The transfer of radio frequency (RF) signal via optical fiber is widely used in distributed antenna systems. To compensate the phase variation caused by fiber length fluctuation, passive phase correction technique is proposed with obvious advantages over the traditional active phase correction method. This paper reviews the recent developments of the stable RF transfer based on passive phase correction. The operation principles of several reported schemes are presented and the performance is

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... luated and compared. Although good results have been achieved in such schemes, they can only be used for single frequency transfer. Thus, passive phase correction technique for stable transfer of wideband RF signals should be investigated in the future.