Abstract: Disclosed are a spatial multiplexing method and apparatus using polarization in a multi-beam system. As the spatial multiplexing method using polarization in a multi-beam system, an embodiment of the present invention provides a spatial multiplexing method including determining different phases and different polarizations to be applied to a first beam and a second beam, precoding a signal so that the first beam and the second beam have the determined different phases, and converting polarization of the precoded signal so that the first beam and the second beam have the determined different polarizations.

Abstract: Novel channel estimation techniques that can be performed solely in the analog domain are provided. The techniques use continuous analog channel estimation (CACE), periodic analog channel estimation (PACE), and multiantenna frequency shift reference (MAFSR). These techniques provide sufficient channel knowledge to enable analog beamforming at the receiver while significantly reducing the estimation overhead. These schemes involve transmission of a reference tone of a known frequency, either continuously along with the data (CACE, MAFSR) or in a separate phase from data (PACE). Analysis of the methods show that sufficient receiver beamforming gain can be achieved in sparse channels by building the beamformer using just the amplitude and phase estimates of the reference tone from each receiver antenna.

Abstract: Disclosed herein is an analog-to-digital converter circuit configured for digitizing an analog input signal. The analog-to-digital converter comprises an analog input configured for receiving the analog input signal. The analog-to-digital converter circuit further comprises at least one sub-ADC connected to the analog input signal, wherein the at least one sub-ADC is configured to output at least one encoded output vector in response to receiving the analog input signal. The analog-to-digital converter circuit further comprises a lookup circuit comprising a nested lookup table. The lookup circuit is configured to select an output value from the nested lookup table using the at least one encoded output vector, wherein the lookup circuit is configured to provide the output value as the digitization of the analog input signal.

Abstract: A method, in a radio network node, comprises identifying, among a predetermined codebook of precoding matrix codewords, a subset of precoding matrix codewords that are not to be reported by the wireless device in channel-state-information, CSI, feedback, and transmitting, to the wireless device, a bitmap identifying the subset of precoding matrix codewords that are not to be reported by the wireless device; where each bit in the bitmap corresponds to only one combination of a first dimension index l?1 and a second dimension index l?2 out of the possible combinations of the first dimension index l?1 and the second dimension index l?2, and where the first dimension index l?1 and the second dimension index l?2 identify a two-dimensional beam, the two-dimensional beam being defined by a vector of complex numbers comprised within at least one column of a precoding matrix codeword in the codebook.

Abstract: A signal detection method for a MIMO-OFDM wireless communication system includes obtaining a channel matrix of each subcarrier through channel estimation for each MIMO-OFDM data packet in a plurality of MIMO-OFDM data packets; receiving a reception vector of each subcarrier; performing channel matrix preprocessing for the channel matrix of each subcarrier to generate a global dynamic K-value table, in which the global dynamic K-value table includes a global dynamic K-value corresponding to each search layer of each subcarrier; performing MIMO detection for each OFDM symbol in the MIMO-OFDM data packet, in which the MIMO detection includes performing the following steps for each subcarrier of a current OFDM symbol: reading channel matrix preprocessing results and reception vector of the current subcarrier; transforming the reception vector of the current subcarrier into an LR search domain; and performing K-best search for the current subcarrier to obtain an LR domain candidate transmission vector of the curre

Abstract: A system includes remote unit(s) (RU(s)). The RU(s) is/are configured to transmit at least one signal on a plurality of different beam patterns, each beam pattern comprising an active subset an inactive subset of a plurality of fine beams covering an area of a cell. The RU(s) is/are also configured to receive, from each of a plurality of user equipment (UEs) in the area, a respective signal strength measurement for each of the plurality of different beam patterns. The system also includes a centralized unit communicatively coupled to the plurality of RUs via a fronthaul interface. The centralized unit is configured to determine a bit vector for each UE based on a combination of the signal strength measurements from the respective UE. The centralized unit is configured also to select a respective fine beam for each UE based on the respective bit vector for the UE.

