Optical orthogonal frequency division multiplexing (OFDM) dynamic allocation-based passive access network system and method

The invention provides an optical orthogonal frequency division multiplexing (OFDM) dynamic allocation-based passive access network system and a method thereof. In the system, multiple carriers generated by an optical multi-carrier generating unit included in a signal sending unit are input to an OFDM generating unit and then transmitted to a link unit, and signals are subjected to polarization multiplexing, fiber channel transmission and polarization demultiplexing in the link unit; and a signal matching and receiving unit acquires radio-frequency signals carrying information by using a signal detection module, and the information required by a user is demodulated through a signal demodulation processing unit. Dynamic subcarrier allocation of optical OFDM access can be realized by adopting the method and the system, wherein the sequential watermarking detection algorithm (SWDA) adopted by the system can dynamically adjust the distribution of each subcarrier in OFDM symbols, and an optimized access network under a low-complexity frame protocol is realized.