207 results about "Single input multiple output" patented technology

A radar system has different modes of operation. In one mode the radar operates as a single-input, multiple-output (SIMO) radar system utilizing one transmitted signal from one antenna at a time. Codes with known excellent autocorrelation properties are utilized in this mode. At each receiver the response after correlating with various possible transmitted signals is measured in order to estimate the interference that each transmitter will represent at each receiver. The estimated effect of the interference from one transmitter on a receiver that correlates with a different code is used to mitigate the interference. In another mode, the radar operates as a MIMO radar system utilizing all the antennas at a time. Interference cancellation of the non-ideal cross correlation sidelobes when transmitting in the MIMO mode are employed to remove ghost targets due to unwanted sidelobes.

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.

A method and communication system for selecting a mode for encoding data for transmission in a wireless communication channel between a transmit unit and a receive unit. The data is initially transmitted in an initial mode and the selection of the subsequent mode is based on a selection of first-order and second-order statistical parameters of short-term and long-term quality parameters. Suitable short-term quality parameters include signal-to-interference and noise ratio (SINR), signal-to-noise ratio (SNR), power level and suitable long-term quality parameters include error rates such as bit error rate (BER) and packet error rate (PER). The method of the invention can be employed in Multiple Input Multiple Output (MIMO), Multiple Input Single Output (MISO), Single Input Single Output (SISO) and Single Input Multiple Output (SIMO) communication systems to make subsequent mode selection faster and more efficient. Furthermore the method can be used in communication systems employing various transmission protocols including OFDMA, FDMA, CDMA, TDMA.

A method and an apparatus reduce power used when a traffic load is low in a base station of a wireless communication system. The base station monitors a traffic load. When the traffic load is lower than a predetermined threshold and a Multiple Input Multiple Output (MIMO) mode is used to communicate with a mobile station, the MIMO mode is converted to a Single Input Multiple Output (SIMO) mode. The base station performs communication with the mobiles stations by using the SIMO mode. According to another embodiment, when the traffic load is lower than a predetermined threshold, the base station limits the number of Resource Blocks (RBs) that may be allocated to a coverage area of the base station. A Power Amplifier (PA) bias related to a transmission output of the base station is reduced based on the limited number of RBs, thereby saving power consumption of the base station.

A method of indicating destination stations, performed by an access point (AP), in a wireless local area network (WLAN) system supporting multi-user multiple input multiple output (MU-MIMO) is provided. The method includes transmitting a sounding request frame to the plurality of destination stations to transmit a sounding frame used for channel estimation between the AP and each destination station, receiving the sounding frame in response to the sounding frame request from each station, and transmitting a first data frame spatially multiplexed with respect to the plurality of destination stations by performing channel estimation on the basis of the sounding frame, wherein the sounding request frame comprises a group identifier (ID) indicating the plurality of destination stations.

A Multiple Input Multiple Output (MIMO) radar system and method of using it for target recovery are disclosed. The MIMO radar system comprises an array of distributed radiating elements configured to transmit signals towards a target scene, an array of distributed receiving elements configured to receive signals backscattered from the target scene, a sampling module configured to sample the signals received, and a hardware processor configured to recover from the samples position parameters of one or more targets. Range, direction and optionally velocity, are estimated via simultaneous 2D or 3D sparse matrix recovery, wherein all channels defined by transmitter-receiver pairs are processed together. The digital processing may be applied either in Nyquist or sub-Nyquist scheme, reducing the number of samples, transmit and / or receive antennas. The radar system is optionally further enhanced by cognitive transmission scheme where transmitted signals are distributed over a wide frequency range with vacancy bands left therein.

A power transmission for mixed power vehicles located between an engine and an automatic speed variator consists of a generator, a clutch, a one-way clutch and a planetary gear mechanism consisting of a solar wheel, a planet wheel, a planetary frame and a gear ring. The planet wheel is externally engaged with the solar wheel and internally engaged with the gear ring separately. The output shaft of the engine is connected with the gear ring through a flange, the rotor of the generator is connected with the central shaft of the solar wheel through a spline and the planetary frame is connected with the input shaft of the automatic speed variator through a flange. On the output shafts of the engine and the planetary frame is disposed the one-way clutch separately and between the gear ring and the planetary frame is disposed the clutch.

