2723 results about "Multi output" patented technology

Provided is a method for managing resource in a high capacity wireless communication system capable of communicating with two or more users in a multi-input multi-output (MIMO) scheme when a base station transmits data. The includes: transmitting a MU-MIMO request-to-send (RTS) message to stations intending to transmit data in the MIMO scheme, and sequentially receiving a clear-to-send (CTS) message from stations intending to receive the data; transmitting a transmission ACK message to the stations, wherein the transmission ACK message includes information which prevents data collision during a time of data transmission to the stations and ACK signal; and configuring data to be transmitted to the stations into aggregated packets (A-MPDUs), transmitting the A-MPDUs to the stations in the MIMO scheme, and receiving a block ACK message from the stations.

The present invention relates to a multi-input multi-output (MIMO) antenna with a multi-band characteristic which includes a plurality of MIMO antenna, each having a pair of antenna elements, to support multiple bands, and is capable of guaranteeing high antenna efficiency for different bands by minimizing an interference between antenna elements of each MIMO antenna to improve an isolation characteristic. The MIMO antenna system having a multi-band characteristic, which includes two pairs of antenna patterns to support different band and coupling antenna parts separated from and coupled with the pairs of antenna patterns, can improve an isolation through the coupling antenna parts and guarantee an antenna gain. Moreover, since signal interference caused by the coupling effect can be cancelled to guarantee a band width with no change in antenna characteristics, it is possible to constructing two or more antennas to support a multi-band while guaranteeing stable operation of the antennas.

A rate-adaptive method of communicating over a multipath wireless communication system uses multiple links such that each end of a link uses multiple transmit and receive antennas. A number of independent streams that are to be transmitted for each link is determined based on an overall system performance measure. In addition, the system may also jointly determine the best modulation, coding, power control, and frequency assignment for each link, based on an overall system performance measure. In OFDM systems, the number of independent streams, as well as the modulation, coding, and power control, may be determined on a tone-by-tone basis based on an overall system performance measure.

Systems and methods are described that provide not only time but also phase synchronization, thus enabling distributed multiuser multiple-input multiple-output (MIMO) architectures and techniques, such as supported by the IEEE 802.11n standard, where several access points are connected to a central server and operate as a large distributed multi-antenna access point. The systems and methods can lock the phase of all access points using a common reference (e.g., a synchronization tone) broadcasted over the air in conjunction with a predictive filter (e.g., a Kalman filter) which closely tracks the phase drift for each subcarrier channel.

There is disclosed a method of a user equipment feeding back channel state information in a wireless communication system, comprising receiving a reference signal from a base station; generating first channel state information by measuring the reference signal; generating second channel state information based on the first channel state information; and transmitting the first channel state information and the second channel state information to the base station. The first channel state information is channel state information of a single user single cell Multi-input Multi-Output (MIMO) mode, and the second channel state information is channel state information of a multi-user MIMO (MU-MIMO) mode or a Cooperative Multiple Points Transmission and Reception (CoMP) mode.

The invention provides a method of operating a communication system. A channel matrix of a gain and phase between each transmit antenna and each receive antenna of the communication system is provided. At least one receive weight vector is computed as a function of the channel matrix and at least one of transmit weight vectors. An updated transmit weight vector is computed as a function of the transmit weight vector, the receive weight vector, the channel matrix.

A method transmits and receives signals in a cooperative, multi-user, multi-input, multi-output network. The network includes base stations (BSs) and mobile stations (MSs). Each BS has at least two antennas, and each MS has at least one antenna. At a first base station and a second base station using linear pre-coding matrices, a plurality of data streams are jointly pre-coded to produce first signals and second signals. The first signals are transmitted synchronously from the first BS and the second BS to a first MS, and the second signals are transmitted synchronously from the first BS and the second BS to a second MS, and in the first signal and the second signal are asynchronous with respect each other.

A Multi Input Multi Output (MIMO) Wireless Communication System method and apparatus are proposed whereby in a 2-way wireless communication system with scattering, random and imperfectly estimated propagation channels the ubiquitous and inherent MIMO cross-talk interference problem is solved so that robust and predictable Extended Communication Range and Extended Data Rate are achieved.

