A modulation scheme conversion device includes: a backscattering tag to which a tag signal is provided; and a tag signal forming unit for forming a tag signal. The modulation scheme conversion device multiplies a radio signal, which has been modulated in a first modulation scheme, and a tag signal, and reconfigures the multiplied signal by using a second modulation scheme, so as to backscatter the reconfigured signal, wherein the reconfiguration is performed in a physical (PHY) layer.

A system and method are provided for processing symbols for transmission. The method involves producing a single carrier offset quadrature amplitude modulation (OQAM) waveform signal from a set of K complex symbols. The method further involves pulse shaping 2K frequency domain samples of the OQAM waveform signal with J non-zero coefficients, where the J non-zero coefficients represent a frequency response of a conjugate symmetrical pulse shape, and K≤J≤2K−1. The approach has the advantage of avoiding self-interference, with the result that better BLER performance may be possible. The approach is applicable to any modulation order and also avoids bandwidth expansion. Flexibility is provided through a trade-off between PAPR vs. spectrum efficiency.

A device, method, and non-transitory computer readable medium to perform a method of blind equalization implemented by a filter bank multi-carrier with offset quadrature amplitude modulation (FBMC-OQAM) transmission system. A first matrix W is obtained by dividing a second matrix V by a receiver waveform matrix G. The second matrix V is obtained by calculating a total objective function J until the total objective function J is either constant or below a threshold error margin. The calculation of the total objective function J includes iterating calculations with a plurality of combination of a frequency bin p and a time slot q. Weights of the obtained first matrix W are applied to an equalizer. A received signal in the equalizer is processed using the applied weights. The weights of the obtained first matrix W are configured to minimize a total outage probability P.sub.out, TOTAL.

An OFDM transmitter and an OFDM receiver respectively transmit and receive N (N≥2, 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.

Conventional filter bank multi-carrier (FBMC) wireless communication systems offer superior spectral properties compared to the cyclic-prefix orthogonal frequency-division multiplexing (CP-OFDM) approach, at the cost of an inherent shortcoming in dispersive channels called intrinsic imaginary interference. In this disclosure the DP-FBMC system was disclosed. A DP-FBMC based communication system uses two orthogonal polarizations for wireless communication systems: dual-polarization FBMC (DP-FBMC). The system significantly suppresses FBMC intrinsic interference. For the disclosed DP-FBMC all the multicarrier techniques used in CP-OFDM systems for channel equalization etc., are applicable without using complex processing methods that are required for conventional FBMC. Disclosed DP-FBMC also is more robust in multipath fading channels, and also to receiver carrier frequency offset (CFO) and Timing offset (TO). In the disclosed DP-FBMC system, three different structures may be used based on different multiplexing techniques.

An OFDM transmitter and an OFDM receiver respectively transmit and receive N (N≥2, 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.

System and method embodiments are provided for a receiver for circularly convolved signals. In an embodiment, a universal decoder for a circularly convolved signal includes a first decoder configured to decode the circularly convolved signal; a second decoder configured to decode a plurality of symbol lengths signal from a first portion of the circularly convolved signal, wherein the plurality of symbol lengths signal is time aligned with the circularly convolved signal before passing through the second decoder; and an adder component configured to sum a first decoder output coming from the first decoder and a second decoder output coming from the second decoder to produce a symbol value from which a log likelihood ratio (LLR) output is obtained.

A receiver for Filter Bank Multicarrier frequency spread signals such as FBMC, FBMC/OQAM, OFDM, comprises a linear phase rotation module adapted to introduce a linear phase rotation to a received time domain signal, a discrete Fourier transform and a Finite Impulse response digital filter. The coefficients of the digital filter define a shift of the frequency response of the prototype filter of the receiver, and the coefficients of the digital filter are fixed so as to compensate the linear phase rotation introduced by the filter. The frequency shift introduced may be equal to the reciprocal of a power of two of the modulation sub carrier spacing.

Disclosed are a method and an apparatus for controlling a quadrature amplitude modulation-filter bank multi-carrier (QAM-FBMC) system. A method of controlling interference is performed by a reception apparatus of the QAM-FBMC system, wherein the reception apparatus is paired with a transmission apparatus. The method includes receiving a pre-coded data symbol; and removing residual interference caused due to a non-orthogonal filter from the pre-coded data symbol by using a decision feedback equalizer.

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.