When performing communication with a mobile station using MIMO-OFDM communication, a base station uses multiple input multiple output (MIMO) communication, which is multiple data stream transmission, to transmit data and pilot signals in a case where the communication environment of the mobile station is good, or uses single input multiple output (SIMO) communication, which is single data stream transmission, in a case where the communication environment of the mobile station is poor. When performing that SIMO communication, the base station performs control so that pilot signals from a specified cell that are used in channel estimation in single data stream transmission and pilot signals from adjacent cells that are used in channel estimation in single data stream transmission do not overlap in the frequency direction and / or time axis direction.

Apparatus and method for providing for packet data communication between a single-input-single-output (SISO) transceiver and a single-input-multiple-output / multiple-input-single-output (SIMO / MISO) transceiver. Receive channel coefficients representing relative strengths of individual signals received via multiple spatially diverse antenna elements and corresponding to a wireless data signal originating from a particular SISO radio frequency (RF) transceiver are used to provide substantially complementary transmit channel coefficients for use in producing outgoing RF signals to be transmitted via the same antenna elements for reception by such particular SISO RF transceiver.

A filter device and method for suppressing effects of Adjacent-Channel Interference of a received signal in a Frequency-Division-Multiple-Access system by filtering a baseband signal of the received signal. The filter device comprises an interference filter, which is a complex digital Single-Input-Multiple-Output, SIMO, filter that is adapted to simultaneously generate a first signal filtered at an upper-frequency-band and a second signal filtered at a lower-frequency-band, wherein the first signal is separate from the second signal. The filter device also comprises a selector adapted to select one of the signals as the output from the filter device.

A wireless network includes at least one Multiple Input Multiple Output (MIMO) wireless network station and two or more physical layer repeaters. Each of the physical layer repeaters is for receiving a wireless signal to or from the at least one MIMO wireless network station and re-transmitting the wireless signal while continuing to receive the wireless signal. The repeaters may be either frequency translating repeaters or non-frequency translating repeaters.

The invention is suitable for the technical field of communication and provides a pre-code achieving method, a pre-code achieving device and a multiple input multiple output (MIMO) system. The pre-code achieving method comprises the steps of receiving channel state information sent by multiple user devices; selecting a preset number of user devices from users for being paired to perform user pairing of multiple-user MIMO; selecting actual pre-code type according to a preset strategy, performing pre-code treatment to data of the selected multiple user devices according to the pre-code type to produce pre-code words of the multiple-user MIMO; broadcasting the preset number of pre-code words of the multiple-user MIMO and demodulation reference signals corresponding to the pre-code words of the multiple-user MIMO to the multiple user devices. On the one hand, the performance of the multiple-user MIMO or cooperative multiple-point transmission COMP is improved; on the other hand, a pre-code achieving system easily achieves user MIMO or the cooperative multiple-point transmission COMP.

Certain aspects of the present disclosure provide techniques and apparatus for using a Media Access Control (MAC) address of a station (STA) sending a direct link multi-user multiple-input multiple-output (MU-MIMO) transmission such that one or more STAs receiving the transmission may interpret a group identifier (ID) indicating a group to which the STAs belong. Using the group ID and the MAC address allows a STA to independently manage its group IDs, independent of an access point (AP) or other STAs in a Basic Service Set (BSS).

The present invention discloses a multiple human-targets location and tracking method based on multichannel phase comparison location. The method comprises: based on a linear frequency modulation continuous wave radar system of single input multiple output, employing the moving target indication and de-mean method to perform preprocessing of experiment data and perform diploid interpolation refinement distance dimension windowing Fourier transform of each period of the echo data so as to obtain object distance information according to the distance spectrum of an object; obtaining the object distance information according to the object distance; extracting the phase information corresponding to the target from the peak value where a frequency spectrum object is located; fusing the phase information of different receiving channels, calculating the phase differences among different receiving channels, calculating the azimuth or the pitch angle of the object, and combining the object distance information to calculate the location result of the object at a two-dimensional plane or a three-dimensional plane; and finally, employing the Kalman filtering method to realize the tracking of the target. The multiple human-targets location and tracking method based on the multichannel phase comparison location can perform detection, location and tracking of a plurality of human body objects indoors and outdoors so as to effectively reject multiple paths while keeping the target and perform accurate location of the object.

