If you’ve ever had Wi-Fi deployed as part of your enterprise infrastructure, chances are a comprehensive site survey was conducted to validate coverage.  If such an assessment hasn’t been undertaken, I strongly recommend considering it.  Assuming you have completed one, it’s likely you were furnished with a detailed report presenting the findings. This report typically encapsulates an overview of your facility, accompanied by received signal strength (RSSI) indicators. It wouldn’t be surprising if the report showcased predominantly ‘green’ signals, especially if the individual presenting it was also the architect of the initial Wi-Fi design. Observing these favorable results may have instilled confidence that the investment in the state-of-the-art WLAN was indeed money well spent. However, let’s delve deeper into the nuances of the ‘green’ spectrum and its true implications.

To a discerning eye, the prevalence of ‘green’ in the signal strength indicators (RSSI) merely reveals a fraction of the overall narrative. However, it’s crucial to acknowledge that this abundance of apparently positive signals doesn’t inherently translate to optimal performance. Surprisingly, these seemingly favorable colors may be the very reason your Wi-Fi isn’t meeting your anticipated standards. How does this apparent contradiction come to be?

1. Elevating the transmit power of Access Points (APs) is a straightforward approach to bolstering coverage strength. However, it’s akin to a conversation in a quiet room where someone is excessively loud. While their words may be clear, the approach is far from ideal. In the realm of Wi-Fi, this tactic introduces various detrimental effects, including heightened interference and challenges associated with the near/far problem.
2. Overcrowding with an excess of Access Points (APs) is a common occurrence in many environments. APs seem to proliferate indiscriminately, driven by the notion that more APs equate to increased capacity. Sometimes, technicians, in an attempt to be thorough, overengineer the solution, opting for abundance rather than precision. This scenario is reminiscent of the chaotic scene in Back to the Future 2, where Michael J Fox attempts to watch 12 channels simultaneously on a big screen television. The analogy holds true for Wi-Fi— an excess of APs might display abundant ‘green’ in assessments, but for end-user devices, it translates into a cacophony of competing stations, resembling unwanted noise rather than a reliable connection.
3. While Received Signal Strength Indicator (RSSI) is a commonly referenced metric for Wi-Fi assessments, it only tells a piece of the story, especially when you consider the importance of Signal-to-Noise Ratio (SNR). SNR serves as a comprehensive measure, evaluating the signal strength against the backdrop of environmental noise, provided the survey radio can detect such noise. This ambient interference can emanate from various sources, including neighboring APs, client devices within your network, or external non-Wi-Fi interferences like microwaves, video cameras, and Bluetooth devices. Standard Wi-Fi site survey tools suffice for identifying the first two types of noise, but detecting and mitigating non-Wi-Fi interferers necessitate specialized spectrum analysis tools. Embracing a holistic approach is paramount, and SNR emerges as a more reliable indicator, particularly when gauging performance across diverse client types that require support.
4. Deploying high-powered Access Points (APs) may not align with the optimal user experience for your end-users. The landscape of Wi-Fi has evolved significantly, marked by changing requirements, expectations, and technologies. An RF design that was deemed acceptable a few years ago might fall short of meeting the demands posed by modern devices and applications. In light of these transformations, there arises a necessity for a paradigm shift in design philosophy. Rather than adhering to the conventional approach of APs transmitting at maximum signal strength, a more strategic approach involves calibrating power levels to match those of client devices. This, coupled with a meticulous focus on precise channel allocation for your specific environment, serves to maximize the utilization of the RF spectrum.
5. Making adjustments to influence the outcome of a site survey is a possibility, although ethical considerations prevent me from endorsing such practices. Familiarity with survey tools can make it relatively easy to alter parameters such as the collected data, collection methods, and signal filtering, as well as adjusting thresholds. These alterations can create an overly optimistic, ‘green’ portrayal that deviates from reality. Another concern is the inadvertent misrepresentation of results by a site survey amateur with less experience. If uncertainty exists about the accuracy of a received report, seeking a second opinion is advisable. Engaging with the engineer to discuss their findings in detail not only ensures transparency but also taps into the enthusiasm that wireless engineers typically have for discussing the intricacies of Wi-Fi.

And we’d love to talk to you about your wireless network and how TPK can help ensure that it is optimized for your needs and users.  As Wi-Fi evolves into a critical component of your business infrastructure, it becomes imperative to address the often-overlooked or unseen intricacies of your environment. Our commitment is to remove the ‘green veil’ of simplistic assessments, providing you with a transparent and strategic approach to ensure your wireless network aligns seamlessly with the demands of your business operations.”