Femtocell is a promising technology used primarily to enhance the signal quality of mobile devices inside buildings, where coverage is spotty or the signal is weak, or simply when you want a faster and reliable connection.
1. Introduction
Femtocells are basically low-power wireless access points that operate inside licensed frequency bands for connecting standard mobile devices with a provider's network, using a broadband connection such as the DSL or a cable connection (basically using the best Internet connection available at that point). A femtocell is therefore an indoor base station that allows you to make phone calls with your mobile cellular using the Internet service avaialble locally; it is able to do that because femtocell is a transceiver that operates on the same frequencies of mobile phones, all within a home or office. When you connect with a mobile device to a femtocell, therefore, you do not use directly the provider's mobile network, but you use the base station. The femtocell will then take care of forwarding the relevant information, via Internet, to the provider's mobile network, establishing a communication to all intents and purposes identical to that which would connecting directly to the wireless mobile network. The main difference, however, is that the base station, being provided with a broadband Internet connection, can provide a very stable, reliable, of better performance, indoor signal, resulting also in a lower power consumption. It is important to remember this concept, before enthusiastically embrace this promising technology: a femtocell is a valid and reliable device only if it is so the broadband connection it relies on. In addition to solving the problems of poor receiving inside buildings (indoor mobile communications are often the most problematic ones), femtocell technology has the advantage of offering a capacity equivalent to that obtained with a third generation (3G) network, but using lower transmission levels, thus increasing the life of mobile phone batteries.
2. Layout
At the heart of a femtocell device there is an Access Point Base Station, basically a small device installed inside a house or office with the aim of offering, in that context, better support for mobile services. A base station can manage generally 5 or more mobile devices simultaneously, thereby improving the coverage of the radio signal inside the building (Figure 1).
The main advantages of using femtocell technology are as follows:
- increase in the quality of mobile radio signal and the degree of coverage within a residential or small office;
- potential reduction in call costs. This aspect strongly depends on the fees charged by the provider who delivers the service and pricing plan that was signed between the parties. However, femtocell technology typically involves a cost reduction, both in terms of initial costs and in terms of operational management costs;
- increase in transmission capacity. More and more telecommunication companies are interested in the femtocell technology, as this allows them to give customers a capacity higher than that available with traditional networks;
- availability of new services. With femtocell technology, new services will be available to the user, mainly related to the increased available bandwidth. For example, it will facilitate the sharing of data between a phone and a home computer (basically they will share the same network);
- it represents an alternative solution for the implementation of the so-called Fixed Mobile Convergence, or simply FMC. This refers to a seamless transition for the user from wired communication devices to wireless communication devices. When this transition will become a reality, it will be possible, for example, to use a single phone to switch between a data plan (network) and a calling plan.
As it often happens with the newest technologies, the femtocell slso has some potential problem to be taken into account:
- Interference: femtocell increases the coverage for users, but may be subject to interference problems, an issue to be taken into account for those who must make such devices
- Installation: it is considered that current femtocell devices are not too easy to install for the average user. This may adversely affect the cost if the installation must be performed by qualified personnel. The regulations in some countries also require that the installation is performed only by personnel of the company providing the service
- Security & Privacy: these are two key factors that femtocell technology may have to do battle
An electronics company very active in the manufacturing of chips for femtocell applications is Picochip, a pioneer of this technology (Figure 2). Picochip produces in fact picoXcell, a low-cost System-On-Chip (SoC) for applications with femtocell technology, and used inside various models of commercial base stations.
For More Details: The femtocell technology
