Wi-Fi Heatmap: Network Analysis & Coverage - A How-To Guide
Understanding Wi-Fi Heatmaps
Determining the strength and range of your Wi-Fi network can often feel like guesswork. Instead of relying on estimations, a Wi-Fi heatmap provides a visual representation of your network's coverage.
What is a Wi-Fi Heatmap?
A Wi-Fi heatmap is essentially a color-coded diagram illustrating the signal strength throughout a given area. Areas with strong signals are typically represented with warmer colors, while weaker signal areas are shown with cooler colors.
This visual tool allows you to identify areas with poor or no connectivity, enabling targeted improvements to your Wi-Fi infrastructure.
Benefits of Using a Wi-Fi Heatmap
- Identify Dead Zones: Pinpoint areas where the Wi-Fi signal is weak or nonexistent.
- Optimize Router Placement: Determine the best location for your router to maximize coverage.
- Troubleshoot Connectivity Issues: Diagnose the cause of intermittent or slow Wi-Fi connections.
- Plan Network Expansion: Effectively plan for additional access points or range extenders.
By visualizing your Wi-Fi network, you can proactively address coverage issues and ensure a reliable connection for all your devices.
Ultimately, utilizing a Wi-Fi heatmap moves you away from simply hoping for good coverage, and towards a data-driven approach to network optimization.
Understanding the Need for Wi-Fi Heatmaps
Many homes and small businesses rely on wireless networks. Determining the actual coverage provided by your Wi-Fi access point is often necessary, potentially requiring adjustments like relocation or the addition of further access points.
Manually assessing Wi-Fi signal strength, such as taking numerous readings with a smartphone, can be time-consuming and difficult to analyze effectively.
Creating a Visual Wi-Fi Coverage Map
This guide details the creation of a Wi-Fi heatmap for the first floor of an office space. The goal is to move beyond simple signal strength numbers.
Instead, we aim to generate a detailed, visually intuitive map – a heatmap – that clearly illustrates areas of strong and weak Wi-Fi signal strength.
Benefits of a Heatmap Approach
- Easy Visualization: Quickly identify areas with poor coverage.
- Informed Decisions: Determine the best placement for access points.
- Efficient Troubleshooting: Pinpoint sources of Wi-Fi interference.
A heatmap provides an immediate and accessible understanding of your network's performance, simplifying the process of optimizing your wireless network.
Essential Requirements
To follow this guide, you will require three key elements.
- A laptop running Windows (XP or a later version) equipped with Wi-Fi.
- A complimentary download of Ekahau HeatMapper software.
- (Recommended) A diagram, floor plan, or blueprint of the area you intend to map.
Numerous commercial and a limited number of free Wi-Fi heat mapping applications are available for laptops, tablets, and smartphones. We have chosen Ekahau HeatMapper due to its user-friendly interface and its position as a free version of the professional Ekahau SiteSurvey, which carries a substantial cost. For assessing smaller networks in homes or offices, HeatMapper provides significant capabilities without expense.
While a detailed blueprint isn't mandatory, creating a quick sketch of the survey area is strongly encouraged. This provides tangible reference points during the heat map development process. A simple floor plan drawn on graph paper with a ruler and pen can be created rapidly.
Alternatively, recreating your floor plan using a program like Paint is also acceptable. The key is to ensure your blueprint is approximately to scale, allowing for accurate representation.
Should you possess full-sized blueprints of your property, many office supply stores, copy centers, and print shops – such as Office Max and FedEx Office – offer blueprint scanning services for a small fee. These services can also reduce the blueprint size if needed.
Acquiring and Setting Up HeatMapper
HeatMapper is available for complimentary use; however, a simple email registration is required to obtain the software.
Ensure you provide a functional email address, as the download link will be sent directly to your inbox.
Installation Procedure
The installation process is generally uncomplicated. For systems running Vista or later, administrative permissions will be necessary during setup.
Proceed through the installation wizard by selecting "next" at each prompt.
A unique aspect of the installation involves a request to install a specialized network driver specifically for Ekahau.
Granting this permission is essential for the software to function correctly, and will finalize the installation.
Initiating the Process: Loading Your Sketch and Establishing the Map
Upon launching the application for the initial run, the screen displayed above will appear. Should you possess a map image – and utilizing one is highly recommended – select the "I have a map image" button. Alternatively, if a map is unavailable, choose the second button; a simple grid will then serve as a reference instead of a detailed map of the area.
Selecting "I have a map image" will prompt you to choose an image file. Navigate to the desired file and load it. This action will then direct you to the primary HeatMapper interface, as illustrated below.
A slender panel on the left side of the screen showcases all the Wi-Fi access points detectable by your laptop. Ignore any extraneous access points (like those from neighboring offices or residences) as these can be filtered out prior to saving the heatmap.
The central area displays your map, or grid if you opted for a map-less approach. A quick-start guide is positioned to the right. Minimize these panels by clicking the narrow vertical strips along their inner edges to maximize the HeatMap application window’s workspace.
