With the advent of new usage patterns for cell phones has arisen the need for new solutions. What is needed is the deployment of small, targeted cells. The small cells fall under several names with often overlapping and confusing definitions. This isn’t helped when marketing misapplies the terms. Small cells are classed as femtocells, picocells, microcells and sometimes metrocells.
Femtocells are the smallest and most limited in capacity. They have a range of about 10 meters and are generally restricted to a few specific phones. They are aimed at the home user and attach to his broadband connection. AT&T sells a unit they call a “microcell” but it is really a femtocell since its range is listed as 40 feet i.e. 12 meters. The AT&T unit will transfer calls out but not in. Furthermore it does not support data units such as the iPad. In practice the AT&T unit often fails to cover a single house and can interfere with phones not tied to it. What is needed is a femtocell with a range of about 50 meters that allows any cellular customer on that carrier access. This has some sticky issues attached with the biggest being that we are talking about using the home owner’s broadband service for carrying the calls. This could mean neighbors degrading the home owner’s broadband speed. Without open access, however, increasing range means increased blocking of unauthorized phones since it will interfere with the local tower. A compromise might be to limit the femtocell to a subset of channels. All of these are solvable issues. The concept is to minimize infrastructure costs while removing home cell usage from the large towers. That frees up the towers to handle traffic on main roads with home use covered by femtocells. A well designed femtocell will also insure good coverage inside the house where outside tower signal may be weak.
A picocell is larger and more capable than a femtocell with a range up to 200 meters. With this type of unit you can cover an office building. I will pick on Verizon this time. If company ABC has a corporate account with Verizon then Verizon should make a deal with the company. If company ABC provides bandwidth on the internet back to Verizon then Verizon should install picocells to cover the offices. The business wins because cell phones now work reliably inside the office building. Verizon wins because employees of company ABC have an incentive to use Verizon as their carrier since that will guarantee service while at work.
True microcells, not the AT&T marketing kind, have a range on the order of two kilometers or less. These are good for campus coverage. Several well placed microcells can cover a large business campus, a university, or a technology park. Picking on AT&T this time, imagine being able to tell all tenants of Great Tech Technology Park that going with AT&T will guarantee service while at work or in the general area of the technology park.
Another term often used is metrocell. These have a range of one hundred to several hundred meters and thus line up most closely with the definition of a picocell. They are generally feature rich cells which are designed to integrate well with the larger towers although they are often limited to a small number of users (16 to 32).
Before any of the technology mentioned above really helps there are some needed improvements. The units need to handle more users and full data and handoff functionality must be included. All of this is being worked on and there is good progress. Companies like AirWalk and Ubiquisys are equipment providers. Alcatel-Lucent has introduced lightRadio. These targeted solutions are the ones that will provide solutions for the concentrated use patterns that are developing.
The problem is less about technology than it is about broader, inclusive thinking which makes businesses and home owners partners in solving the problem. Femtocells, picocells and microcells can eliminate the problem when at home or at work. For congested roads, technology such as lightRadio offers hope. The solution in all of these cases is rarely the addition of large towers.