An optical communication system comprising a signal processing apparatus and a wireless apparatus, the signal processing apparatus and the wireless apparatus realizing functions of a base station, wherein a periodic symbol sequence comprising a cyclic prefix appended to a signal of a predetermined size to which an IFFT (Inverse Fast Fourier Transform) has been applied is transmitted between the signal processing apparatus and the wireless apparatus by means of digital RoF (Radio over Fiber) transmission, wherein the signal processing apparatus and the wireless apparatus each comprise a transmission unit and a reception unit, the symbol sequence includes different kinds of OFDM symbols having different lengths, each of the symbols constituting the symbol sequence includes a cyclic prefix, not all the symbols constituting the symbol sequence have the same length, the transmission unit comprises: a compression size determination unit that acquires symbol information relating to a starting position of the symbol sequence and lengths of the symbols that constitute the symbol sequence and that each include the cyclic prefix and determines, based on the acquired symbol information, a compression size for each of symbols that each include the cyclic prefix and that are to be compressed; and a compression unit that compresses each of the symbols that constitute the symbol sequence and that each include the cyclic prefix in accordance with the compression size determined for each of the symbols that each include the cyclic prefix, and the reception unit comprises: an expansion size determination unit that determines an expansion size for each of symbols that each include the cyclic prefix and that constitute the symbol sequence that is to be expanded;and an expansion unit that expands each of the symbols that constitute the symbol sequence and that each include the cyclic prefix in accordance with the expansion size determined for each of the symbols that each include the cyclic prefix, the compression size is the size of a frame that is a unit by which a compression process is to be performed, the length of each of the symbols that constitute the symbol sequence and that each include the cyclic prefix is a multiple of the compression size, the expansion size is the size of the frame obtained by expansion, and the expansion size for each of the symbols is equal to the compression size for each of the symbols, characterised in that the compression size determination unit determines the compression size so that the frame does not include a plurality of OFDM symbols. a compression size determination unit that acquires symbol information relating to a starting position of the symbol sequence and lengths of the symbols that constitute the symbol sequence and that each include the cyclic prefix and determines, based on the acquired symbol information, a compression size for each of symbols that each include the cyclic prefix and that are to be compressed; and a compression unit that compresses each of the symbols that constitute the symbol sequence and that each include the cyclic prefix in accordance with the compression size determined for each of the symbols that each include the cyclic prefix, and the reception unit comprises: an expansion size determination unit that determines an expansion size for each of symbols that each include the cyclic prefix and that constitute the symbol sequence that is to be expanded;and an expansion unit that expands each of the symbols that constitute the symbol sequence and that each include the cyclic prefix in accordance with the expansion size determined for each of the symbols that each include the cyclic prefix, the compression size is the size of a frame that is a unit by which a compression process is to be performed, the length of each of the symbols that constitute the symbol sequence and that each include the cyclic prefix is a multiple of the compression size, the expansion size is the size of the frame obtained by expansion, and the expansion size for each of the symbols is equal to the compression size for each of the symbols, characterised in that the compression size determination unit determines the compression size so that the frame does not include a plurality of OFDM symbols. an expansion size determination unit that determines an expansion size for each of symbols that each include the cyclic prefix and that constitute the symbol sequence that is to be expanded;and an expansion unit that expands each of the symbols that constitute the symbol sequence and that each include the cyclic prefix in accordance with the expansion size determined for each of the symbols that each include the cyclic prefix, the compression size is the size of a frame that is a unit by which a compression process is to be performed, the length of each of the symbols that constitute the symbol sequence and that each include the cyclic prefix is a multiple of the compression size, the expansion size is the size of the frame obtained by expansion, and the expansion size for each of the symbols is equal to the compression size for each of the symbols, characterised in that the compression size determination unit determines the compression size so that the frame does not include a plurality of OFDM symbols.