digital electronic message service (wireless) (DEMS)
Digital Electronic Message Service (DEMS) is a radio technology in the microwave range.
DEMS technology is a bi-directional radio link that can transmit messages, graphics, video, and teleconferencing using high-speed communications. DEMS technology connects individual U.S. cities and centers with each other. Microwaves in the frequency range of 10.6 GHz were used as radio frequencies, later 18 GHz and from 2005 24 GHz are used as transmission frequency.