Sub-nyquist sampling for bandwidth- and hardware-efficient mobile fronthaul with MIMO processing

A network device comprising:

• a digital signal processing (DSP) unit configured to:
• obtain a plurality of electronic signals and select a first group of signals and a second group of signals from the plurality of electronic signals;
• generate phase conjugated copies of signals in the first group of signals;
• and
• aggregate the phase conjugated copies and the second group of signals to generate an aggregated electronic signal, wherein the DSP unit aggregates the phase conjugated copies and the second group of signals into sub-bands in a frequency domain via frequency-domain multiplexing (FDM), wherein the phase conjugated copies are spectrally inverted in the frequency domain;
• a digital to analog converter (DAC) configured to convert the aggregated electronic signal into an aggregated analog signal;
• and
• at least one transmitter configured to transmit the aggregated analog signal over a fiber link.

A non-transitory computer readable medium storing computer instructions, that when executed by one or more processors, cause the one or more processors to perform the steps of:

• obtaining a plurality of electronic signals and selecting a first group of signals and a second group of signals from the plurality of electronic signals;
• generating phase conjugated copies of signals in the first group of signals;
• generating an aggregated electronic signal by aggregating the phase conjugated copies and the second group of signals into sub-bands in a frequency domain via frequency-domain multiplexing (FDM), wherein the phase conjugated copies are spectrally inverted in the frequency domain;
• converting the aggregated electronic signal to an aggregated optical signal;
• and
• transmitting the aggregated optical signal over a fiber link.