Aastra DECT EMEA, Руководство пользователя

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Using external antennas
External antennas are useful
• for rectifying radio signals, thereby achieving a greater range in one particular direction (e.g.to
provide coverage to remote ancillary buildings).
• for providing coverage to an outside area without the shell of the building obstructing the propa-
gation of the radio signals (this is achieved by mounting the base station within the building and
the antennas outside it).
There are different types of antennas, each with highly specific radio characteristics for meeting indi-
vidual coverage requirements; they are best illustrated by radiation patterns.
Radio hop of a (horizontal/vertical) directional antenna, usually suitable for remote isolated build-
ings or areas.
Radio hop of a (horizontal/vertical) omnidirectional antenna, usually suitable for a wide-ranging
area/building.
Basics