3G Islands of Coverage
When 3G was first rolled out, the term "islands of coverage" was used. Since it wasn't possible to rollout nationwide coverage instantly, the 3G cellsites were first deployed within the areas of highest traffic and 3G service demand. Typically this meant the metropolitan areas and city centres, where the rapid return on investment made the best commercial sense.
This 3G rollout approach was called "Islands of Coverage" - a scheme where the "sea of 2G" was additionally supplemented by areas of 3G where faster data speeds were available. Over time, the islands have gotten larger, but there are still many areas in most countries which only have 2G.
4G addresses two separate problems
The initial LTE rollout approach may be somewhat different from 3G. In the US, LTE technology is being used to solve two separate issues:
- Providing high data capacity and performance in concentrated metropolitan areas
- Extending voice and data services out to previously underserved areas
This can be illustrated as a concentric ring, where the "bulls-eye" in the middle gets full LTE service and the outside ring is also addressed. Suburban areas in between are bypassed. I've termed this the "polo mint" approach to LTE network rollout after the famous torrodial-shaped sweet with the hole in the middle.
Verizon, the largest US network, acquired spectrum at the low frequency of 700MHz which is being used for LTE rollout. This frequency enables much longer range transmission and better in-building penetration - ideal for solving the two issues above.
This may be less valid in other countries where LTE is planned for deployment at higher frequencies (such as 2.3GHz or 2.6GHz). These frequencies won't provide the long range or in-building penetration that Verizon will benefit from.
What does this mean for suburban users
If you live in the suburbs you may find that LTE service doesn't appear in your area that quickly. If you are already unhappy with the 3G service inside your home, LTE won't come along to solve that issue quite so soon.
Femtocells to the rescue
Femtocells offer a quick and effective solution for suburban areas where users consume substantial amounts of wireless data service at home. By offloading such data usage, it also frees up capacity for other users who need it when outdoors.
The timeframe for femtocell deployment (whether 3G or 4G can be debated separately) is justified even more in those areas. It could be said that the rollout of femtocells matches the polo mint profile - addressing the suburban areas first.
And perhaps femtocells could come with a box of candy to sweeten the deal and further stimulate takeup.