By Garrett Seeley, MS, CBET
Of all the articles I have written over the past 12 months, it would be good if we looked back at the wireless standards. Just for grins, I recently checked the Wi-Fi standards to keep abreast of updates and, sure enough, a new set of hardware is due to be released with an expanded set of capabilities and features. Regardless of if someone is used to the Wi-Fi standards or not, hospitals use wireless devices every day. More devices are using wireless as the Medical Internet of Things (MIoT) gradually expands. HTM professionals have experience with Wi-Fi cards and the 2.4 GHz frequency band. However, the field keeps changing and growing.
Previous articles addressed Wi-Fi types A, B, G, N and mentioned the AC and AX standards. We covered encryption and mentioned WPA3. We even mentioned the G wireless channels. Let’s start with the first change of the new year. The terms are going to change again. Slowly, wireless is moving away from the 802.11 IEEE lettering standard and evolving to a Wi-Fi number. This is purely for marketing and to help eliminate confusion. In fact, they now refer to the 802.11G standard as Wi-Fi 3, as it was the third and most prolific of the standards. The new standard, 802.11 BE, is going to be referred to as the Wi-Fi 7 standard. It is expected to be released in 2024. I will not talk in depth about QAM, which is a mathematical way of transmitting data in a wave shift and amplitude change. Just know that QAM became able to transmit more information in fewer clock pulses as the Wi-Fi number increased. In this regard, Wi-Fi 7 is the most modern and fastest QAM option.
Wi-Fi 7 is faster but will limit newer channels because of its wider bandwidths.
With the advent of Wi-Fi 4, IEEE introduced multiple channel broadcasts, effectively using multiple channels at a time. The N wireless devices did this but took a large block out of the the 2.4 GHz channels. Functionally, there were 12 channels to Wi-Fi 3, however the channels are too close to each other and bleed together. Therefore, there are only 3 channels to use in the 2.4 GHz range. Using more than one of these channels restricts the whole band. The Wi-Fi 3 native speed was 54Mbps. Wi-Fi 4 used at least 2 of the 3 useable channels, effectively reducing the channels to 1, but giving a 6-times speed jump, up to 300Mbps. It was made for gaming and streaming videos to high-use devices. However, the channels became bogged down because of the channel width, increasing from 20 to 40 MHz. Wi-Fi 4 took up more frequencies. The FCC answer was to expand the channels to give another band; the 5 Ghz band. This allowed Wi-Fi 4 to have more than one functional range. The 5 GHz band features up to 29 single band transmissions, and up to 12 40MHz bands. A newer standard was produced, the Wi-Fi 5 or AC standard. It allows for up to 4 bands to be used together, giving a functional boost to 1800Mbps by using 80 MHz bands. However, we grew as wireless users. People in apartment buildings were all trying to have their own Wi-Fi in an environment of hundreds of access points. The Wi-Fi 6, or AX standard, tried to expand into the 6 GHz frequency range with over 50 new single channel transmissions, however it immediately absorbed them with a 160 MHz bandwidth option. The speeds were impressive, but the wider bandwidth options took the new 6 GHz bands down to a measly seven 160 MHz bands. With usage of the 5 GHz frequencies, it expanded to nine total data paths.
Wi-Fi 7, the BE standard, will expand this feature to 320 MHz, essentially locking a user into the 5 or 6 GHz bands, and offering only three options for data flow. It will be fast, over 30 Gbps, at the cost of available bands. Overall, this may hamper the usability of Wi-Fi 7, particularly in areas with multiple access points, such as public hospital areas or apartment buildings. One thing that may help Wi-Fi 7 is a Wi-Fi 6 feature often called Color. It allows for frequency sharing and is essentially a method for multiple devices sharing a channel without losing speed. In this feature, access points do not talk to all devices all the time. Rather Wi-Fi 6 and 7 access points group devices in a way that will allow for a sort of frequency sharing. Coloring a transmission adds dead spots, giving other access points time for communication. This allows multiple access points to function better together in the same area.
Wi-Fi 7 offers better beam forming, but no expansion to WPA security.
Additionally, one of the most effective means of controlling multiple transmissions in the same environment is beam forming. By using several antennas to shape a transmission, access points can steer the waves toward a specific receiving device. It was introduced in Wi-Fi 5 with the N standard and expanded with Wi-Fi 6. This feature is called Mu-MiMo, or mutli-users, multi-in and multi-out and was standardized in Wi-Fi 6. Wi-Fi 7 will expand it to UL Mu-MiMo (Uplink Mu-MiMo), which builds on the Wi-Fi 6 techniques. Another hold over from Wi-Fi 6 is the WPA3 encryption. It offers more data bits in the hashing algorithm but, to be honest, has already been countered by online hackers using embedded exploits. I wanted Wi-Fi 7 to introduce WPA4 or some new encryption that closes the exploits better than Wi-Fi 6. However, encryption is a topic best left for another article.
Only a short 4 years after the latest release of Wi-Fi 6 version E, the new Wi-Fi 7 standard, 802.11 BE, is due to be released this year. The changes look like they are going to be good. Wi-Fi 7 is going to support the new 6 GHz band natively. It will greatly increase speed but reduces the Wi-Fi 7 to only three useable wideband data streams. Keep in mind the color feature will help to keep the channel usage functionally separated. All these changes push the Wi-Fi 7 transfers data up to a theoretical 30 Gbps. In addition, the better beam shaping is supposed to support up to 10 simultaneous high-use devices.
WPA3 is going to be used as the encryption standard. All considered, the new Wi-Fi 7 standard is a speed boost in a day and age when most users are still playing with Wi-Fi 5 devices. Most hospitals would be happy to have a Wi-Fi 6 system, and now Wi-Fi 7 is on the horizon. This will prompt several hospitals and manufacturers to upgrade their new wireless designs to make the most of video capturing and streaming of new technologies, such as 3D augmented reality. The question is, are our devices ready for it?
