Primary and hierarchical combiner for railway communication optical fiber repeater with bidirectional communication function

The invention relates to a primary and hierarchical combiner for a railway communication optical fiber repeater with a bidirectional communication function. The primary and hierarchical combiner comprises a primary combiner, a hierarchical combiner, a first bidirectional communication channel and a second bidirectional communication, the primary combiner comprises a duplexer, and a first primary second power divider and a second primary second power divider, which are connected with the duplexer respectively, the hierarchical combiner comprises a filter and a hierarchical second power divider, which are connected with each other, one end of the first bidirectional communication channel is respectively connected with the first primary second power divider, the second primary second power divider and the hierarchical second power divider, the other end of the first bidirectional communication channel is connected with a remote terminal, one end of the second bidirectional communication channel is respectively c