Abstract: An orthogonal frequency division multiplexing (OFDM) transmitter is able to communicate simultaneously with a simple direct detection receiver and also with a coherent receiver. The transmitter transmits a polarization multiplexed self-coherent signal by multiplexing a carrier in the polarization state orthogonal to the polarization state of the data signal that is embodied in the sidebands. In accordance with one particular aspect of the disclosure, the direct detection receiver receiving this self-coherent signal utilizes a single polarization analyzer before the photodiode, which simplifies the receiver architecture for direct detection of a polarization multiplexed self-coherent single sideband signal.

Abstract: An optical receiver includes a detector and frame synchronizer. The detector receives an optical OFDM bit stream having a plurality of frames. Each frame has an in-phase and quadrature phase component. Each component has an OFDM symbol-bearing data payload and a synchronization header. The synchronization header includes a single synchronization pulse. The frame synchronizer detects the synchronization header on each phase component. The frame synchronizer includes first and second pairs of digital comparators for each of the in-phase and quadrature phase components. The first and second pairs of digital comparators associated with each phase component establishes different and adjustable threshold windows that is symmetric about a zero amplitude of the synchronization pulse of the respective phase component.

Abstract: An optical receiver includes a detector and frame synchronizer. The detector receives an optical OFDM bit stream having a plurality of frames. Each frame has an in-phase and quadrature phase component. Each component has an OFDM symbol-bearing data payload and a synchronization header. The synchronization header includes a single synchronization pulse. The frame synchronizer detects the synchronization header on each phase component. The frame synchronizer includes first and second pairs of digital comparators for each of the in-phase and quadrature phase components. The first and second pairs of digital comparators associated with each phase component establishes different and adjustable threshold windows that is symmetric about a zero amplitude of the synchronization pulse of the respective phase component.

Abstract: A method by an optical network unit ONU includes, for downstream transmission, using a first tunable laser for coherent detection on a sub-band basis to increase receiver sensitivity and reduce analog-to-digital conversion ADC and digital signal processor DSP requirements within the ONU, and for upstream transmission, using a second tunable laser and using an optical signal beating between the first and second tunable lasers to generate a tunable radio frequency RF signal source for upstream multi-band OFDMA signal generation thereby avoiding need for an otherwise more costly RF clock source within the ONU, enabling low-speed digital-to-analog conversion DAC operation and rendering the ONU colorless in both optical and radio frequency RF domains.

Abstract: A software-defined (SD) optical network is disclosed. An SD optical line terminal (OLT) includes a global SD controller, one or more SD OLT drivers connected to the global SD controller, and an underlying hardware component connected to each of said one or more SD OLT drivers. An SD optical network unit (ONU) includes a local SD controller, one or more SD optical network unit (ONU) drivers connected to the local SD controller, and an underlying hardware component connected to each of said one or more SD ONU drivers, wherein the local SD controller manages said one or more SD ONU drivers by issuing commands communicated to said one or more SD ONU drivers, and wherein each of said one or more SD ONU drivers implements a required function on the underlying hardware component. Other apparatuses, systems, and methods also are disclosed.

Abstract: A Wavelength Division Multiplexed Orthogonal Frequency Division Multiple Access Passive Optical Network (WDM-OFDMA-PON) includes a passive last-mile optical split terminated by optical network units (ONUs) with OFDMA transceivers; a standard single mode fiber (SSMF) link; a central office optical line terminal (CO-OLT) coupled to SSMF link and the passive last-mile optical split, wherein the CO-OLT comprises an OFDMA transceiver, burst-mode-free operation, inline optical dispersion compensation free operation, and WDM-enabled operation.

Abstract: Systems and methods are provided for network communication using wireless base stations and an optical orthogonal frequency division multiple access (OFDMA) signal generated on an optical wavelength, with the optical OFDMA signal being composed of a plurality of OFDMA subcarriers. A multi-level modulator modulates each of the plurality of OFDMA subcarriers. A single optical wavelength propagates each of the plurality of OFDMA subcarriers to different base stations; a passive optical splitter delivers the optical OFDMA signal to different base stations; and an OFDMA subcarrier de-multiplexer delivers and extracts traffic for each of the base stations in an electronic-domain, wherein the extracted traffic is remodulated in a wireless signal format. Antennas at each of the base stations transmit wireless signals, and the wireless signals are recovered and processed from the base stations.

Abstract: An optical network includes a multidimensional coder and modulator for handling multiple-in-multiple-out MIMO spatial lightpath properties and content of any specific supercarrier, a spatial mode multiplexer responsive to orthogonal frequency division multiplexing OFDM transmissions and the multidimensional coder, a spatial-spectral routing node coupled over a fiber link to the spatial mode multiplexer for performing switching granularity by a spatial mode reconnection, a multidimensional decoder and demodulator; and a spatial mode demultiplexer coupled over a fiber link to the spatial-spectral routing node and responsive to the multidimensional decoder and demodulator.

Abstract: A software-defined (SD) optical network is disclosed. An SD optical line terminal (OLT) includes a global SD controller, one or more SD OLT drivers connected to the global SD controller, and an underlying hardware component connected to each of said one or more SD OLT drivers. An SD optical network unit (ONU) includes a local SD controller, one or more SD optical network unit (ONU) drivers connected to the local SD controller, and an underlying hardware component connected to each of said one or more SD ONU drivers, wherein the local SD controller manages said one or more SD ONU drivers by issuing commands communicated to said one or more SD ONU drivers, and wherein each of said one or more SD ONU drivers implements a required function on the underlying hardware component. Other apparatuses, systems, and methods also are disclosed.

