The invention relates to an automatic frequency-selecting
GSM (
Global System for Mobile Communication) digital
optical fiber repeater and a realizing method thereof. An automatic frequency-selecting DDC (Digital
Digital Control) channel is additionally arranged in a downlink of a digital frequency-selecting
repeater, all
GSM frequency points are circularly traversed through correcting a working frequency point of the automatic frequency-selecting DDC channel, then the power of each frequency point is counted by a frequency point power counting module, an
effective frequency point is selected according to the power of each frequency point by using a certain
algorithm, and the working frequency point of the frequency-selecting
repeater is configured according to the selected
effective frequency point so that the repeater normally works. The invention has the beneficial effects that: the
effective frequency point is selected by adopting a sweep frequency technology, a new frequency point can be rapidly added under the condition that the new frequency point appears, effective frequency point Delete Time is set in the original frequency point in use according to actual conditions so as to decide that the current frequency point is deleted within what duration when no new frequency point appears. The automatic frequency-selecting
GSM digital
optical fiber repeater is realized very simply and effectively, so that the difficulty and the complexity in changing the frequency points of the frequency-selecting repeater are reduced, and an important reference and realistic significance is provided for solving the technical problems in the similar design.