According to the present invention, an apparatus, a system and a method for transmitting a FM batch converted signal and another signal on the same optical fiber can be provided. For example, a first signal such as CATV signal may be FM converted in batch. This converted signal may then be frequency-multiplexed with a second signal such as BS/CS satellite broadcasting RF signal to transmit over optical fiber as an optical signal. The optical signal transmitted via the optical fiber is photoelectrically converted by a single photo-receiving element and is frequency-separated by a filter after passing through a preamplifier. The frequency-separated, FM batch converted signal is FM-demodulated and restored to the first signal, and the frequency-separated second signal is converted to an IF signal by a BS/CS converter. With appropriate setting of the center frequency of the FM batch converted signal, the influence by spurious interference can be minimized.