Digital wireless transmission system that works in the 2.2-2.4 GHz range. It requires line of sight between transmitter and receiver, which can be 30 or more miles apart. It was designed initially as a one-way service for bringing cable TV to subscribers in remote areas or in locations that are difficult to install cable. MMDS supports approximately 33 analog channels and more than 100 digital channels of TV. In late 1998, the FCC opened up the technology for two-way transmission, enabling MMDS to provide data and Internet services to subscribers.