Abstract: Disclosed herein are a signal receiving apparatus capable of improving signal compensation performance and a signal processing method thereof. The signal receiving apparatus includes a terminal configured to receive a signal from an external device; and an equalizer configured to reduce inter-symbol interference of the signal received through the terminal. A swing level of an output signal output from the equalizer is maintained in a preset range.

Abstract: A radar system includes: a plurality of first receiving devices for generating a plurality of first digital signals according to a plurality of first incoming signals, respectively; and a plurality of second receiving devices for generating a plurality of second digital signals according to a plurality of second incoming signals, respectively. A processing device is arranged to perform a first beamforming operation to generate a plurality of first beamforming signals according to the plurality of first digital signals and a first gain matrix, and to perform a second beamforming operation to generate a plurality of second beamforming signals according to the plurality of second digital signals and a second gain matrix; and to determine an altitude angle of a first object and a second object, and to determine a first azimuth angle of the first object and a second azimuth angle of the second object.

Abstract: The present disclosure provides a pre-equalization compensation method and device for a link, a storage medium and an electronic device. The method includes: in response to that an Active Antenna Unit (AAU) is powered on, parsing a prestored off-line compensation table to obtain first non-flatness equalization coefficients of an RF link with a plurality of sub-carriers and second non-flatness equalization coefficients of a wave control link with the plurality of sub-carriers, with each one of the plurality of sub-carriers corresponding to one of the first non-flatness equalization coefficients and one of the second non-flatness equalization coefficients; combining the first non-flatness equalization coefficients of the plurality of sub-carriers and the second non-flatness equalization coefficients of the plurality of sub-carriers to obtain a combined carrier non-flatness coefficient; and performing equalization compensation on the link according to the combined carrier non-flatness coefficient.

Abstract: A transmission device of the disclosure includes: a generator unit that generates, on the basis of a control signal, a transmission symbol signal that indicates a sequence of transmission symbols; an output control unit that generates an output control signal on the basis of the transmission symbol signal; and a driver unit that generates, on the basis of the output control signal, a first output signal, a second output signal, and a third output signal. The generator unit generates the transmission symbol signal on the basis of the control signal, to allow the first output signal, the second output signal, and the third output signal to exchange signal patterns with one another.

Abstract: Technologies directed to co-channel interference detection using a signal correlation test are described. One method includes receiving a radio frequency (RF) signal and generating digital sample corresponding to the RF signal. The method further includes determining a first correlation coefficient using the digital samples, a first value, and a second value. The first value corresponds to a signal lag parameter and the second value corresponds to a cyclic frequency parameter. The method further includes determining a second correlation coefficient using the digital samples, the first value, and a third value corresponding to the cyclic frequency parameter. The second value and the third value are multiples of a fourth value. The method further includes determining, using the first correlation coefficient and the second correlation coefficient, that first RF signal comprises a first portion from a second communication device and a second portion from a third communication device.

Abstract: Embodiments of this application disclose a channel estimation method and apparatus, and relate to the field of communications technologies. One example method include: generating and sending indication information, where the indication information is used to indicate L space-frequency basis vectors for constructing an M×N-dimensional space-frequency vector; the space-frequency vector includes M N-dimensional precoding vectors, each precoding vector is used in one of M frequency bands, and the space-frequency vector is generated by performing a weighted combination on L space-frequency component vectors; each of the L space-frequency component vectors is a vector including M×N elements that are in one of the L space-frequency basis vectors, and each of the L space-frequency basis vectors is an Nf×N-dimensional vector; the space-frequency basis vector is a three-dimensional oversampled (DFT) vector; and L?2, Nf?M?1, N?2, and L, M, N, and Nf are all integers.

