H04L27/264

Orthogonal multiple access and non-orthogonal multiple access
11343823 · 2022-05-24 · ·

A transmitter in a wireless communication network encodes data bits of a first layer to produce a set of coded symbols; spreads the coded symbols using discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-s-OFDM); and modulates the spread symbols onto a set of OFDM subcarrier frequencies to produce a discrete-time OFDM signal. Spreading is configured to map the coded symbols to a first sparse DFT-s-OFDM code space in a DFT-s-OFDM symbol, wherein the first sparse DFT-s-OFDM code space is different from a second sparse DFT-s-OFDM code space in the DFT-s-OFDM symbol, the second sparse DFT-s-OFDM code space being employed by a second layer.

Transmission device and transmission method

A transmission device including a time-domain windowing processing circuit to which a transmission symbol is input and in which the transmission symbol is multiplied by a time window. As the time window, a result of pre-convolving an arbitrary filter into an arbitrary time window is used.

DATA MODULATION AND DEVICE AND DEMODULATION DEVICE FOR THE MULTICARRIER SYSTEM
20210359888 · 2021-11-18 ·

A data modulation and device and demodulation device for the multicarrier system are provided. The data modulation method includes: performing different cyclic shifting on data sequences of L continuous symbols respectively, L≥2; and modulating the cyclically shifted data sequences by use of a waveform function, an independent variable range of the waveform function being greater than or equal to a symbol interval of the L modulated symbols. The technical solution solves the technical problems in which the related art is not compatible with a LTE system or effectively suppressing out-of-band leakage or flexibly adjusting a symbol interval to adapt to different channel environments and exhibits poor demodulation performance, thus achieving effective suppression of the out-of-band leakage, having higher compatibility with the LTE system and improving demodulation performance and flexibility of adjusting a symbol interval by simple cyclic shifting.

Methods and apparatus for communicating a single carrier waveform

Aspects of the present application provide methods and devices for time domain implementation of a single carrier waveform such as single carrier quadrature amplitude modulation (QAM) DFT-s-OFDM and single carrier Offset QAM (OQAM). A time domain implementation allows flexible symbol lengths, lower implementation complexity as a large IDFT operation is not required in the time domain and support for variable cyclic prefix (CP) length. An OQAM implementation utilizes a pre-processing step to convert a K complex QAM symbol sequence into a 2K OQAM symbol sequence and generates a sequence for transmission in the time domain as opposed to the frequency domain.

MULTI-CARRIER SIGNAL GENERATION METHOD, APPARATUS, AND SYSTEM
20210351967 · 2021-11-11 ·

Provided are a multi-carrier signal generation method, apparatus, and system. The method comprises: according to property information of a subframe, determining filter configuration information corresponding to said subframe (101); according to the filter configuration information, obtaining a multi-carrier signal of the filter bank corresponding to each of the filter configuration information (102).

TRANSMISSION DEVICE AND TRANSMISSION METHOD

A transmission device including a time-domain windowing processing circuit to which a transmission symbol is input and in which the transmission symbol is multiplied by a time window. As the time window, a result of pre-convolving an arbitrary filter into an arbitrary time window is used.

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.

METHOD FOR PROVIDING MULTI-USER SINGLE-CARRIER TRANSMISSION WITH A SMART FRAME
20230362045 · 2023-11-09 ·

The method is related to the smart frame design that contains multi-user single-carrier (SC) transmission to support 5G-and-beyond communication systems that permit enhanced mobile broadband (eMBB), massive machine-type communication (mMTC), and ultra-reliable low-latency communication (URLLC) services. The method enhances the capacity of the system in line with the filter parameters to be selected according to the user's requirements and to meet the requirements of the desired and adjacent users.

Resilient reception of navigation signals, using known self-coherence features of those signals
11444812 · 2022-09-13 ·

An apparatus and digital signal processing means are disclosed to reliably and rapidly receive and detect navigation signals, e.g., Global Navigation Satellite System (GNSS) signals, such as Global Position System (GPS) L1 legacy, L1C, and L5 signals, using combinations of spatially diverse antenna arrays, polarization-diverse antenna arrays, frequency-channelized analysis filters, and perfect-reconstruction synthesis filters, by exploiting features of those signals that are self-coherent over known framing intervals. Among other advantages, the means can reliably and rapidly identify navigation signals based on those features, improve their quality ahead of, or during, signal despreading operations, and detect and excise inadvertent or targeted electronic attack (EA) measures, e.g., navigation signal spoofers, and narrowband or wideband jamming and co-channel interference. In one aspect, the interference excision is performed in an appliqué that can be implemented without coordination with a navigation receiver.

Dynamic selection of multicarrier mode based on QoS parameters

In one aspect, a transmitter, for a first time interval, allocates first and second portions of a frequency band to first and second multicarrier modulation schemes with first and second subcarrier spacings that differ from one another. The data is transmitted to wireless devices in the first time interval using the first and second multicarrier modulation schemes in the first and second portions of the frequency band. For a second time interval, third and fourth non-overlapping portions of a frequency band are allocated to third and fourth multicarrier modulation schemes that have third and fourth subcarrier spacings that differ from one another. The third and fourth portions and/or schemes differ from the first and second portions and/or schemes. The data is transmitted in the second time interval using the third and fourth multicarrier modulation schemes in the third and fourth portions of the frequency band.