Base station

Two GSM mobile phone base stations disguised as trees in Dublin, Ireland.

Base stations (or BS) are medium to high-power multi-channel two-way radios which are in a fixed location. They are typically used by low-power single-channel, two-way radios such as mobile phones, portable phones and wireless routers. When you talk on such a mobile phone, the signals from your mobile (and perhaps dozens of other people around you) are being received and sent to a nearby base station. From that base station your phone call is connected into the regular land-line phone system by the mobile phone network. In the case of a portable phone, the connection is typically direct to a land line.

Emissions issues

Close-up of a base station in Mexico City, Mexico.

Because mobile phones and their base stations are two-way radios, they produce radio-frequency (RF) radiation (that's how they communicate), and they expose people near them to RF radiation giving concerns about mobile phone radiation and health. However, because both the phones and the base stations are low power (short range), the RF radiation exposure levels from them are generally very low.

The consensus of the scientific community, both in the US and internationally, is that the power from these mobile phone base station antennas is far too low to produce health hazards as long as people are kept away from direct access to the antennas.

It is critical to be aware of the difference between antennas, the objects that produce RF radiation; and towers or masts, the structures that the antennas are placed on. It is the antennas that people need to keep their distance from, not the towers that hold the antennas.

It is also important to be aware that there are many different designs of mobile phone base stations that vary widely in their power, their characteristics, and their potential for exposing people to RF radiation.

It is well worth considering, however, that the current international exposure guidelines (INCIRP) are based largely on what is described as the thermal effects of base station emmissions. Some scientists have questioned whether there are non thermal effects from being exposed to low level RF frequencies such as are transmitted from mobile phone base stations. Such 'non-thermal' effects include how the actual frequencies interfere with the human brain and all other cells in the human body. Sources for consideration can be found here.

See also

* Base Transceiver Station
* Mobile phone
* Access point base station
* Cellular repeater
* Portable phone
* Signal strength
* Mobile phone radiation and health
* Cell site