2.4 GHz band (wider wavelength) vs. 5 GHz band (narrower wavelength)

What is the difference between 2.4 GHz and 5 GHz? The primary difference between 2.4 GHz and 5 GHz bands is the distance of signal coverage and speed that each band is capable of. 2.4 GHz has a more extended range but a lower max speed. Conversely, the 5 GHz band has less coverage ability but has higher throughput potential.

To better understand the difference between 2.4 GHz and 5 GHz WiFi, we’ll start by going over the basics of how WiFi works.

How does WiFi work?

WiFi is a radio frequency (RF) transmission that carries information from a device (typically an access point) to a receiver (a mobile device, computer, or secondary piece of network equipment) for the purposes of transferring data and connecting to the public Internet. WiFi is built on the 802.11 series of protocols devised and published by the Institute of Electrical and Electronics Engineers (IEEE), a standard currently in its sixth overall generation of advancement known as 802.11ax or “WiFi 6” (or “WiFi 6e” for the expanded version).

Because WiFi operates as an RF transmission, it follows many of the same physical and technical realities. There are limitations in speed, broadcast range, and effectiveness. While users typically don't dig into the physical realities of WiFi, network specialists and enterprises often wrestle with these aspects. 

WiFi devices broadcast on specific frequencies. A "frequency" refers to the oscillation rate of the signal or the rate at which the signal's wavelength completes a full cycle. 

All radio signals are made of "waves" of electromagnetic energy. These waves have a few specific characteristics:

  • Waves oscillate or swing between higher and lower energy states in a sinusoidal pattern. The highest energetic state of the wave is called the "amplitude" of the wave.
  • Oscillations are periodic, which means that they are regular in their oscillations. The difference between two periods of highest amplitude is called the "wavelength" of a signal.
  • Different rates of transmission are tied to wavelength, and the radio "frequency" is the number of wavelength oscillations that pass a given point within a predetermined time. The higher the frequency, the more waves that pass a given space, and the more information that can be transmitted. 

Commonly in WiFi and other computational industries like CPU production, frequency is measured in hertz (Hz), one wavelength cycle per second. Therefore, a megahertz (MHz) is a million cycles per second, and a gigahertz (GHz) is a billion cycles per second. A higher hertz rating refers specifically to higher levels of information transmission as well as higher rates of power consumption.

Following this, the growth in WiFi broadcast technologies is based on the capability of transmitting higher rates of information over radio signals.

What are the differences between 2.4 GHz and 5 GHz?

Many immediately deduce that a transmission rate of five billion cycles per second is much better than one with less than half of that capability. However, measuring effectiveness and power aren't as clear-cut. Measuring WiFi signals by gigahertz brings a few important considerations:

  • Bandwidth: The potential speed of the signal, measured in the bits per second that can travel over that signal (typically Megabits per Second or Gigabits per Second). The higher the hertz rating, the more bandwidth it can support and thus the more information it can carry.
  • Range: Conversely, the higher the frequency, the harder it is to transmit over longer distances. 

    Consider the differences between AM and FM radio. FM radio is on a higher frequency, which means that it carries more information at higher energies, which also means that it can lose energy much more quickly. On the other hand, AM uses higher amplitudes for transmitting sound information without changing frequency.

    What does this mean? FM provides better sound and less interference at a higher frequency but cannot travel long distances, especially through obstacles. Conversely, the lower-frequency AM signal sounds worse in quality but can cover a much larger range. 

    Likewise, WiFi signals follow the same logic. A higher frequency can carry more information, with the trade-off is that the signal has a hard time penetrating obstacles or reaching over comparable distances. 

Here’s a quick breakdown of how we think through the differences:

2.4 GHz vs 5 GHz Differences

What to consider when selecting between 2.4 GHz and 5 GHz

Businesses looking at selecting either 2.4 GHz or 5 GHz networks should consider the following considerations. Fortunately, most network plans and implementations will consider these factors, but deciding on which frequency to use can affect that planning. 

  • Speed: The core question is how much bandwidth to support. Both frequencies can support many users, but the 5 GHz will provide more energy for higher-speed applications like high-definition video and gaming. 
  • Range: If your business needs wide area coverage for general usage, or if there are several obstacles (concrete walls, glass, natural features, etc.) that can interrupt signals, then a lower frequency can actually sometimes provide better performance.
  • Electronics and Interference: If there are several types of electronic equipment throughout the space (like bluetooth devices, cordless phones, baby monitors, toys, and microwaves) then lower frequencies may not function as well. A 5 GHz signal might keep interference between devices and other equipment at a minimum.
  • Usable channels: With 2.4 GHz there are only three non-overlapping channels, while 5 GHz there are 24 non-overlapping channels.

Many organizations will opt to deploy dual-band equipment that can cover both frequencies. Depending on the range and coverage, devices can connect to either the 2.4 GHz or the 5 GHz network. So a device near a wireless access point can connect to 5GHz but those further out can still access the 2.4 GHz spectrum. 

Generally, we recommend that most devices should be on 5 GHz, and 2.4 GHz should be designated for the devices that don’t support 5 GHz. At Meter, we are finding that every new standard and feature is being added to 5 GHz and end devices are prioritizing 5 GHz to connect to first. While development for devices on 2.4 GHz is stagnating, there are more devices that support 5 GHz than 2.4 GHz. For example, IoT devices and printers are common devices that are still only compatible with 2.4 GHz, largely due to the cost of adding a 5 GHz capable radio.

Conclusion

When designing a network for any business, selecting entirely from 2.4 GHz or 5 GHz isn't a zero-sum proposition. Strategic use of both can guarantee that an organization has power and speed where it is needed and coverage when it can support it. Selective connectivity can keep high-performance wireless connections operating with minimal interference or connection issues. In contrast, low-demand connections for general business or public WiFi can leverage the appropriate bandwidth. 

When you become a Meter customer, Meter is the single point of contact for everything related to your network. By default, we ensure all of our customers’ networks have a dual-band set up and handle the channel planning for you to optimize for your network’s performance. Our full-stack approach combines hardware, software, and operations so that any company can seamlessly run on a reliable and modern network.

If you have any questions or feedback, please let us know — we’d love to hear from you.

Special thanks to 

 

for reviewing this post.

Appendix