The transmission medium for a digital channel can be opticalcable, digital microwave link and satellite circuit, etc.

数字信道的传输媒体可以是光缆、数字微波、卫星信道等各种手段。

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Technicians on the roof, examining a microwave link to a remote transmitter, also found a cable linking to a second alleged pirate station, that while not transmitting, contained radio equipment which officials also seized.

BBC: The pirates' view of pirate radio

ViaSat also offers design capabilities and a number of complementary products including monolithic microwave integrated circuits and modules, DVB-S2 satellite communication components, video data link systems, data acceleration and compression, and mobile satellite antenna systems.

ENGADGET: ViaSat-1 sends its first words through the stratosphere to cooing stateside relatives

With financial backing from a Dallas utility, he would build the first fiber link between McAllen and Corpus Christi: Long-distance companies wanted an alternative to their weather- plagued microwave links.

FORBES: Fiber in the sagebrush