Abstract: Currently the channel emulation is carried out by means of stationary channel realizations in order to perform the tests and validation of the new data communication schemes. However, the channel models available in the state of the art have only been efficiently used to perform channel simulation using software, leaving its efficient implementation in Hardware still unsolved. The present development details a method and apparatus for performing the channel emulation of time selective scenarios with arbitrary dispersion (channels with both isotropic and non-isotropic arrival angle distributions or channels with asymmetric and non-asymmetric power spectral densities). Likewise, the present development allows generating arbitrarily long channel realizations for channels whose statistics are non-stationary, allowing to emulate real channels.

Abstract: Currently, wideband channel simulation/emulation is carried out through channel realizations obtained from dispersion functions dictated by communication standards, in order to perform the tests and validation of the new data communication schemes. However, the channel models available in the state of the art only consider the simulation/emulation of stationary channels with separable dispersion characteristics, allowing only the treatment of unrealistic channels. The present invention describes and details a method and apparatus for performing the channel simulation/emulation in scenarios where the channel is doubly selective, i.e., selective in time and frequency, where the simulation/emulation is of an arbitrarily long duration, and for a channel that is locally non-stationary in time, not stationary in frequency and with a non-separable dispersion function.

Abstract: The invention described herein presents a system and method to overcome the distortions and affectations introduced by the highly variant channels of one or several antennas both in the transmitter and in the receiver. Unlike any existing invention that operates under the same conditions, this device uses a completely new reception technique based on the concept of virtual trajectories in which iterative calculations or solution of linear systems in operating time are not required, thus saving a considerable amount of operations. The receiver of this device manages to convert the fast variations of the channel into virtual antennas, thus achieving a considerable increase in the signal to noise-interference ratio. The resulting performance in terms of noise immunity is much better than any technique found so far and also requires a much smaller amount of calculations in the receiver.

Abstract: A modified orthogonal frequency-division multiplexing (OFDM) communication system based on virtual decomposition of the channel is proposed. The system is fully compatible with standard OFDM transmitters and maintains several blocks of standard OFDM receivers. The proposed approach achieves also incoherent reception of multicarrier signals even with a simple autocovariance DPSK detector. This novel system substantially surpasses the performance of current approaches while requiring low computational complexity. Two preferred embodiments are described; one with coherent reception using pilot signals, and the second with incoherent receiver of differentially encoded signals.

Abstract: Currently the channel emulation is carried out by means of stationary channel realizations in order to perform the tests and validation of the new data communication schemes. However, the channel models available in the state of the art have only been efficiently used to perform channel simulation using software, leaving its efficient implementation in Hardware still unsolved. The present development details a method and apparatus for performing the channel emulation of time selective scenarios with arbitrary dispersion (channels with both isotropic and non-isotropic arrival angle distributions or channels with asymmetric and non-asymmetric power spectral densities). Likewise, the present development allows generating arbitrarily long channel realizations for channels whose statistics are non-stationary, allowing to emulate real channels.

Abstract: The invention described herein presents a system and method to overcome the distortions and affectations introduced by the highly variant channels of one or several antennas both in the transmitter and in the receiver. Unlike any existing invention that operates under the same conditions, this device uses a completely new reception technique based on the concept of virtual trajectories in which iterative calculations or solution of linear systems in operating time are not required, thus saving a considerable amount of operations. The receiver of this device manages to convert the fast variations of the channel into virtual antennas, thus achieving a considerable increase in the signal to noise-interference ratio. The resulting performance in terms of noise immunity is much better than any technique found so far and also requires a much smaller amount of calculations in the receiver.

Abstract: Currently, wideband channel simulation/emulation is carried out through channel realizations obtained from dispersion functions dictated by communication standards, in order to perform the tests and validation of the new data communication schemes. However, the channel models available in the state of the art only consider the simulation/emulation of stationary channels with separable dispersion characteristics, allowing only the treatment of unrealistic channels. The present invention describes and details a method and apparatus for performing the channel simulation/emulation in scenarios where the channel is doubly selective, i.e., selective in time and frequency, where the simulation/emulation is of an arbitrarily long duration, and for a channel that is locally non-stationary in time, not stationary in frequency and with a non-separable dispersion function.

Abstract: A modified orthogonal frequency-division multiplexing (OFDM) communication system based on virtual decomposition of the channel is proposed. The system is fully compatible with standard OFDM transmitters and maintains several blocks of standard OFDM receivers. The proposed approach achieves also incoherent reception of multicarrier signals even with a simple autocovariance DPSK detector. This novel system substantially surpasses the performance of current approaches while requiring low computational complexity. Two preferred embodiments are described; one with coherent reception using pilot signals, and the second with incoherent receiver of differentially encoded signals.