Abstract: A method of encoding for optical transmission of information includes encoding information with a generalized low-density parity-check (GLDPC) code for providing coding gains, and constructing the GLDPC code with a Reed-Muller RM code as a component code, the component code being decodable using a maximum posterior probability (MAP) decoding. In a preferred embodiment, the GLDPC code includes a codeword length of substantially 4096, an information word length of substantially 3201, a lower-bound on minimum distance of substantially greater than or equal to 16, a code rate of substantially 0.78 and the RM component code includes an order of substantially 4 and an r parameter of substantially 6.

Abstract: A method by an optical network unit ONU includes, for downstream transmission, using a first tunable laser for coherent detection on a sub-band basis to increase receiver sensitivity and reduce analog-to-digital conversion ADC and digital signal processor DSP requirements within the ONU, and for upstream transmission, using a second tunable laser and using an optical signal beating between the first and second tunable lasers to generate a tunable radio frequency RF signal source for upstream multi-band OFDMA signal generation thereby avoiding need for an otherwise more costly RF clock source within the ONU, enabling low-speed digital-to-analog conversion DAC operation and rendering the ONU colorless in both optical and radio frequency RF domains.

Abstract: A Wavelength Division Multiplexed Orthogonal Frequency Division Multiple Access Passive Optical Network (WDM-OFDMA-PON) includes a passive last-mile optical split terminated by optical network units (ONUs) with OFDMA transceivers; a standard single mode fiber (SSMF) link; a central office optical line terminal (CO-OLT) coupled to SSMF link and the passive last-mile optical split, wherein the CO-OLT comprises an OFDMA transceiver, burst-mode-free operation, inline optical dispersion compensation free operation, and WDM-enabled operation.

Abstract: An optical network component, architecture and method for a wavelength division multiplexed passive optical network includes a band coupler configured to demultiplex first and second wavelength division multiplexed content transmitted from an optical line terminal into a first band signal and a second band signal. An arrayed wavelength grating is configured to receive the first band signal and to further demultiplex the first band signal into different wavelengths to provide a plurality of wavelength signals. An optical splitter is configured to split the second band signal into sub-signals and multiplex the sub-signals with each of the wavelength signals such that the first and second wavelength division multiplexed content is provided on a single wavelength to a user.

Abstract: An optical communication system includes a bit-interleaved coded modulation (BICM) coder; and a low-density parity-check (LDPC) coder coupled to the BICM coder to generate codes used as component codes and in combination with a coherent detector.

Abstract: A method includes estimating quadrature amplitude modulated QAM symbols in an LDPC encoded OFDM signal for transmission, performing channel estimation by training sequence to determine channel coefficients in reception of the LDPC encoded OFDM signal; and obtaining channel information detection and decoding of the LDPC encoded signal.

Abstract: A passive optical network (PON) device, system and method include an optical line terminal (OLT) receiver configured to receive multiple signals at different wavelengths simultaneously and enable multiple transmitters to operate at the same time during one upstream time slot. The optical line terminal employs Orthogonal Frequency Division Multiple Access (OFDMA) to transparently support a plurality of applications and enable dynamic bandwidth allocation among these applications where the bandwidth is allocated in two dimensional frequency and time space.

Abstract: A transmitter and method include a LDPC encoder configured to encode source data, and a mapper configured to generate three coordinates in accordance with a 3D signal constellation where the coordinates include an amplitude coordinate and two phase coordinates. A laser source is modulated in accordance with each of the three coordinates to provide a transmission signal. A receiver, includes a demapper receives an input signal from three branches to demap the input signal using a three-dimensional signal constellation having three coordinates. The three branches include a direct detection branch, and two coherent detection branches such that the direct detection branch detects an amplitude coordinate of the input signal and the two coherent detection branches detect in-phase and quadrature coordinates of the input signal. A bit prediction module and at least one LDPC decoder are configured to iteratively decode bits by feeding back extrinsic LLRs to the demapper.

Abstract: A method includes estimating quadrature amplitude modulated QAM symbols in an LDPC encoded OFDM signal for transmission, performing channel estimation by training sequence to determine channel coefficients in reception of the LDPC encoded OFDM signal; and obtaining channel information detection and decoding of the LDPC encoded signal.

Abstract: A method of encoding for optical transmission of information includes encoding information with a generalized low-density parity-check (GLDPC) code for providing coding gains, and constructing the GLDPC code with a Reed-Muller RM code as a component code, the component code being decodable using a maximum posterior probability (MAP) decoding. In a preferred embodiment, the GLDPC code includes a codeword length of substantially 4096, an information word length of substantially 3201, a lower-bound on minimum distance of substantially greater than or equal to 16, a code rate of substantially 0.78 and the RM component code includes an order of substantially 4 and an r parameter of substantially 6.

Abstract: A transmitter and method include a LDPC encoder configured to encode source data, and a mapper configured to generate three coordinates in accordance with a 3D signal constellation where the coordinates include an amplitude coordinate and two phase coordinates. A laser source is modulated in accordance with each of the three coordinates to provide a transmission signal. A receiver, includes a demapper receives an input signal from three branches to demap the input signal using a three-dimensional signal constellation having three coordinates. The three branches include a direct detection branch, and two coherent detection branches such that the direct detection branch detects an amplitude coordinate of the input signal and the two coherent detection branches detect in-phase and quadrature coordinates of the input signal. A bit prediction module and at least one LDPC decoder are configured to iteratively decode bits by feeding back extrinsic LLRs to the demapper.