An approach is provided for supporting transmission in a multi-input-multi-output (MIMO) communication system including a plurality of terminals. A preamble portion of a frame is transmitted by a multiple transmit antennas of a hub using Orthogonal Frequency Division Multiplexing (OFDM) to the terminals over a channel, wherein each of the terminals determines a characteristic of the channel with respect to the transmit antennas as feedback information. The hub receives the feedback information from the terminals. The hub selects, according to the feedback information, a subset of the antennas for transmission of a remaining portion of the frame to the terminal.

Using precoded space multiplexing of limited fed back, the method defines a group of set of precoded matrix (i.e. precoded codebook) known by transmitter and receiver. Using algorithm of channel estimation to obtain current state information of channel, the receiver selects an optimal precoded matrix from precoded codebooks according to minimized principles of trace of mean square error matrix as well as through a feedback channel, feeds index of the precoded matrix back to the transmitter within coherence time of channel. Based on the said index of the precoded matrix, the transmitter obtains the precoded matrix, and then carries out precoded operations on vectors of transmit signal based on the precoded matrix. Precoded codebook can be designed based on maximized principle of minimum distance between two norms of projections of subspaces. Using limited bit number fed back, the invention raises communication performance.

The invention discloses a power grid security situation predicting method based on an improved deep learning model and belongs to the technical field of power system safety. The power grid security situation predicting method includes: performing power grid security situation evaluation through power grid data collection and preprocessing; aiming at the characteristic that indicator data of power grid security situation evaluation are high in relevance and dimension, providing an improved self-coding network method to lower dimension of the indicator data, and utilizing a data sample after dimension reduction and a power grid security situation value corresponding to a next time monitoring point; adopting an improved deep belief network to build a deep learning situation predicting model with multi-input and multi-output for power grid security situation prediction. By the power grid security situation predicting method, speed and accuracy of power grid security situation prediction can be improved effectively.

Precoding methods and method for performing precoding and methods of transmitting feedback information for precoding or transmitting a signal using a multi-codebook and method of transceiving precoding information in a multi-antenna system, where a signal transmitting method in a multi-antenna system, and more particularly, a method of transceiving precoding matrix information for a multi-input multi-output (MIMO) system is disclosed. The present invention proposes a method of performing communications using an expanded unitary matrix generated from shifting a phase of a base unitary matrix. The present invention is applicable to single user MIMO, multi-user MIMO, beam forming, etc.

This invention is related to a deep multi-sensor fusion system for inter-radar interference-free environmental perception comprising of (1) polystatic Multi-Input Multi-Output (MIMO) radars such as radio frequency radar and laser radar; (2) vehicle self-localization and navigation; (3) the Internet of Vehicles (IoV) including Vehicle-to-Vehicle communication (V2V), Vehicle-to-Infrastructure communication (V2I), other communication systems, data center / cloud; (4) passive sensors such as EOIR, and (5) deep multi-sensor fusion algorithms. The self-localization sensors and V2X formulate cooperative sensors. The polystatic MIMO radar on each vehicle utilizes both its own transmitted radar signals and ones from other vehicles to detect obstacles. The transmitted radar signals from other vehicles are not considered as interference or uselessness as conventional radars, but considered as useful signals to formulate a polystatic MIMO radar which can overcome the interference problem and improve the radar performance. This invention can be applied to all kinds of vehicles and robotics.

A multi-output dual polarity inductive boost converter includes an inductor, a first output node, a second output node, and a switching network, the switching network configured to provide the following modes of circuit operation: a first mode where the positive electrode of the inductor is connected to an input voltage and the negative electrode of the inductor is connected to ground; 2) a second mode the negative electrode of the inductor is connected to ground and the positive electrode of the inductor is connected in sequence to one or more of the fourth and fifth output nodes; and 3) a third mode where the positive electrode of the inductor is connected to the input voltage and the negative electrode of the inductor is connected in sequence to one or more of the first, second and third output nodes.

A method of transmitting a precoding matrix in a multi-input, multi-output (MIMO) system is disclosed. In the system, a receiving end determines feedback information by calculating each diagonal sub-matrix of the precoding matrix. Here, the precoding matrix includes a plurality of sub-matrices arranged in a block diagonal format. Thereafter, the receiving end transmits he feedback information of the each calculated sub-matrix.

