91 results about "Orthogonal frequency code division multiplexing" patented technology

Disclosed are methods, systems, and computer-readable medium to perform operations including: generating a mapping pattern that comprises a length-4 frequency division orthogonal cover code (FD-OCC4), the mapping pattern for mapping demodulation reference signals (DMRS) in frequency to a plurality of resource elements in at least one orthogonal frequency-division multiplexing (OFDM) symbol, wherein the DMRS are associated with a plurality of DMRS ports; mapping, using the FD-OCC4, the DMRS to the plurality of resource elements in the at least one OFDM symbol; and transmitting a transmission comprising the at least one OFDM symbol.

In one aspect, a method includes receiving, in a first wireless device, a data transmission including at least one orthogonal frequency division multiplexing (OFDM) packet from a second wireless device; processing the at least one OFDM packet to recover data and providing the data to a host processor of the first wireless device; encoding, in the first wireless device, at least one decoded symbol of the at least one OFDM packet using forward error correction coding; processing the encoded at least one decoded symbol to recover at least one corresponding transmission symbol of the at least one OFDM packet; and determining a distance estimate between the first wireless device and the second wireless device based at least in part on the corresponding transmitted symbols.

The present disclosure provides a method and apparatus for transmitting and receiving signals in a wireless communication system. According to the method and apparatus, a low-power wake-up signal (LP-WUS) may be received through a first receiver, and a second receiver may be triggered based on the reception of the LP-WUS. A length L_w of an on-off keying (OOK) symbol of the LP-WUS is determined based on (i) a length N_ofdm of an orthogonal frequency division multiplexing (OFDM) symbol, (ii) a length N_cp of a cyclic prefix (CP) duration of the OFDM symbol, and (iii) a number N of OOK symbols corresponding to the length of the OFDM symbol.

Techniques pertaining to data allocation for joint data communication and sensing in mobile communications are described. An apparatus (e.g., a user equipment (UE) ) generates a plurality of orthogonal frequency-division multiplexing (OFDM) symbols carrying data. The apparatus then transmits the plurality of OFDM symbols to: (a) communicate the data; and (b) perform mono-static sensing based on the plurality of OFDM symbols. A constraint is applied to at least one OFDM symbol of the plurality of OFDM symbols.

This invention discloses a wireless sensing method, system, device, medium, and product, comprising: generating a wireless sensing frame by triggering a sensing function at a transmitting end and transmitting the wireless sensing frame to a receiving end via a data communication frame; the wireless sensing frame is a dedicated physical layer protocol data unit format, containing at least one orthogonal frequency division multiplexing (OFDM) symbol, and carrying a sensing reference signal pre-agreed upon by the transmitting and receiving ends on a predetermined proportion of available subcarriers on the OFDM symbol; and generating sensing data based on the wireless sensing frame upon receiving it at the receiving end. These technical features overcome the performance limitations of sensing algorithms.

The present application belongs to the technical field of communications and discloses a sensing processing method, a terminal, and a network-side device. The sensing processing method in embodiments of the present application comprises: a first device acquires first configuration information and first information, the first configuration information being used for configuring a sensing signal to occupy N1 subcarriers and M1 orthogonal frequency division multiplexing (OFDM) symbols, N1 being greater than or equal to N2, M1 being greater than or equal to M2, N1*M1 being greater than N2*M2, N2 being the minimum number of sensing subcarriers that meets the requirements for the resolution and maximum unambiguous measurement range of a delay, and M2 being the minimum number of sensing OFDM symbols that meets the requirements for the resolution and maximum unambiguous measurement range of Doppler; on the basis of the first information, the first device performs target transformation on a sensing signal received by the first device to obtain a target spectrum; and the first device sends first data to a second device, the first data being determined on the basis of the target spectrum.

The present application provides a communication method, an apparatus, and a system. The method comprises: acquiring a sensing signal, the sensing signal being used for sensing a target object, the sensing signal being carried on a first resource, and a time domain resource of the first resource using an orthogonal frequency division multiplexing (OFDM) symbol, a time slot, a half-subframe, a subframe, a frame, or preset time as the granularity. In this case, the granularity of the time domain resource of the first resource is consistent with the granularity of time resources in existing technologies, so that the first resource can share a time resource division system with existing technologies, thereby aligning a start position and an end position of a sensing resource with those of a communication resource.

