaming capabilities, and quality of service (QoS). This type of survey involves a physical site inspection where wireless radio frequency (RF) networks are to be installed, utilising tools like Ekahau, AirMagnet, and iBwave for in-depth analysis.

Key Components of a Wireless Site Survey

1. Initial Assessment: It starts with a site visit to test for RF interference and determine the most effective locations for access points.
   
   
2. Data Collection: Various methods are used, including passive listening to WLAN traffic to identify active access points and measure signal strengths and noise levels. In contrast, active surveys involve connecting to the network to gather detailed data such as throughput rates and packet loss.
   
   
3. Analysis and Reporting: The final step is analysing the collected data to create a comprehensive report that recommends optimal placement and quantity of APs based on expected usage and environmental factors.
   
   

By conducting these surveys, organisations can achieve significant cost savings by optimising network installations and minimising the risk of expensive future modifications. Moreover, these surveys are crucial for scenarios such as office expansions, network upgrades, or troubleshooting existing issues, ensuring enhanced security, improved coverage, and a better user experience.

Passive Wireless Survey

In a passive wireless survey, the primary task involves walking through the designated site to record essential metrics such as signal strength and noise levels, all without the need to connect to the wireless network. This type of survey is crucial for initially assessing the coverage of a wireless network, allowing us to identify any potential gaps in coverage. We utilise colour-coded maps to visually represent signal strength, which helps in predicting the likely internet speeds that connected devices might experience.

However, it’s important to note that modern laptops often fall short in providing comprehensive noise data. This limitation necessitates the use of specialised tools, such as NetAlly devices, which are adept at capturing detailed signal data essential for a thorough analysis. During the survey, we passively listen to the WLAN traffic. This process enables the detection of active access points and the measurement of both signal strength and noise levels, which are critical for evaluating the wireless network’s performance.

The passive survey method is not only used before deploying a network but also periodically after installation. It provides a comprehensive report detailing all detected signals at each surveyed location. This includes signals from the installed network as well as those from neighbouring sites or other devices that might create noise at wireless frequencies. Such surveys are instrumental in pinpointing performance issues before they become evident to users, thus maintaining an optimal network operation.

Active Wireless Survey

Active wireless surveys are essential for thoroughly assessing the performance of a wireless network. Unlike passive surveys, active surveys involve direct interaction with the network by connecting to the wireless system, which allows for a detailed measurement of network performance indicators such as signal strength, throughput, and packet loss.

1. Procedure and Measurements: During an active wireless survey, the surveyor moves around the area of concern while connected to the network. This approach simulates real-world usage as the device joins and roams between different access points (APs). It measures critical data such as signal strength, throughput, round-trip time, packet loss, and retransmission rates. This method provides a clear picture of how each AP performs under actual network conditions.
   
   

2. Identifying Network Issues: One of the key advantages of active surveys is their ability to show where devices roam between APs and detect APs that are broadcasting a signal but are not allowing devices to join them. This is crucial for troubleshooting as it helps identify areas where users might experience connectivity issues.
   
   

3. Comprehensive Coverage Analysis: By collecting data up to the edge of each AP’s coverage area, active surveys help in identifying false negatives—areas that might appear to have poor Wi-Fi due to client devices not roaming effectively. This thorough data collection is performed by walking the site multiple times, ensuring that active data from each AP is accurately captured, which aids in optimising the network setup for efficient performance.
   
   

These surveys are particularly useful when investigating specific performance problems or when validating the network’s functionality during normal operational hours, ensuring that the network meets the required standards for efficient business operations.

Predictive Wireless Survey

Predictive wireless surveys utilise sophisticated software to create a virtual model of a site, which helps in planning the layout of wireless networks before actual physical deployment. These surveys are crucial when moving into new spaces or during the initial stages of network design, as they use tools and detailed blueprints to predict how signals will propagate through the environment. This method involves inputting data such as floor plans, construction materials, and the expected number of wireless users into predictive site survey software like NetSpot 3.

Key components of conducting a predictive wireless survey include:

1. Uploading and Calibrating the Map: Start by uploading a floor plan into the software and calibrate it to the actual dimensions.
   
   
2. Adding Architectural Elements: Input details about walls, windows, and other structural elements that could affect signal propagation.
   
   
3. Placing Virtual Access Points: Strategically position virtual APs within the map to simulate optimal placement and coverage.
   
   
4. Running Simulations: Perform simulations to analyse signal strength, noise levels, and other critical network performance metrics.
   
