Remote radio heads (RRHs) are components that are used to expand the reach of wireless voice and data networks. They are typically connected to networks by base station components and optical cables, and are capable of extending coverage into rural locations, improving service in urban environments, and eliminating the dead spaces commonly found in tunnels and other similar areas. A variety of different technologies can be used in a remote radio head, including universal mobile telecommunications system (UMTS), long term evolution (LTE), and worldwide interoperability for microwave access (WiMAX®). Remote radio heads typically use just one of these technologies, depending on whether they are designed to extend a voice network, data services, or both. There are also a number of different mounting options for these devices, and they are often installed on existing poles, rooftops, and even the sides of buildings.
The structure of a typical cellular network consists of a number of cells, each of which is serviced by a cellular tower that is connected to a base station. These cells form a type of distributed radio network, where transceivers in the towers send and receive information from cellular phones. The information is processed by base station servers and forwarded across the network. In order to deal with a number of coverage issues associated with traditional cellular infrastructure, a device known is the remote radio head is often used.
Infrastructures built with remote radio heads are very similar to traditional cellular infrastructures, since these devices also connect to networks by means of base station servers, though RRHs are typically easier to deploy when building out a network, or filling in dead areas. They can be mounted on existing structures, such as poles and the sides of buildings, so they can often be installed without the planning, permitting, and building costs typically associated with cell towers. It is also possible to place a remote radio head in a confined space, such as a tunnel, to extend coverage and remove dead areas that cannot be serviced by traditional cellular towers.
There are a number of different remote radio head designs, since these devices can be used with most cellular technologies. The basic components included in each device are radio frequency (RF) transceiver circuitry, and a number of different converters. Depending on the specific technology, a remote radio head may contain analog-to-digital converters, up converters, down converters, and various other components. When a cellular provider is attempting to build out a new high speed data network, the extensive use of remote radio heads can help speed up the process and improve the overall quality of service provided to the customer base.