Power control for devices having multiple transmit antennas are disclosed, including power control methods for Physical Uplink Control Channel (PUCCH) and Sounding Reference Signal (SRS) transmissions for a wireless transmit / receive unit (WTRU). The PUCCH and SRS power control methods include selecting a multiple input multiple output (MIMO) mode and changing the power of the PUCCH or SRS transmission based on the selected MIMO mode. Another power control method estimates an antenna gain imbalance (AGI) for a WTRU having at least two transmit antennas. The AGI is based on measuring a Reference Signal Received Power (RSRP) on each transmit antenna. Each transmit antenna is then scaled by an AGI scaling factor based on the estimated AGI.

A current resonant DC-DC converter of multi-output type is provided which comprises an output-regulatory MOS-FET 40 connected between a secondary winding 5c of a transformer 5 and a smoothing capacitor 16 in a second rectifying smoother 17, and an output control circuit 41 for controlling the on-off operation of output-regulatory MOS-FET 40 based on voltage VO2 from smoothing capacitor 16 in second rectifying smoother 17. By turning the on-off operation of output-regulatory MOS-FET 40 in synchronization with switching frequency of first or second MOS-FETs 1, 2, an ideal cross regulation among respective DC outputs can be obtained, providing the inexpensive converter with simple circuit alteration capable of producing highly stable DC outputs with high power conversion efficiency, high accuracy and less power conversion loss.

The per antenna capacity of each of the transmitter antennas in a MIMO system are individually determined from measurable information at the receiver end. Specifically, the channel capacity for each individual transmitter antenna is calculated at the receiver end as a function of measurable channel coefficients (also known as channel state information), the measurable average signal-to-noise ratio, and the number of transmitter antennas. Once the per antenna capacity of each transmitter antenna is individually determined at the receiver end, the maximum transmission rate for each data stream transmitted by each transmitter antenna is determined from that individual capacity either at the receiver end and fed back to the transmitter end, or is determined at the transmitter end from the individual transmitter antenna capacities that are fed back by the receiver end to the transmitter end. A modulation scheme that supports each maximum transmission rate is then determined based on some defined criteria.

Methods and systems for encoding and decoding signals using a Multi-input Multi-output Time Encoding Machine (TEM) and Time Decoding Machine are disclosed herein.

A signal processing apparatus in a multi-input / multi-output (MIMO) communication system includes a transmitting end in which a code rate is differently set and a respectively different modulation method is performed at each antenna in consideration of a channel situation of each transmission antenna, coded bits are separately interleaved, and then collectively interleaved to transmit data, and a receiving end in which received data is collectively deinterleaved and then decoded and deinterleaved separately according to each reception antenna, and a channel situation of each signal received from multiple transmission antennas is estimated and fed back to the transmitting end. A different coding rates and modulation method are used at each transmission antenna and the spatial interleaving is performed to obtain a diversity gain in a space domain, and thus, the communication quality can be enhanced.

A shift register is disclosed, which can prevent a multi-output caused by a coupling phenomenon, the shift register comprising at least two clock transmission lines which transmit at least two clock pulses provided with the phase difference; and a plurality of stages which are supplied with the clock pulses from the clock transmission lines, and output output-signals in sequence, wherein each of the stages comprises a pull-up switching unit which is supplied with the first clock pulse, and outputs the first clock pulse as the output-signal according to a signal state of an enable node; and a noise eliminating unit which responds to the second clock pulse of which phase is prior to that of the first clock pulse supplied to the pull-up switching unit, and supplies a start pulse externally provided or the output-signal provided from the preceding stage to the enable node.

Systems and methods are provided for determining a channel quality indicator (CQI) in a transmission system associated with a diversity transmission scheme. A plurality of independent diversity branches are identified in the diversity transmission scheme. Each one of the independent diversity branches may correspond to a different portion of the effective channel and may include any suitable combination of frequency, time, and / or spatial components of the effective channel or of any wired or wireless paths or combinations of the same. An effective Signal-to-Noise Ratio (SNR) value is computed for each one of the identified independent diversity branches. The computed effective SNR values are combined for the identified independent diversity branches to generate a CQI value.

Techniques are described that provide uplink power control techniques that can support different uplink multi-input multi-output (MIMO) transmission schemes. Open and closed loop power control schemes can be used to prescribe the power level of the mobile station.

