The Hidden Sources of Wireless Interference | 7SIGNAL | Blog

Modern wireless connections are up against plenty of obstacles. Spectrum analysis helps nail frequency issues and get your Wi-Fi back on track.

Here at 7SIGNAL, we tackle Wi-Fi issues such as structural obstructions, conflicting tech, and invasive radio signals across five major sectors: medical, higher education, enterprise, managed service providers and manufacturing and distribution centers. Across every one of those areas, each facility has a host of devices that can make reliable wireless connection an ongoing battle – but also a mission-critical necessity.

Taking hospitals as an example, there are thousands of devices already connected to Wi-Fi, with practices like BYOD only compounding the competition for bandwidth and adding radio frequency (RF) interference. Spectrum analysis is particularly valuable for hospitals but aims to reduce or remove any facility’s RF issues. The analysis will consider your operating channels, how you’ve positioned your network access points, and many other metrics and variables.

The basics of Wi-Fi projection

Wi-Fi is broadcast on either a 2.4 GHz or 5 GHz frequency, with the latter being most recent. One frequency can’t interfere with the other, but devices sharing the same band will clash. The 5 GHz band gets props for higher speed and less congestion (the 2.4 GHz band is unlicensed, meaning any manufacturer can use its frequency), but the older 2.4 GHz is still widely used for its broader area coverage and ability to better pass through solid objects.

There are some usual suspects with RF interference regardless of your band. Cellphones, microwaves, other Wi-Fi networks, video/motion-sensor cameras, and Bluetooth can all negatively affect your wireless. Sometimes these devices can coexist. Other scenarios require an overhaul of your wireless structure.

Spectrum analysis allows engineers to “see” the electromagnetic signatures of devices and locate signal disruptions. It’s much more effective than a standard Wi-Fi analysis, which only takes 802.11 devices into account.

Visualizing the wireless spectrum

Spectrum analysis will reveal these and other Wi-Fi metrics:

• Signal quality and effectiveness of channel utilization – Co-channel interference (transmissions on the same frequency in the same area) can be remedied with a configuration change. Channel overlap is a common problem since 2.4 GHz has only three non-overlapping channels.
• Background noise – This is an unavoidable factor since electromagnetic energy is part of nature and all around us. Engineers will look for background noise that exceeds this base level and may come from sources like overhead fluorescent lighting, arc welders and medical diathermy machines. If your facility is near an airport, radar can also affect your Wi-Fi.
• Spectral signature – Wi-Fi patterns are transmitted at varying bit rate speeds. Higher bit rates are more complex transmissions and are more easily disrupted by interference. RF engineers can let you know what interference levels you have or can expect based on your bit rate.
• Non-Wi-Fi interference – Coherent transmissions come from devices that intentionally emit a meaningful signal. Security systems and Bluetooth are two examples of non-Wi-Fi tech that can disrupt your network.
• Radiated noise – This is RF interference that contains no data, such as from car alarms or microwave ovens. These incoherent sources don’t deliberately transmit or compete for signal space but can cause just as many problems.

As you can see, the modern working environment is awash with potentially competitive/disruptive signal sources. Spectrum analysis is a powerful problem-solver, but too many facilities make the mistake of deploying it only after end users start filing complaints. The best interference solutions keep an ongoing watch on your wireless connection to catch problems as they begin.

The 7SIGNAL approach

Your facility’s Wi-Fi likely supports a lot of devices, and that demand, along with future interference, will only increase. Over 4 billion more devices are expected to join Wi-Fi networks next year. The 7SIGNAL Wireless Network Monitoring service performs a comprehensive and ongoing analysis of any wireless environment to root out RF interference and align your network as powerfully as possible.

Once established, our testing model continuously runs checks on Wi-Fi to keep tabs on its performance. We compare performance simultaneously with WLAN interference, and this constant analysis has no negative effect on end-user flow. Testing can be short-term (hours) or long-term (weeks) until the relevant data is gathered.

Our RF analysis has more layers than standard spectrum analysis, which is a standard that doesn’t allow for the site-specific accuracy an individual facility needs. Most analyzers operate on an interference index of 1-100 percent or on layer 1, where signals shift their signature irregularly. Neither are enough for a meaningful review. We analyze on layers 4 to 7 and work back to layer 1, which better allows us to discover how end users are being affected by interference.

Clients get a comprehensive spectral overview of what’s hampering their Wi-Fi and what can be repositioned, replaced, or removed. Our Sapphire Eye technology can troubleshoot many more factors, and our mobile capabilities let customers check in on their network from any location. Don’t let invisible variables cause you obvious problems. Connect with us and take back control of your Wi-Fi.

7SIGNAL® is a leader in enterprise Wireless Network Monitoring. The 7SIGNAL platform is a cloud-based Wireless Network Monitoring (WNM) solution that continuously troubleshoots the wireless network for performance issues – maximizing network uptime, device connectivity, and network ROI. Contact us to discover how we continuously monitor the connectivity of over 4 million global devices.