System and method for communication using orbital angular momentum with multiple layer overlay modulation

A communications system, comprising:

• first signal processing circuitry for processing each of a plurality of input data streams to generate a parallel pair of data streams including an in-phase stream (I) and a quadrature-phase stream (Q) for each of the plurality of input data streams, modulating a first and second parallel pair of data streams with a selected one of at least three mutually orthogonal functions at a first and second signal widths, respectively, to generate a plurality of first data sub-layers and a plurality of second data sub-layers, generating a plurality of composite data stream by overlaying the first data subs-layers with the second data sub-layers at a preconfigured overlay offset, overlapping the plurality of composite data streams by a predetermined overlap amount;
• and
• a transmitter for transmitting the plurality of overlapped composite data streams on a wavelength of a communications link;
• a receiver for receiving the optical signal over the optical communications link, the receiver further comprising:
• second signal processing circuitry for demodulating the overlapped plurality of composite data streams into the plurality of input data streams and for controlling intersymbol interference between the plurality of composite data streams responsive to the predefined modulation process used to create the first and second data sub-layers.

A communications system, comprising:

• a transmitter for transmitting a signal including a plurality of data streams over a communications link, the transmitter further comprising:
• first signal processing circuitry for processing each of a plurality of input data streams to generate a parallel pair of data streams including an in-phase stream (I) and a quadrature-phase stream (Q) for each of the plurality of input data streams, modulating a first and second parallel pair of data streams with a selected one of at least three mutually orthogonal functions at a first and second signal widths, respectively, to generate a plurality of first data sub-layers and a plurality of second data sub-layers, generating a plurality of composite data stream by overlaying the first data subs-layers with the second data sub-layers at a preconfigured overlay offset, overlapping the plurality of composite data streams by a predetermined overlap amount;
• second signal processing circuitry for placing the plurality of overlapped composite data streams on at least one of a wavelength or frequency of the communications link;
• and
• third signal processing circuitry for controlling intersymbol interference between the plurality of composite data streams responsive to the predefined modulation process used to create the first and second data sub-layers.