A method for transmitting data via a coaxial electrical cable includes (a) converting symbols of each input data stream of a plurality of parallel input data streams from digital form to analog form, (b) individually filtering symbols of each input data stream, (c) transforming symbols of each input data stream from a first frequency-domain to a first time-domain, to generate parallel first time-domain samples, (d) converting the first time-domain samples to a serial multi-carrier signal, and (e) injecting the multi-carrier signal onto the coaxial electrical cable.

A detector and an interference cancellation method for a spatial multiplexing filter bank multicarrier with offset quadrature amplitude modulation (SM-FBMC/OQAM) system are provided. The detector includes a decision unit, an inter-symbol feedback filtering unit and an inter-antenna feedback filtering unit. The decision unit is configured to receive a plurality of reception signals corresponding to a subchannel and a plurality of reception antennas to output a decision signal corresponding to the subchannel and a transmission antenna. The inter-symbol feedback filtering unit is configured to feed back the decision signal corresponding to the subchannel and the transmission antenna to eliminate an inter-symbol interference (ISI). The inter-antenna feedback filtering unit is configured to feed back a decision signal corresponding to the subchannel and another transmission antenna to eliminate an inter-antenna interference (IAI).

An FBMC equalization and demodulation unit and corresponding method to process an FBMC signal includes FBMC symbols, each FBMC symbol comprising data mapped over M subcarriers, oversampled by a factor K, filtered by a prototype filter and transposed in the time-domain, comprising: a frequency domain transposition unit, configured to transpose a block of P*KM samples comprising at least one FBMC symbol into frequency domain samples, where P is an integer greater than one, an equalizer unit configured to multiply the frequency domain samples by one or more coefficients computed from a propagation channel estimate, at least one circular convolution unit, configured to perform P circular convolutions between subsets of the equalized samples and a frequency domain response of a frequency shifted version of the prototype filter, and adders, to sum corresponding outputs of each of the P circular convolutions.

A method for signal modulation in a filter bank multi-carrier system is provided. A modulation method according to one embodiment of the present disclosure includes generating a plurality of different candidate transmission signals by modulating a complex symbol vector including a plurality of complex symbols in a discrete Fourier transform (DFT) spread filter bank multi-carrier (FBMC)/offset quadrature amplitude modulation (OQAM) scheme and selecting a candidate transmission signal having a lowest peak power or peak-to-average power ratio (PAPR) as a transmission signal, wherein the generating of the plurality of candidate transmission signals comprises applying a different phase offset to the complex symbol vector according to a candidate transmission signal to be generated.

A method for generating a multicarrier signal formed by a temporal succession of multicarrier symbols, implementing the following steps for generating at least one block of multicarrier symbols: coding a set of information elements delivering a set of coded elements; puncturing a first sub-set of coded elements of the set of coded elements, according to a first puncturing pattern, delivering a first sub-set of punctured coded elements; puncturing a second sub-set of coded elements of the set of coded elements, complementary to the first sub-set, according to a second puncturing pattern, delivering a second sub-set of punctured coded elements; mapping, onto at least one complex symbol, of the punctured coded elements of the first and second sub-sets of punctured coded elements; and generating the block of multicarrier symbols from said at least one complex symbol.

Embodiments of the present disclosure describe an underwater optical communication and illumination system employing laser diodes directly encoded with data, including spectrally efficient orthogonal frequency division multiplex quadrature amplitude modulation (QAM-OFDM) data. A broadband light source may be utilized to provide both illumination to an underwater field of interest and underwater optical communication from the field of interest to a remote location.

A method for transmitting data via a coaxial electrical cable includes (a) converting symbols of each input data stream of a plurality of parallel input data streams from digital form to analog form, (b) individually filtering symbols of each input data stream, (c) transforming symbols of each input data stream from a first frequency-domain to a first time-domain, to generate parallel first time-domain samples, (d) converting the first time-domain samples to a serial multi-carrier signal, and (e) injecting the multi-carrier signal onto the coaxial electrical cable.

Embodiments of the present disclosure describe an underwater optical communication and illumination system employing laser diodes directly encoded with data, including spectrally efficient orthogonal frequency division multiplex quadrature amplitude modulation (QAM-OFDM) data. A broadband light source may be utilized to provide both illumination to an underwater field of interest and underwater optical communication from the field of interest to a remote location.

Transmitting apparatus and receiving apparatus for communication systems using coded orthogonal frequency-division multiplexed (COFDM) dual-subcarrier modulation (DCM) signals. The same coded data is mapped both to COFDM subcarriers located in the lower-frequency half spectrum of the DCM signal and to COFDM subcarriers located in its upper-frequency half spectrum. The mapping of COFDM subcarriers in those half spectra employ labeling diversity preferred for reception of DCM with less error when accompanied by interfering additive white Gaussian noise (AWGN). In preferred forms of COFDM DCM signal, the quadrature amplitude modulation (QAM) of COFDM subcarriers is Gray mapped to position palindromic lattice-point labels along one of the diagonals of each square QAM constellation.

An OFDM transmitter and an OFDM receiver respectively transmit and receive N (N2, N is an integer) control symbols. For each control symbol, a guard interval time-domain signal is, for example, identical to a signal obtained by frequency-shifting at least a portion of a useful symbol time-domain signal by an amount different from any other symbol, or to a signal obtained by frequency-shifting one or both of a portion and a span of a useful symbol interval time-domain signal different from any other symbol by a predetermined amount.