multichannel multipoint distribution system (CATV) (MMDS)

Multichannel Multipoint Distribution System (MMDS) is a fixed wireless WLL technology for connectivity in the access area, namely for broadband transmission of data and voice. Originally deployed in North America for cable TV services such as pay TV or pay-per-view, this technology was not approved for two-way communications until 1999. MMDS operates in the 2.5 GHz range in America, and 3.5 GHz internationally.

This wireless technology is ideal for SoHo( small office, home office) applications, especially when the use of cable modems is not planned or possible. The wireless connection can bridge distances of up to 50 km. It is affected by weather conditions as well as terrain and buildings.

The frequency range in America is between 2.5 GHz and 2.68 GHz and has been allocated by the Federal Communication Commission( FCC) for broadcast services. The 180 MHzband is divided into 33 6 MHz video channels, 20 of which are used for a service called Instructional Television Fixed Service (ITFS). The remaining 13 channels are allocated for Multichannel Distribution Service( MDS) and for Multichannel Multipoint Distribution Service (MMDS). The ITFS channels are to be used by government agencies and for educational purposes.

The MMDS concept provides that two-way communication can take place in all channels and that the individual channels can be dynamically combined and shared for the purpose of bandwidth increase and adjustment of bandwidth requirements ( bandwidth on demand).