One band, called the A band, is 1,150 MHz wide, and the other, the B band, is 150 MHz wide. The smaller B band is available to any company, but restrictions on the A band have prevented incumbent LECs and TV operators from obtaining the spectrum. Although actual LMDS service is extremely limited at this time, it is projected to become a multibillion-dollar industry within five years, with nearly every large telecom and networking vendor having some involvement today. Downstream radio channels will typically be 20 Mhz or 40 MHz wide and upstream channels 10 MHz, resulting in about 20 to 50 Mbps of downstream bandwidth and 10 Mbps of upstream bandwidth. The carriers will be able to reuse frequencies efficiently in a cellular fashion.
Satellites are anything but fixed, but the ground stations are.
Satellites were first used for intercontinental telecommunications before undersea fiber was available and for communication in remote areas, including to remote islands and ocean-going ships. By the end of 1997, more than 180 communications satellites were deployed, and today satellite systems represent a sizeable industry. A variety of new LEO systems are in development and deployment, and they will result in an estimated 1,700 additional satellites by 2005. These new satellite networks will vastly increase the types of services available for both mobile and fixed use, but even now there are many instances when a satellite connection is the best option. Connection reliability matches landline quality though there is a somewhat greater delay of about a quarter of a second for the signal to travel to and from the satellite.