Systems and method provide for uplink carrier aggregation (UL CA) that is configured for a User Equipment (UE), and transmissions on multiple UL carriers by one power amplifier (PA). When a base station (e.g., a gNB) indicates the UE should switch its UL waveform from Cyclic-Prefix Orthogonal Frequency Division Multiplexing (CP-OFDM) to Discrete Fourier Transform Spread OFDM (DFT-S-OFDM) for Physical Uplink Shared Channel (PUSCH) transmission in one or more UL carriers, the base station expects that the UE transmit power on a particular carrier can be increased, the carrier for which a UL coverage issue (e.g., low signal strength, signal to noise ratio, interference, etc.) is found. UL waveform switching from CP-OFDM to DFT-S-OFDM can improve the lower bound of PCMAX, namely the total UE transmit power on UL carriers of intra-band CA.

The present disclosure relates to an entity for generating a signal. The entity is configured to generate the signal by precoding a vector, the vector comprising a group of real elements and an offset. The entity is configured to obtain the group of real elements from an orthogonal frequency-division multiplexing (OFDM) signal, and the offset from the group of real elements. Further, the present disclosure relates to an entity for generating an orthogonal frequency-division multiplexing (OFDM) signal. The entity is configured to generate the OFDM signal by grouping samples of a signal in multiple groups, and postcoding each group of the multiple groups to generate postcoded samples of the signal.

A system described herein may receive a set of attributes associated with a particular User Equipment (“UE”), such as a location of the UE, Quality of Service (“QoS”) parameters, or UE power class. The system may identify a set of radio access network (“RAN”) configuration parameters based on the received set of attributes associated with the particular UE, wherein the RAN configuration parameters include radio frequency (“RF”) channel configuration parameters such as an orthogonal frequency-division multiplexing (“OFDM”) slot format. The system may provide the identified set of RAN configuration parameters to the RAN, and the RAN may utilize the RF channel configuration parameters included in the identified set of RAN configuration parameters to configure one or more channels between the RAN and the particular UE.

The application provides a long-distance high-speed target tracking method based on low-repetition-frequency OFDM radar, which comprises the following steps: step 1, in a vehicle-mounted radar, a low-repetition-frequency transmission mode is used, and an in-pulse modulation waveform adopts an orthogonal frequency division multiplexing (OFDM) signal; step 2, a carrier frequency of each transmission pulse is modulated, and the carrier frequency of each pulse randomly jumps in a preset synthetic bandwidth; step 3, a return signal of the vehicle-mounted radar is received, the return signal of each pulse is down-converted according to the transmission carrier frequency, and a pulse signal is digitally sampled at a baseband; step 4, data obtained after the digital sampling is used to calculate motion parameters of the target; and step 5, the motion parameters obtained in step 4 are used to track and locate a long-distance high-speed target.

The application discloses a kind of power equipment operating state multi-parameter acquisition method and system, belong to electric power system monitoring technical field.Method includes: sensor array acquires multiple original analog signals, integrates after being conditioned synchronous sampling, and obtains digital stream by analog-digital conversion;Using orthogonal frequency division multiplexing technology is mapped to preset subcarrier, and composite modulation signal is generated;Coupling circuit formed by high-voltage capacitor, high-frequency transformer and low-voltage capacitor is superimposed on power supply line;After receiving end separates signal, FFT demodulation and frequency division demultiplexing are carried out, and the digital signal of each sensor is recovered.The application uses power line as medium, reduces wiring and cost, is strong and flexible in expansion.

The application relates to a communication and perception integrated multi-base station cooperative anti-shielding millimeter wave waveform design method, belonging to the field of wireless communication and perception. The application realizes the method as follows: a millimeter wave orthogonal frequency division multiplexing signal model is constructed, a user communication rate model under a random shielding environment is constructed, a millimeter wave orthogonal frequency division multiplexing signal perception performance model is constructed, and a base station cooperation perception model in the random shielding environment is constructed; based on the user communication rate model under the random shielding environment, the base station cooperation perception model in the random shielding environment and performance indexes, according to optimization theory, an anti-shielding orthogonal frequency division multiplexing communication and perception integrated waveform design problem based on multi-base station cooperation is constructed; an anti-shielding random successive convex approximation algorithm is constructed, an optimization problem of the communication and perception integrated millimeter wave waveform design is solved, and thus an anti-shielding orthogonal frequency division multiplexing communication and perception integrated beamforming result based on multi-base station cooperation is obtained, and shielding robust communication and perception are realized according to the beamforming result.

This invention discloses a signal-to-interference-plus-noise ratio (SIR) estimation method, system, terminal, and storage medium for a fundamental model of a wireless channel. The method includes: acquiring the received signal set of a target communication system within an orthogonal frequency division multiplexing (OFDM) time sequence; normalizing the received signal set to obtain a target received signal set; constructing a two-dimensional histogram based on the target received signal set; extracting features from the two-dimensional histogram to obtain global statistical features; introducing a point feature network to extract features from the received signal set to obtain target local features; and estimating the SIR based on the global statistical features and the target local features to obtain the SIR estimation result. This invention, through joint modeling of the overall statistical characteristics and individual symbol features of the received signal, learns the degree of influence of interference on the distribution of received symbols and local features, thereby characterizing the degree of distortion in the wireless environment and achieving accurate estimation of the SIR at the time slot level.