Beginning the Heat Mapping Procedure
To commence heat mapping, physically move your laptop to a location on the map. Left-click the mouse at the approximate point where you are standing on the on-screen map. A small marker will appear, indicating your position. Advance a few feet and repeat the process, clicking again on the map to denote the new location. Continue this pattern around the perimeter of the room.
As you move and click, a trail will begin to form within the HeatMapper application, as shown in the image below.
To halt the mapping process at any time, right-click on the map. The map will instantly transition from the trail-style visualization to the heat-style representation, as depicted below.
Analyzing the Initial Heat Map
Several aspects are noteworthy on our partially completed heat map. Notice how we traced the room's perimeter and then revisited the center. This technique enhances the density of readings, providing a more comprehensive understanding of coverage at both the edges and the core of the space.
Observe the small Access Point icons. As you move and add reference points, HeatMapper displays reachable Access Points and attempts to determine their spatial locations.
Currently, based on surveying only two rooms, the geolocation of routers isn't entirely accurate. It indicates one of our APs is located outside the building and another is affixed to the front door.
However, after completing the entire map walk-through, HeatMapper accurately pinpointed the locations of the two access points within our office with remarkable precision. Refer to the red arrows on the map below.
The two Access Points are now marked on the map within approximately one foot of their actual physical positions. The remaining routers are positioned along the map's edge, aligned with the direction of their strongest signal. An exception is a phantom AP appearing above the left red arrow—this is our neighbor's Access Point, situated a mere 20 feet from the office boundary due to the compact city lots.
Examining Individual Access Point Heatmaps
Once the map walk-through is complete, clicking on any Access Point displayed on the map reveals the signal heatmap specific to that AP. Green signifies strong signal strength, while red indicates a weaker signal.
In the image above, we observe the heatmap for the leftmost AP, indicated by the red arrow. The Wi-Fi signal from this AP does not effectively penetrate the rear of the office space. A signal is still present in the upper right corner, but it is considerably weaker.
The image below displays the coverage for the second AP (highlighted by the right red arrow in the previous image):
Coverage from the second AP is notably more consistent across the office space, as expected given its central location.
Saving Your Heatmap
Before saving, exploring the heatmaps of any interfering Access Points can be insightful. By clicking on all APs within range, we discovered intriguing patterns. For instance, a neighbor’s AP signal was reflected and amplified, creating a small area of exceptionally strong Wi-Fi access in the middle of our office, despite being weak elsewhere.
When ready to save, select the AP whose signal heatmap you wish to preserve and then click the "Save Screenshot" button in the upper left corner.
It is crucial to modify the filename. The default save function uses the original map image’s filename. Avoid overwriting your blank map by renaming the file before saving.
Interpreting Your Wi-Fi Heatmap
You have successfully generated a Wi-Fi heatmap for your home or office environment. The next step involves utilizing the readily understandable information presented within the map.
Careful examination of the heatmap allows for immediate identification of areas experiencing the weakest Wi-Fi signal strength, enabling the development of a targeted improvement strategy.
Strategies for Wi-Fi Improvement
Relocating the Access Point: A straightforward solution, when feasible, is to physically move the Access Point (AP). For instance, if the west side of the AP exhibits particularly poor coverage, assess the surrounding environment.
Consider potential obstructions such as reinforced concrete walls or large metallic objects like cabinets or refrigerators positioned between the AP and the area with weak signal reception. Even a minor adjustment, like moving the AP to another corner of the room, can yield substantial improvements.
When choosing a location for the AP, prioritize elevating it from the floor and orienting the antennas vertically. This optimizes signal broadcast across the horizontal plane of the space.
Adjusting Wi-Fi Channels: If the heatmap indicates adequate coverage but unsatisfactory transmission speeds and connectivity, utilize HeatMapper to analyze the statistics of your AP and neighboring access points. These statistics are accessible in the AP list on the application’s left-hand side.
If your AP operates on Channel 6, and numerous other APs in the vicinity also utilize the same channel, switching to a less congested channel, such as 12, is highly recommended. Further information regarding Wi-Fi channel selection can be found here.
Expanding with Additional Access Points: If your building is equipped with Ethernet cabling, adding a second AP at any cable termination point can significantly extend your Wi-Fi coverage.
Employing a Wi-Fi Repeater: Many Wi-Fi routers and APs can be configured to function as repeaters. These devices receive and retransmit Wi-Fi signals, effectively amplifying the range of an existing network.
Further Resources
For comprehensive guidance on adding APs and repeaters, along with detailed network analysis and optimization techniques, explore these How-To Geek articles:
- How To Extend Your Wi-Fi Network With Simple Access Points
- How To Get a Better Wireless Signal and Reduce Wireless Network Interference
- Change Your Wi-Fi Router Channel to Optimize Your Wireless Signal
- How To Extend Your Wireless Network with Tomato-Powered Routers
- How to Boost Your Wi-Fi Network Signal and Increase Range with DD-WRT
- HTG Explains: Understanding Routers, Switches, and Network Hardware
Do you have a valuable Wi-Fi enhancement tip or technique to share? Contribute to the discussion below and exchange your expertise with other readers.