Abstract: A wireless communication device that implements beamforming includes: a storage, a processor, and a radio circuit. The storage stores directivity information that indicates a directivity of a radio intensity obtained when beams are formed in a plurality of main lobe directions designated in advance. The processor calculates, based on the directivity information, an interference to a first beam from a second beam when an instruction to form the first beam and the second beam is given. The first beam is configured to transmit a first signal in a first main lobe direction. The second beam is configured to transmit a second signal in a second main lobe direction. The processor generates, based on the calculated interference, a cancellation signal for canceling the second signal in the first main lobe direction. The radio circuit transmits the first signal and the cancellation signal.

Abstract: A wireless communication device includes first and second links. The first and second links respectively include first and second sets of antennae having an arrangement that renders a null space of a channel matrix between the first and second links non-zero. When the first and second links operate on a first frequency band, the first link obtains first channel state information that indicates a first channel measurement of a first set of channels observed from the second link to the first link. Based on the first channel state information, the first link determines a spatial mapping matrix that facilitates null steering of a signal transmission from the first link in a direction of the second link. The first link transmits to a remote device, a wireless signal on the first frequency band based on the spatial mapping matrix.

Abstract: Aspects described herein relate to communicating a beam report that includes beam measurements performed by one or more antenna panels and an identifier of the one or more antenna panels. The beam report may be used to determine a number of antenna panels supported by a user equipment (UE) transmitting the beam report, which may be used in configuring the UE for communicating with one or more other devices.

Abstract: An apparatus and method provide for receiving, from a network node, a set of reference signals. A set of beams are identified based on the set of reference signals. A subset of coefficients with non-zero values are determined from a set of coefficients, each coefficient of the subset of coefficients being associated with a pair of values comprising an amplitude value and a phase value, each coefficient of the set of coefficients corresponding to a respective beam of the set of beams for each respective layer of the set of layers and a respective frequency-domain index of a set of frequency domain indices for each layer of the set of layers. The set of layers are partitioned into a plurality of groups of layers. A beam bitmap vector is generated for each group of the plurality of groups of layers, the beam bitmap vector indicating a subset of beams of the set of beams within the layer-group, the subset of beams being associated with the subset of coefficients.

Abstract: Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may transmit capability information including information regarding a beamforming capability of the UE; receive configuration information indicating a beamforming configuration, wherein the beamforming configuration is based at least in part on digital beamforming, analog beamforming, or a combination thereof; and communicate in accordance with the beamforming configuration. Numerous other aspects are provided.

Abstract: A method of a user equipment (UE) for a channel state information (CSI) feedback in a wireless communication system is provided. The method comprises receiving, from a base station (BS), CSI feedback configuration information including a number (K0) of coefficients for the CSI feedback, deriving, based on the CSI feedback configuration information, the CSI feedback including K1 coefficients that are a subset of a total of Q coefficients, wherein K1?K0 and K0<Q, and transmitting, to the BS, the CSI feedback including the K1 coefficients over an uplink channel.

Abstract: A system includes a memory having instructions therein and at least one processor in communication with the memory. The at least one processor is configured to execute the instructions to determine a global-level importance magnitude value for a global-level importance of an explainable feature of a machine learning base model based on a first prediction of the machine learning base model. The at least one processor is also configured to execute the instructions to determine a global-level importance direction label for the global-level importance of the explainable feature based on the first prediction. The at least one processor is also configured to execute the instructions to generate a communication for presentation to a user based on a second prediction of the machine learning base model, based on the global-level importance magnitude value, and based on the global-level importance direction label.

Abstract: A time error vector is determined using pairs of two closest points of input-referred noise data that straddle respective crossing times indicating when a clock signal representation crosses a threshold value, a slew rate of the clock signal representation, and the crossing times. A system filter is applied to the time error vector in the frequency domain. A first RMS value is determined indicating a jitter value present in the filtered time error vector. A raw clock signal time error vector of the clock signal under test is generated, the system filter is applied to the raw clock signal time error vector in the frequency domain, and a second RMS value indicating a jitter content of the filtered raw clock signal time error vector is determined. The second RMS value is corrected using the first RMS value to thereby generate a jitter measurement compensated for input-referred noise.