This application provides a method, apparatus, device, and medium for burst frame detection of satellite orthogonal frequency division multiplexing (OFDM) signals, which can be applied to the field of signal processing technology. The method includes: sampling a received satellite OFDM signal to obtain a discrete OFDM signal; extracting multiple first data segments and multiple second data segments from the discrete OFDM signal based on a preset sampling rate, wherein the first data segments include a cycle identifier and at least one repeating sequence associated with the cycle identifier, and the second data segments include the remaining repeating sequences excluding the at least one repeating sequence and an intermediate identifier; performing inner product processing on the first data segment and the second data segment associated with any cycle identifier among the multiple cycle identifiers to obtain a similarity between the first data segment and the second data segment; and determining that the satellite OFDM signal includes at least one burst frame in response to a similarity greater than a preset similarity threshold.

The present disclosure relates generally to coding modulation techniques for use in digital communication systems such as Orthogonal Frequency Division Multiple Access (OFDMA) systems. More particularly, the present disclosure relates to methods and apparatus for multi-level encoding and decoding. Different receivers coupled to different parallel downlink channels having different channel qualities decode different received signal constellations at different levels of resolution. This allows the overall OFDMA downlink to operate at significantly higher data rates, thereby significantly improving system-level bandwidth efficiency.

This disclosure provides methods, components, devices and systems for ambient power downlink bandwidth control. Some aspects more specifically relate to generating, by a transmitting device, a spreading waveform by concatenating a sequence of symbols having a first duration, and modulating an on-off keying (OOK) waveform having a different symbol duration with the spreading waveform. In some examples, the different waveforms may have different symbol durations, and symbol boundaries for the OOK waveform and the spreading waveform may or may not align in time. The spreading waveform may include a set of concatenated orthogonal frequency division multiplexing (OFDM) symbols, Barker sequences, or the like. The OOK waveform may include zero-mean OOK signals. The access point (AP) also may apply filtering to ensure that the generated waveform satisfies a spectral mask.

The terminal includes: a control unit that determines the OCC (Orthogonal Cover Code) applied to the physical uplink shared channel modulated by DFT-s-OFDM (Discrete Fourier Transform Spread Orthogonal Frequency Division Multiplexing) or OFDM; and a transmission unit that transmits the physical uplink shared channel to the base station using the applied OCC.

Embodiments of the present disclosure relate to a method, medium and device for reducing a peak-to-average ratio of an orthogonal frequency division multiplexing system. The method comprises: receiving original data of a signal to be transmitted; generating a first carrier signal of the orthogonal frequency division multiplexing system according to the original data; generating a plurality of mutually independent second carrier signals through a generative adversarial network according to the first carrier signal; calculating peak-to-average ratios of the plurality of mutually independent second carrier signals, and selecting a second carrier signal with the smallest peak-to-average ratio for transmission; wherein the first carrier signal and the second carrier signal both carry information of the original data. The present disclosure generates a plurality of carrier signals with the same information through a generative adversarial network for calculation and comparison of peak-to-average ratios, selects a second carrier signal with the smallest peak-to-average ratio for transmission, and thus reduces the peak-to-average ratio. Since point multiplication of a frequency domain signal and a phase rotation factor and large-scale inverse fast Fourier transform operations are not required, the computational complexity is greatly reduced.

Systems and methods for frequency domain (FD) channel autocorrelation function estimation in a communication system are disclosed. An example method includes obtaining noisy frequency domain samples, y[m], from a reference signal in an Orthogonal Frequency Division Multiplexing (OFDM) communication system. The example method also includes estimating the frequency domain channel autocorrelation function Rhh[k]. Additionally, the example method includes calculating a noise-reduced channel autocorrelation function estimate at position 0, Rhh[0], by interpolating the noisy frequency domain channel autocorrelation samples Rhh[k] at positions other than 0.

The present disclosure provides PDCCH monitoring indication methods and apparatuses, a device, and a medium. A method of the present disclosure comprises: receiving a first signal sent by a base station, wherein the first signal carries indication information, and the first signal is generated on the basis of an on-off keying waveform and / or an orthogonal frequency division multiplexing waveform; and, on the basis of the indication information, determining a behavior of a terminal or, on the basis of the state of the terminal and the indication information, determining a behavior of the terminal.

