Axiros | Open Device & Service Management

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WiFi: 2.4 GHz vs. 5 GHz


The recent studies carried out by a number of manufacturers of WiFi devices have identified the support for 5 GHz networks as a competitive advantage. But why are such networks better than 2.4 GHz ones, in which many modern routers operate? Let's look into the matter.

The standard, known as IEEE 802.11n, was first introduced in 2009. It allowed routers to use a 5 GHz or 2.4 GHz network to transmit WiFi signals. This was done to ensure that routers run smoothly in the environment with extensive interference, since the router may be near a cordless phone or have interference from a large number of Bluetooth devices that occupied the band and emitted signals. There can be a lot of such reasons that make using a router in the old range extremely inconvenient.

In all these cases, when you use WiFi to access the Internet, there will be a significant decrease in speed. Especially during the simultaneous operation of all wireless devices. The only way out of this situation is a router with a 5 GHz range.

The fact that 5 GHz networks are less congested is not the only advantage. Internet connection is more stable and a number of outages is decreased. However, there are some disadvantages too. Due to its insignificant use at this moment, the price for access points in the 5 GHz range is higher than  for devices in 2.4 GHz networks. For many people, this is a significant drawback of this technology.

Moreover, since high-frequency radio signals in the new band are heavily affected by obstacles such as tall trees for example, a line of sight to the source will be required for smooth operation. The main disadvantage is the shorter range of the wireless network compared to the 2.4 GHz band. Plus, not all already released devices support the 5 GHz band.

Sometimes the speed can drop even in 5 GHz. But despite this, the speed in the 5 GHz band is still noticeably higher compared to 2.4 GHz. When the receiving devices are moved farther from the router, the signal level in the 5 GHz band drops significantly, but compared to the 2.4 GHz network, the average speed for subscribers remains higher.

Besides improvements in PHY (e.g. 1024-QAM) or in multiple access (OFDMA as an additional kind of multiuser, APs still share environment based on CSMA/CA), there is an important change in network planning in 802.11ax - the coloring. The coloring is an additional parameter (integer and second NAV) used to distinguish native and neighboring BSS in the same channel, which reduces the Co-channel interference (CCI).

What are the conclusions?

Contrary to skeptical views that the speed will not increase significantly in a real test environment, the research has shown that:

  • The Internet speed when connected via Wi-Fi in the 5 GHz range is much higher

  • However, the range of the 5 GHz wireless network, as expected, turned out to be much shorter

That said, we still recommend choosing routers which support both bands. Even if you don't plan to move to the 802.11ax standard and use 5 GHz right now.