Single-fiber bidirectional optical line system based on C-RAN system

The invention discloses a single-fiber bidirectional optical line system based on a C-RAN system, and relates to the field of mobile communication; the system at least comprises a BBU preprocessing unit, an ODN unit, a plurality of station sending ends and a plurality of RRU preprocessing units, wherein the BBU preprocessing unit is in signal connection with a BBU device pool and is used for carrying out signal transmission with the BBU device pool; the ODN unit comprises a first optical comb-shaped filter, a first filter and a second filter, wherein the first optical comb-shaped filter is used for splitting the signals into odd waves and even waves and further used for integrating and transmitting the signals to the BBU preprocessing unit; the first filter and the second filter are in signal connection with the first optical comb-shaped filter, the first filter is used for transmitting the odd waves, and the second filter is used for transmitting the even waves; and the number of thestation sending ends is a