The base transceiver station has interfaces for either a digital telephone network over cable, usually fiber, or a microwave antenna feed. Some of us in the business now use the term FTTW for fiber to wireless, since wireless depends on fiber for the communications backbone and increasingly the connection to the wireless antennas, no matter what kinds of wireless we use. Wireless is not entirely wireless. The easiest way to understand. units on towers, buildings, or light posts. All devices need to be connected to a fiber network that provides the data nits, the RRU, and Baseband Units, the BBU.
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