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Kaabi

Not many people are familiar with what bands are, but it is an important factor that must be considered when buying a phone. A phone that works on more bands is better than a phone that uses less. It is best to choose a phone that works over three or four bands, although phones that are compatible with all four bands are still rare and expensive, however they are cheaper then they once were.

Perhaps you are wondering exactly what bands are. Bands are the frequencies that phones run on, and there are different frequencies in different parts of the world. Originally, phones could only use one band (they were “uniband”), and therefore didn’t work in areas where other bands were used. As phones became more and more advanced, they became dual, tri, and quad band. Dual bands support two bands, tri three, and quad four (of course). If you travel around the world, it is necessary to have a quad band phone if you want it to work, but if you only live in the United States or Europe, a dual band or even a single band phone will do.

In GSM phones, which are almost all phones existent now, there are four frequency bands that cell phones run on:

850 megahertz (MHz)
900 MHz
1800MHz
1900MHz

The 1900MHz band is the most frequently used band in the US, while the 850 band is used in rural areas where there are no cell phone towers around. 850 MHz bands have better range than 1900MHz bands, and that’s why 850MHz bands are used in places far away from the towers. And if you’ve ever wondered why phones in Europe aren’t sold in the US, it’s because that they don’t cover the bands in the US. In Europe, the 900MHz band is predominantly used, but because it is becoming “stuffed up”, they have added another band, 1800MHz. Remember, you don’t need all these bands, if you live in the US, even just having a 1900MHz band phone with nothing else is good enough. If you don’t travel, don’t bother wasting money on a tri or quad band phone.

There are some other bands that are used, but the areas they are in are so small that they aren’t even included in many phones. There is an 800MHz band, but hardly any territory carries it. Unfortunately, 850MHz band doesn’t work in an 800MHz band area, even though they are relatively close. However the chance of encountering an 800MHz area is miniscule.

Any other device that uses radio waves runs on bands. For example, the radio, AM, runs on 530 and 1600, while FM is 88 and 108. Television is around 175 and 215, and even air traffic control has some bands, one of which is 136. Without different band frequencies, we wouldn’t be able to have all the wireless communication devices we have today.

Duggie-g

i got a motorola v3x (tri-band) but it did not work. could it be a defective phone.

Duggie-g

i live in the us virgin islands.

Cell Doc

It should work there bc US virgin islands is 1900 band. are you not getting any signal at all? try switching the network to manual

bobolito

Actually, when talking about cellular bands 800Mhz and 850Mhz are exactly the same band. It is currently the predominant band used in the US. Cingular carriers most of its network on the 800/850Mhz band, but in addition, they also have 1900Mhz running in parallel in most areas.

The FCC has allocated three bands for wireless mobiles in the US:

The first is the 800Mhz or 850Mhz band, also known as the "Cellular" band. This was where analog historically has been run on and nowadays it carries TDMA, CDMA and GSM as well depending on the area.

The second band is the 1900Mhz band, also known as the PCS band. Carriers like Sprint and T-Mobile use this band exclusively. Sprint uses it for CDMA, and T-Mobile for GSM. Cingular used to have TDMA towers running on the PCS band as well, but with the migration to GSM and after the AT&T Wireless acquisition, all TDMA services have been moved to the cellular (800/850) band except where Cingular has exclusively PCS spectrum.

The third band was recently auctioned off by the FCC and carriers like T-Mobile got a good chunk of it. This is the AWS band and it uses the 2100Mhz band for the downlink from the towers to mobiles and 1700Mhz for the uplink from mobiles to the towers. Carriers intend to run 3G services exclusively on this new band. For instance, T-Mobile plans to deploy UMTS/HSDPA there. Cingular bought some licenses in this band as well for the expansion of their UMTS/HSDPA network.

Now, the problem with the 800 vs. 850 started when the GSM Association decided that it was more technically accurate to refer to the Cellular band as 850Mhz rather than 800Mhz. Historically in the US and North America, it was known as the 800Mhz band and only analog and digital TDMA and CDMA networks were run there. GSM only existed in the 1900Mhz (PCS) band. However, when GSM expanded more agressively in the US (circa 2002), it was natural to expand GSM down to the Cellular band as well, and the GSM Association started calling it 850Mhz instead of 800Mhz even though it was the same band. The reasoning for this, is that the number 850 is technically closer to the center of the cellular band than 800 is.

The Cellular band starts at 824Mhz and ends at 894Mhz and it is divided in two blocks (A and B) to allow for two separate carriers to operate. The PCS band starts at 1850Mhz and ends at 1990Mhz and it is divided into 6 blocks (A, B, C, D, E, and F) where up to 6 carriers can operate separately. However, normally a single carrier owns more than one of those blocks.

The new AWS band that was auctioned off in 2006 runs at 1710-1755Mhz for the downlink, and at 2110-2170 for the uplink.

AWS stands for Advanced Wireless Services and there are other bands that will be auctioned off in the future. There is a portion of the 700Mhz band that will be auctioned off for AWS, probably after the transition to digital TV is complete and those airwaves are free. There's also another portion in the 2500Mhz for AWS. Sprint/Nextel owns spectrum there and they plan on using it for WiMax, which they are ironically now calling it their "4G" network.