Systems, apparatus, processes, and computer readable media for wireless communication are disclosed. For example, a passive network device can receive an orthogonal frequency division multiplexing (OFDM) signal from a network device. The passive network device can transmit a backscatter signal based on the OFDM signal, the backscatter signal including frequencies of the OFDM signal shifted to non-overlapping frequencies.

This application provides a communication method, apparatus, and system. The method includes: acquiring a sensing signal for sensing a target object; the sensing signal is carried on a first resource; the temporal domain resources of the first resource are granularized using Orthogonal Frequency Division Multiplexing (OFDM) symbols, time slots, half-frames, subframes, frames, or preset times. In this case, the temporal domain resources of the first resource maintain the same granularity as the temporal resources in the current technology, thereby allowing the first resource to share a time resource partitioning system with the current technology, aligning the start and end positions of the sensing resource with the communication resources.

This invention discloses an orthogonal frequency division multiplexing (OFDM) transmission method based on dirty paper coding, belonging to the field of wireless communication technology. At the transmitting end, at least two layers of frequency domain symbols to be transmitted are generated. A first-layer OFDM signal is generated from the first-layer frequency domain symbols and non-negatively clipped in the time domain to generate first-layer clipped noise. The cumulative clipped noise from the first layer to the (h-1)th (h≥2)th layer is used as interference signal to perform dirty paper coding pre-coding on the h-th layer of the frequency domain symbols to be transmitted, generating pre-coded frequency domain symbols, and then generating the h-th layer OFDM signal. The OFDM signals of each layer are superimposed and transmitted. At the receiving end, after performing a fast Fourier transform on the received signal, the received frequency domain symbols of each layer are extracted from the received frequency domain signal and decoded independently. This invention eliminates deterministic interference between layered signals through dirty paper coding pre-coding at the transmitting end, eliminating the need for serial interference cancellation at the receiving end, avoiding error propagation problems, and significantly reducing the computational complexity at the receiving end.

A method performed by a user equipment (UE) in a wireless communication system includes receiving synchronization signal / physical broadcast channel block (SSB) based on a channel bandwidth. The SSB is received in a resource region based on 240 contiguous subcarriers within four orthogonal frequency division multiplexing (OFDM) symbols. Based on the channel bandwidth being 3 MHz, the SSB is received in a resource region within the four OFDM symbols in which some of the 240 contiguous subcarriers are punctured. The resource region includes 12 resource blocks (RBs).

Methods, systems, and devices for modifying reference signal parameters to improve channel estimation in mobile communication technology are described. An example method for wireless communication includes transmitting, by a first communication node to a second communication node, a reference signal, at least one parameter of the reference signal having been modified based on a Downlink Control Information (DCI) format message or a Medium Access Control (MAC) message, and the at least one parameter comprising one or more of a number of orthogonal frequency division multiplexing (OFDM) symbols in the reference signal, a number of OFDM symbols in the reference signal in a frequency-domain range, a time-domain position of a first symbol of the reference signal, and a number of repeated transmissions of the reference signal.

Methods, systems, and apparatus for wireless communication are described. The techniques described herein relate to Frequency Division Multiplexing (FDM) of a Demodulation Reference Signal (DMRS). A User Equipment (UE) receives control signaling including configuration for uplink control messages. The UE generates uplink control messages based on the configuration and a first uplink control message format from multiple formats. The uplink control message includes a DMRS in FDM with uplink control information (UCI). The first uplink control message format is associated with a Discrete Fourier Transform Extended Orthogonal Frequency Division Multiplexing (DFT-s-OFDM) waveform and the number of four or more OFDM symbols. The UE uses the DFT-s-OFDM waveform to transmit the uplink control messages.

This invention discloses an orthogonal frequency division multiplexing (OFDM) transmission method based on dirty paper coding, belonging to the field of wireless communication technology. At the transmitting end, at least two layers of frequency domain symbols to be transmitted are generated. A first-layer OFDM signal is generated from the first-layer frequency domain symbols and non-negatively clipped in the time domain to generate first-layer clipped noise. The cumulative clipped noise from the first layer to the (h-1)th (h≥2)th layer is used as interference signal to perform dirty paper coding pre-coding on the h-th layer of the frequency domain symbols to be transmitted, generating pre-coded frequency domain symbols, and then generating the h-th layer OFDM signal. The OFDM signals of each layer are superimposed and transmitted. At the receiving end, after performing a fast Fourier transform on the received signal, the received frequency domain symbols of each layer are extracted from the received frequency domain signal and decoded independently. This invention eliminates deterministic interference between layered signals through dirty paper coding pre-coding at the transmitting end, eliminating the need for serial interference cancellation at the receiving end, avoiding error propagation problems, and significantly reducing the computational complexity at the receiving end.