In a communication system, and in particular a wireless Orthogonal Frequency Division Multiplexing (OFDM) communication system, the present invention provides systems for estimating parameters of a channel across which a signal is transmitted. The present invention may be used in a Multi-Input, Multi-Output (MIMO) system in which the data is transmitted from any number of transmitting antennas and received by any number of receiving antennas. The number of transmitting and receiving antennas does not necessarily have to be the same. Circuitry is provided for calculating parameters indicative of the characteristics of the communication channel. Estimates of channel parameters may include channel estimates and noise variance estimates.

The invention provides a pre-coding method for an MIMO (multi-input multi-output) system of 8 transmitting antennas. A dual code text is adopted in the method, and the dual code text is determined by selectively succeeding partial code words of LTE (long term evolution) and then performing certain extension. The method for pre-coding by using the dual code text reduces the feedback overhead of the system, acquires good performance gain, and is suitable for a multi-user multi-input multi-output (MU-MIMO) system.

A multi-output dual polarity inductive boost converter includes an inductor, a first output node, a second output node, and a switching network, the switching network configured to provide the following modes of circuit operation: a first mode where the positive electrode of the inductor is connected to an input voltage and the negative electrode of the inductor is connected to ground; 2) a second mode the negative electrode of the inductor is connected to ground and the positive electrode of the inductor is connected in sequence to one or more of the fourth and fifth output nodes; and 3) a third mode where the positive electrode of the inductor is connected to the input voltage and the negative electrode of the inductor is connected in sequence to one or more of the first, second and third output nodes.

The invention provides a calibration device and a calibration method of a multi-input multi-output (MIMO) terminal. The calibration device comprises a second antenna port, a feedback module, a radio frequency receiving module, a comparison module, a distortion degree determination module and a predistortion treatment module, wherein the feedback module is used for feeding back an output signal of a radio frequency emission module to the second antenna port; the radio frequency receiving module is used for obtaining a digitized feedback signal; the comparison module is used for comparing the feedback signal with an input signal and determining whether a power amplifier works in a nonlinear area or not according to a comparison result; the distortion degree determination module is used for determining the distortion degree of the feedback signal when the power amplifier works in the nonlinear area; and the predistortion treatment module is used for adjusting a predistortion coefficient according to the distortion degree when the power amplifier works in the nonlinear area so as to obtain a calibrated predistortion coefficient. The calibration device can be utilized to calibrate a predistortion coefficient lookup table so as to ensure that the MIMO terminal can carry out predistortion treatment by utilizing the calibrated predistortion coefficient lookup table in a working process so as to improve the linear performance of the power amplifier.

A system and methodology for channel equalization are provided. According to one aspect, a receiver structure for a MIMO system is provided that employs frequency domain equalization (FDE) with noise prediction (FDE-NP). The FDE-NP structure may include a feedforward linear frequency domain equalizer and a group of time domain noise predictors (NPs), which may operate by predicting a distortion corresponding to a given linearly equalized data stream based on previous distortions of all linearly equalized data streams. According to another aspect, a receiver structure for a MIMO system is provided that employs FDE-NP with successive interference cancellation (FDE-NP-SIC), which can extend the functionality of FDE-NP by ordering all linearly equalized data streams according to their minimum mean square errors (MMSEs) and detecting those streams which have a low MMSE first, thereby allowing current decisions of lower-indexed streams to be considered along with previous decisions for all data streams for noise prediction. According to a third aspect, a method for analyzing the performance of a MIMO system with equalization is provided. Pursuant to the method, a general expression of MMSE may first be derived. The MMSE expression may then be related to an error bound by applying the modified Chernoff bounding methodology in a general MIMO system. The parameters in the result may then be varied for applicability to single-input single-output (SISO), multiple-input single-output (MISO), and single-input multiple-output (SIMO) systems with receiver equalization technology.

The invention discloses a method for multi-input multi-output transmission for precoding. The method comprises the following steps: a fundamental matrix is selected, a column vector is selected from the fundamental matrix according to the dimension of a precoding matrix under each rank, the precoding matrixes are combined into codebooks, and the codebooks are respectively stored into the transmitting end and the receiving end of a multi-input multi-output transmission system; the receiving end selects precoding matrixes from the codebooks, and feeds back the indexes thereof to the transmitting end; the transmitting end uses the precoding matrixes corresponding to the indexes when the next transmission is performed, performs linear transformation in spatial domain to signals to be transmitted and then transmits the signals. The invention also discloses a method for multi-input multi-output codebook coding for precoding. The method enables the system to meet the feedback expenses and obtains good performance gain.