Patent classifications
H04L25/03821
Flexible and Scalable Air Interface for Mobile Communication
A flexible time-frequency grid is proposed. A baseline OFDM format consisting of CP and a following symbol interval is scaled in time to generate a set of extended OFDM frame formats. The set of extended OFDM frame formats is further extended by scaling in bandwidth. The OFDM frame formats and the extended OFDM frame format set are used dynamically in the wireless communication system in accordance to the changes of the communication environment. Furthermore, various methods are proposed to avoid and/or combat performance degradation of the resource elements (REs) interfered by non-orthogonal REs in the neighborhood due to different OFDM symbol configurations in the flexible time-frequency grid.
Receiver apparatus and frequency selectivity interference correction method
An OFDM receiver apparatus (100) receives a signal that includes an STF having a plurality of pilot subcarriers and a plurality of null subcarriers that are alternately arranged at predetermined frequency intervals in a transmission band and that includes a data part that is time-multiplexed with the STF. A null carrier extraction unit (151) extracts a plurality of null subcarrier frequency signals from the received signal. A power calculation unit (152) detects, based on the levels of the extracted signals, the interference levels of the plurality of subcarriers in the transmission band. A soft decision unit (112) uses the reliability of the plurality of subcarriers, which is calculated based on the detected interference levels, to perform a soft decision of a demodulated signal of the received data part. An error correction unit (113) performs, based on the result of the soft decision, an error correction, thereby reconstructing the data.
Devices and methods for processing one or more received radio signals
A method for processing one or more received radio signals is provided. The method may include performing a channel estimation of a transmission channel for at least a portion of the one or more radio signals received, to identify at least one soft channel parameter representing a channel impulse response of the transmission channel, and identifying at least one soft intercarrier interference parameter representing an interference for the one or more radio signals received using a first frequency carrier. The interference is caused by the one or more radio signals received using a second frequency carrier. The method may further include detecting soft data from the one or more radio signals based at least on the at least one soft channel parameter and the at least one soft intercarrier interference parameter.
RADIO BASE STATION, USER TERMINAL AND RADIO COMMUNICATION METHOD
A radio base station that communicates with a user terminal, and has a control section that executes control so that signals are time-division-multiplexed over a first radio resource region where symbols are multiplexed at a rate equal to or below a Nyquist rate and a second radio resource region where symbols are multiplexed at a faster rate than the Nyquist rate. The radio base station also includes a transmission section that transmits the signals that are time-division-multiplexed in the first radio resource region and the second radio resource region, to the user terminal to reduce the interference against predetermined signals in a radio communication system in which Faster-Than-Nyquist (FTN) is used.
Method for determining impulsive interference applicable to orthogonal frequency division multiple access signal receiver and receiver thereof
A method for determining impulsive interference applicable to an orthogonal frequency division multiple access (OFDMA) signal receiver is provided. The receiving method includes calculating a subcarrier noise of a first symbol, calculating a subcarrier noise of a second symbol, calculating a first ratio of the subcarrier noise of the first symbol to the subcarrier noise of the second symbol, determining whether the ratio is greater than a first threshold, and recognizing that the first symbol suffers from impulsive interference when the first ratio is greater than the first threshold.
Pilot pattern for observation-scalar MIMO-OFDM
In an embodiment, a transmitter includes a transmission path configurable to generate first pilot clusters in response to a matrix, each first pilot cluster including a respective first pilot subsymbol in a first cluster position and a respective second pilot subsymbol in a second cluster position such that a vector formed by the first pilot subsymbols is orthogonal to a vector formed by the second pilot subsymbols, the matrix having a dimension related to a number of cluster positions in each of the first pilot clusters. For example, where such a transmitter transmits simultaneous orthogonal-frequency-division-multiplexed (OFDM) signals (e.g., MIMO-OFDM signals) over respective channels that may impart inter-carrier interference (ICI) to the signals due to Doppler spread, the pattern of the pilot symbols that compose the pilot clusters may allow a receiver of these signals to estimate the responses of these channels more accurately than conventional receivers.
Signal receiving method and electronic device
An electronic device including a first transceiver configured to process a first carrier, a second transceiver configured to process a second carrier, a switch, a baseband processor configured to process a first baseband signal and a second baseband signal, which are processed respectively by the first transceiver and the second transceiver, an antenna connected through the switch in association with some of a plurality of reception paths with respect to the first carrier, and a reception path configured to provide the second transceiver with the first carrier received via the antenna connected through the switch to the second transceiver.
Method and system for mitigating interference by rotating antenna structures
Aspects of the subject disclosure may include, for example, obtaining data regarding interference detected in a received communication signal, and performing polarization adjusting by rotating one or more radiating elements of an antenna system such that an impact of the interference on the antenna system is minimized. Other embodiments are disclosed.
Minimizing the impact of in-band interference in transmissions to a customer premises equipment (CPE) device
A plurality of signal quality values that characterize signal qualities of the corresponding OFDM channel's subcarriers of a channel used by a first cable modem to communicate with an aggregation device are received. Due to in-band interference it is determined that a first subcarrier has a first signal quality value outside of a desirable signal quality threshold range for a pre-determined period of time. The aggregation device that provides data to the first cable modem is identified. To mitigate the interference impact, a signal analyzer sends an instruction to the aggregation device that identifies the first subcarrier and the first cable modem and that instructs the aggregation device to reduce a first transmission data rate used to transmit data on the first subcarrier.
Method and system for polarization adjusting of orthogonally-polarized element pairs
Aspects of the subject disclosure may include, for example, obtaining data regarding interference detected in a received communication signal, and performing polarization adjusting for one or more orthogonally-polarized element pairs of an antenna system such that an impact of the interference on the antenna system is minimized. Other embodiments are disclosed.