H04L27/26412

Systems and Methods for Shaped Single Carrier Orthogonal Frequency Division Multiplexing with Low Peak to Average Power Ratio
20230049687 · 2023-02-16 · ·

Systems and methods for shaped single carrier orthogonal frequency division multiplexing with low peak to average power ratio. The system receives an input signal and modulates the input signal to form Dirichlet kernels in a time domain to generate an offset Dirichlet kernel output time array where each Dirichlet kernel has a main lobe and a plurality of side lobes. The system modulates the input signal by receiving the input signal by an N-point time input array and transforming the N-point time input array to the frequency domain by a discrete Fourier transform to generate an N-point input frequency array. The system replicates the N-point input frequency array to generate an M-point input frequency array where M is greater than N and utilizes a filter to generate a shaped M-point output filtered frequency array by multiplying the M-point input frequency array and the filter. The system transforms the shaped M-point output filtered frequency array by an inverse discrete Fourier transform to generate an M-point offset Dirichlet kernel output time array. The system generates a cyclic prefix time array by replicating duration points of an end of the M-point offset Dirichlet kernel output time array, and appends the cyclic prefix time array to a beginning of the M-point offset Dirichlet kernel output time array to generate an M-point and duration point output time array.

Systems and methods for shaped single carrier orthogonal frequency division multiplexing with low peak to average power ratio
11563617 · 2023-01-24 · ·

System and methods for shaped single carrier orthogonal frequency division multiplexing with low peak to average power ratio are provided. The system receives an input signal and modulates the input signal to form Dirichlet kernels in a time domain to generate an offset Dirichlet kernel output time array where each Dirichlet kernel has a main lobe and a plurality of side lobes. Modulating the input signal suppresses a peak to average power ratio of the offset Dirichlet kernel output time array by reducing the plurality of side lobes of each Dirichlet kernel and respective amplitudes of the side lobes.

Secure and adaptive orthogonal division waveforms multiplexing system using channel-based transformation
11558225 · 2023-01-17 ·

Disclosed is a secure and adaptive waveforms multiplexing system in advanced-level wireless communication systems (such as 5G and beyond systems).

METHODS AND SYSTEMS FOR GENERATING A LOW PEAK-TO-AVERAGE POWER RATIO (PAPR) DATA AND REFERENCE SIGNAL

Embodiments of the present disclosure relate to systems and methods to generate a signal in a communication network. The method comprises filtering a discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-s-OFDM) data signal, and one of a DFT-S-OFDM and orthogonal frequency division multiplexing (OFDM) reference signal (RS) using a data filter and a RS filter respectively, to produce filtered data signal and filtered RS. The RS filter has one to one relationship with the data filter. Thereafter, port mapping the filtered RS to a corresponding port assigned to the transmitter to obtain port mapped filtered RS, wherein the port mapped filtered RS comprises a first subset of non-zero locations comprising of the filtered RS values and a second subset of zero locations comprising of zero values.

Context Aware Data Receiver for Communication Signals Based on Machine Learning
20230216724 · 2023-07-06 ·

A computer implemented method for detecting data (y) comprised in a part (x) of a received signal (w) of a communication system (100), wherein the received signal (w) is associated with a population and where the part (x) of the received signal (w) is associated with a sub-population of the population, the method comprising: configuring (S1) a first function (ƒ1) to determine a context (c) of the received signal (w), wherein the context (c) is indicative of a state of the received signal (w), configuring (S2) a second function (ƒ2) to detect the data (y) based on the part (x) of the received signal, wherein the second function (ƒ2) is arranged to be parameterized by the context (c), and detecting (S3) the data (y) by the first (ƒ1) and second (ƒ2) functions.

Bandwidth constrained communication systems with frequency domain information processing

The present disclosure provides techniques for bandwidth constrained communication systems with frequency domain information processing. A bandwidth constrained equalized transport (BCET) communication system can include a transmitter, a communication channel, and a receiver. The transmitter can include a pulse-shaping filter that intentionally introduces memory into a signal in the form of inter-symbol interference, an error control code (ECC) encoder, a multidimensional fast Fourier transform (FFT) processing block that processes the signal in the frequency domain, and a first interleaver. The receiver can include an information-retrieving equalizer, a deinterleaver with an ECC decoder, and a second interleaver joined in an iterative ECC decoding loop. The communication system can be bandwidth constrained, and the signal can comprise an information rate that is higher than that of a communication system without intentional introduction of the memory at the transmitter.

System and method for transmitting and receiving single-carrier OQAM symbols

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.

SIGNAL SENDING METHOD, SIGNAL RECEIVING METHOD, AND APPARATUS
20220329379 · 2022-10-13 ·

Embodiments of this application provide a signal sending method, a signal receiving method, and an apparatus, to resolve a problem that channel estimation performance is affected. A reference signal is sent on one or more consecutive symbols, and modulation data is sent on an adjacent symbol previous to the one or more consecutive symbols in time domain and an adjacent symbol next to the one or more consecutive symbols in time domain. A sum of the modulation data carried in the symbol previous to the one or more consecutive symbols and the modulation data carried in the symbol next to the one or more consecutive symbols is zero or the modulation data is the same. Therefore, after time-domain filtering, the reference signal is not interfered with by the adjacent modulation data, so that channel estimation performance can be ensured.

System and method for an adaptive frame structure with filtered OFDM

Different filtered-orthogonal frequency division multiplexing (f-OFDM) frame formats may be used to achieve the spectrum flexibility. F-OFDM waveforms are generated by applying a pulse shaping digital filter to an orthogonal frequency division multiplexed (OFDM) signal. Different frame formats may be used to carry different traffic types as well as to adapt to characteristics of the channel, transmitter, receiver, or serving cell. The different frame formats may utilize different sub-carrier (SC) spacings and/or cyclic prefix (CP) lengths. In some embodiments, the different frame formats also utilize different symbol durations and/or transmission time interval (TTI) lengths.

Dual-Polarization FBMC in Wireless Communication Systems
20220321391 · 2022-10-06 ·

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.