A picocell is a small network radio element used to improve in-building cellular coverage.

Picocell radios are typically used to boost cellphone reception in office buildings and convention centers or improve network performance in dense metroplitan deployments.

Picocells have been used by carriers for many years but have lately been overshadowed by the Femtocell phenomenon. Despite similar aims, however, there are some key differences between the two technologies:

• Picocells tend to have a longer range than femtocells, which are designed to cover a user's home or small office rather than an office floor or street corner.
  
• Femtocells only support a handful of users; picocells are designed to handle up to 100 users at one time.
  
• Picocells are radios that link back to the carrier's base-station network, whereas femtocells operate as tiny independent base stations that tunnel back to carrier's network via the user's cable or DSL connection, thus offloading traffic from the mobile carrier network.
  
• Picocells are often designed to operate with several front-end radios and backhaul options. This makes sense when designing a network element to be used in a multi-carrier environment. It is overkill for a base station designed for a single-family home.

Nonetheless, there remains a gray area between the two terms, particularly as there is some confusion as to where higher-capacity "super femtocells" begin and 3G picocells end. This is largely a debate about marketing terms at present, however, since both categories of technology are only just starting to come to market.

For more on picocells, see:

• ip.access Unveils 3G Pico
• Orange Deploys Picocell
• ip.access Expands Picocells