Cellular base stations are now undergoing a design revolution. A base station was traditionally a rack of equipment inside a shelter. That design is now becoming anachronistic because it is expensive, and because the required coaxial cable running up the tower to the antennas often results in significant losses of power. The solution: “distributed base stations,” in which the RF portion (along with suitable processing and an optical interface) is placed into a weatherproof box mounted on the tower near the antennas.
“Reducing operating costs is especially important now,” notes Aditya Kaul, practice director, “so the remote radio head has become an integral part of these new distributed base stations. Remote radio heads are also very ‘smart’: almost all are software-controlled and can be configured remotely to handle a number of air interface technologies within a given air interface family.”
“Until recently remote radio heads were just considered as base station subsystems,” notes Lance Wilson, research director. “But now, especially with the advent of OFDM technologies such as LTE and WiMAX, their use has become much more important. Service providers are also upgrading their networks with remote radio heads purchased as standalone products, helping to create a market which will show high growth in both revenue and shipments.”