Multifrequency FM-SWFM data transmission using optical fiber

This paper describes the optical fiber transmission of multifrequency FM-SWFM signals on multiple data channels. Each data channel consists of 4 bits which are allocated for frequencies at 210 kHz, 520 kHz, 715 kHz, and 1.02 MHz. Data on multiple channels, modulating FM subcarriers at 2.3 MHz, 5.0 MHz, and 8.5 MHz, is grouped by mixer and FM data grouped on multiple data channels is fed to the VCO used as the SWFM modulator operating at 20 MHz before sent to the GI optical fiber. The electrical SWFM signal is converted into the optical SWFM signal by the E/O converter, the optical SWFM signal is fed from the sender to the receiver via the GI optical fiber, and the optical SWFM signal is converted into the electrical SWFM signal at the receiver. The GI optical fiber is used to send data on multiple data channels at low speed in a distance of up to 1 km. Data on three data channels was satisfactorily transferred between the sender and receiver at the same time. Temperature sensor outputs were digitized and used as data of 4 bits.