Abstract: A real time fiber optic matrix switch includes at least one matrix switch port and a controller card. The controller card is configured to recognize communication protocols associated with any of the Type A-H and J signals of the Naval Tactical Data System (NTDS), and to enable the communication of information between the matrix switch and interconnected peripheral devices, as well as any interconnected matrix switches. The controller card is externally programmed by a digital logic program that multiplexes data streams of received signal types to one data stream, converts the multiplexed data stream to an optical signal, transmits the optical signal, receives the transmitted optical signal, transforms the received optical signal to an electric signal, demultiplexes the electric signal, validates the demultiplexed electric signal, and acknowledges the validated demultiplexed electric signal.

Abstract: A digital communication system is disclosed which is unique in that it modulates a sinusoidal carrier with a discrete cosine segment, a zero slope level segment, and combinations thereof. The discrete cosine segments may contain different time and amplitude values. The discrete cosine segments may be combined with each other or with zero slope level segments in order to effectively modulate the sinusoidal carrier. Rather than employing the use of filters for controlling instantaneous voltage changes, the present communication system forces the bit edges of the discrete cosine segments to occur at the zero slope points of a cosine wave, where no voltage changes occur. The communication system utilizes direct digital synthesis in order to create a carrier signal which closely represents sinusoidal carrier signal. The present communication system may be used in conjunction with various conventional methods such as phase-shift keying and amplitude-shift keying.