Availability
Depending on which channel you use, wireless local area networks operate on 2400-2450MHz.
Microwave ovens operate on 2450MHz.
3400/3600MHz
3400 and 3600MHz are the two bands on which 5G operates (or will operate, if you don’t already have it in your area). They are the two highest frequency mobile phone bands… at the moment!
Coverage becomes very limited at these frequencies. Even some types of glass can present a barrier to signals. This means that the number of users connected to any particular base station tends to be very limited.
This in turn means that lots more base stations are needed to provide network coverage, but because not so many people connect via any given base station it means users can get fast data. These bands are best suited to urban environments and enclosed spaces (e.g. a large hotel, a mainline railway station or a stadium).
Typically, the antennas used for 5G are different to those used for 4G.
The Bigger Picture
As I mentioned earlier, most mobile phone base stations operate on more than one frequency band. Switching between bands is seamless and can take place while a call is being made, so users don’t know which band their phone is operating on at any given moment. The base stations operate by constantly trying to balance the calls and data throughput, while the phones try to conserve battery power by maintaining communication at the lowest possible power.
As regards 5G, there’s a way around the distance/penetration limitation of 3400/3600MHz. Another frequency band will soon be coming along for 5G. It is at 700MHz, the exact allocation being 703791MHz. These frequencies (formerly
UHF TV channels 49-60) were also cleared as a result of the digital TV switchover. The coverage is roughly the same as the 800/900MHz bands. The logistical problem for the network designers is that the sites you would choose to use for 700MHz base stations are not the kind of sites you would choose to use for 3400/3600MHz.
The Future
You might think that 2G and 3G mobile services are ancient and ought to be on the way out, if not already gone, but in fact 2G is likely to be around for quite some time. This is because 2G is used for smart metering and various other activities that need a limited throughput of data but must have reliable, country-wide coverage.
The development of 6G mobile phones is already underway. If you want to know what 6G is likely to be capable of, it is useful to learn from history.
Just as when 3G was the norm, we looked forward to faster data with 4G. Now 5G is being introduced and we are looking forward to even faster data with it. Although some years away it will be the same again when 6G comes along. 1Tb (terabit) data transmission rates have been mentioned.
Remember that for faster data throughput you need more bandwidth. This in turn means operating at higher frequencies, where more bandwidth is available. Expect 6G to operate on frequencies over 4000MHz. Frequency bands around 5000MHz, 26000MHz, 40000MHz and 66000MHz have been quoted. We are talking well into the microwave part of the frequency spectrum here.
Just as is the case with 5G, using higher and higher frequencies means less and less penetration by the radio waves, so for 6G even more cells will be needed. It will be a really big infrastructure for the network providers to build.
The Bat can be ordered from the Walford Electronics Ltd website (below) using their Paypal facilities for payment. Single units cost £20 and the website will automatically add £5 for post and packing. For group event organisers wishing to order for several builders, with five or more units, please quote PWBat for a discounted price of £19 each plus the usual p&p charges. Please allow plenty of time for large orders and consult me, Tim G3PCJ, at electronics@walfords.net because the Covid virus is disrupting the supply of parts. www.walfords.net