   

The results from predictive wireless surveys can offer a comprehensive heat map showing potential signal strengths and areas of interference. This allows network designers to make informed decisions about where to place actual APs to ensure efficient network coverage and performance. Although predictive surveys provide a good initial estimate, their accuracy largely depends on the quality of the input data. Therefore, it’s recommended to validate these findings with a physical survey to confirm the actual on-site performance of the network. This step is crucial to avoid potential issues that could lead to costly adjustments post-installation.

AP on a Stick Survey

In the AP on a Stick (APoS) Survey, we temporarily mount access points (APs) on poles at the intended deployment height to validate predictive network designs before full installation. This method allows us to assess the actual coverage and performance of the network in a real-world scenario, ensuring that our initial simulations align with practical outcomes. By conducting both passive and active surveys using this setup, we can gather comprehensive data on signal strength, noise levels, and network reliability.

Key Steps in Conducting an APoS Survey

1. Setup and Equipment: We begin by mounting the selected AP model on a tripod or telescoping stand, equipped with an external antenna if necessary. This setup is powered by an external battery pack to ensure mobility across the survey site.
   
   
2. Data Collection: As we move the AP around the site, we connect devices to the network to measure key performance indicators like signal strength and connectivity. This step is crucial for determining the optimal locations for AP placement in the actual deployment.
   
   
3. Analysis and Adjustments: After collecting data, we analyse the results to adjust the network design. This might involve moving APs to different locations, adjusting the transmission power to match predictive designs, or even recalibrating the entire network setup.
   
   

This meticulous approach not only saves time and resources but also significantly reduces the risk of network issues post-deployment, ensuring a robust and efficient wireless network setup from the start.

Choosing the Right Type of Wireless Survey

When selecting the appropriate type of wireless survey for your organisation, it’s crucial to understand the specific needs and environment of your network. Planning surveys, for instance, are highly beneficial as they predict wireless coverage based on the types of walls and materials used within a building. This approach is particularly effective for environments with complex architectural features that might obstruct or degrade signal strength.

Additionally, planning surveys are essential when designing a wireless network from scratch or revising existing, inefficient networks. This type of survey allows network designers to strategically place access points and optimise network performance before any physical installation begins. It’s a proactive measure that prevents costly reconfigurations down the line by ensuring the network is correctly set up from the outset.

For organisations looking to overhaul their current systems or establish new installations, understanding these survey types helps in making informed decisions that align with both current and future networking requirements.

Next Steps For Your Wireless Surveys

1. Leverage Ekahau’s Comprehensive Wi-Fi Product Suite

   • To optimise your wireless network, consider utilising the extensive range of Ekahau products including Ekahau Sidekick 2, Ekahau AI Pro, and Ekahau Survey. These tools are designed to provide detailed analytics and data crucial for effective Wi-Fi site surveys.
     
     

2. Engage with Educational Resources

   • Enhance your understanding and skills by accessing the Ekahau Resource Hub. This platform offers a wealth of materials such as webinars, white papers, and case studies that can provide deeper insights into Wi-Fi network design and troubleshooting.
     
     

3. Enroll in Ekahau University

   • For those looking to further their expertise, Ekahau University offers specialised courses like ECSE Design and ECSE Troubleshooting. These courses are tailored to equip you with advanced knowledge in Wi-Fi technology and site survey execution.
     
     

By following these steps and utilising the tools and educational resources provided by Ekahau, you can significantly improve the efficiency and coverage of your Wi-Fi networks. Or you can get in touch with the team at Fortitude Nicsa Global, We have a team of ECSE certified engineers and multiple Ekahau equipment throughout the world.

FAQs

1. What are the different types of Wi-Fi surveys? Wi-Fi surveys can be categorised into three primary types: passive, active, and predictive. A passive survey involves using a site survey tool to passively listen to WLAN traffic, identifying active access points and measuring both signal strength and noise levels.

2. How is a Wi-Fi survey conducted? To conduct a Wi-Fi survey, follow these steps:

• Scale the floor plan to size.
• Map out the areas that need coverage.
• Consider the impact of older devices and pinpoint areas for improvement.
• Assess the environment for any interference.
• Plan for future expansion and capacity needs.
• Measure and test signal strength throughout.
• Document all test results and compile a comprehensive report.
  
  

3. What are important questions to ask during a Wi-Fi survey? When conducting a Wi-Fi survey, essential questions to include are:

• What is the average number of users at this site?
• Are there any concerns regarding WAN bandwidth?
• Are there specific requirements for mounting access points due to aesthetic or environmental concerns, such as in historical buildings or areas prone to moisture or dust?
  
  

4. What are the primary goals of conducting a wireless site survey? The main objectives of performing a wireless site survey are to:

• Identify areas of RF coverage and detect any interference.
• Determine optimal locations for placing access points to ensure efficient network performance and coverage.