Angle estimation for modulated signal. A novel compensation technique is presented by which angle estimation may be performed for a modulated signal. More specifically, the angle between a constellation corresponding to a received signal and a constellation corresponding to a received signal may be very efficiently estimated using any one of the possible embodiments corresponding to various aspects of the invention. After this angle has been estimated, the received signal or the expected constellation may be rotated (or de-rotated) to compensate for this angular difference. In doing so, better estimates of the information bits that are demodulated and decoded from the received signal may be made. This approach may be implemented and adapted to any of a wide variety of communication systems including, but not limited to, single-input-multiple-output (SISO), single-input-multiple-output (SIMO), multiple-input-single-output (MISO), multiple-input-multiple-output (MIMO), and even space-time block code (STBC) communication systems or other communication systems.

The invention provides a large-scale MIMO (Multiple Input Multiple Output) self-adaptive multi-beam forming method in a high speed scene. Specifically, the method is that the large-scale MIMO wave forming design in the high speed scene is carried out based on a direction of arrival DoA specific to the strong correlation of MIMO channels resulting from clear sparse scatterers and LOS (Line of Sight) paths in a high-speed rail environment. Beam forming is carried out on each vehicular mobile carriage terminal MCT. The number of transmitting antennas required by each sub-beam is self-adaptively adjusted through calculation of signal to interference plus noise ratios SINRs of different sub-beams. When a trail is far away from a base station, the interferences among the sub-beams are serious. According to the method provided by the invention, the number of the sub-beams can be self-adaptively adjusted according to the total capacity of a system, and the performance of the system is improved.

The invention discloses an uplink secure transmission method based on downlink auxiliary feedback in a 5G communication system. In the first stage, a multi-antenna base station end sends both artificial interference and artificial noise signals on a downlink by means of a wave beam formation technology; and a single-antenna user end receives an emission signal from the base station end, and scrambles the received signal to a to-be-sent secret signal so that a mixed emission signal is formed. In the second stage, the user terminal broadcasts the mixed emission signal; and the base station end receives the mixed emission signal. Since the base station end already knows an artificial interference signal emitted by the base station itself, an expected secret signal can be separated from the received signal. A single-antenna passive eavesdropping end receives mixed signals during both transmission stages, and cannot know any prior information about the artificial interference and artificial noise signals, so the possibility of stealing secret information is low. Therefore, the transmission security of a 5G uplink single-input and multi-output system is effectively guaranteed.

The invention provides a data reading and writing method, a data reading and writing device and a circle queue. The method comprises the steps of acquiring a deviation position of a writing pointer from a queue head of the circle queue; determining a deviation position of a reading pointer according to the deviation position of the writing pointer; and reading data from the circle queue accordingto the deviation position of the reading pointer. According to the data reading and writing method, the data reading and writing device and the circle queue, single-input multi-output of a shared memory is implemented so that multiple reading threads can read data from the circle queue in parallel, thus the data reading and writing efficiency is effectively improved and the memory consumption is reduced.

The invention relates to a space division mode switching method of a single-user MIMO (Multiple Input Multiple Output) system based on SWIPT, belonging to the field of space division mode switching of MIMO systems. The problem that the existing space division mode switching method of the MIMO system is incapable of randomly switching between an energy mobile phone mode and an information decoding mode can be solved. The space division mode switching method of the single-user MIMO system based on SWIPT comprises the following steps that: information transmission is carried out by selecting a user having best conditions at first; power is distributed according to a power allocation algorithm; the sum-rate of the system is calculated according to a formula as shown in the specification; the sum-rate of the system is compared with the lowest transmission rate requirement Rmin of the system; if requirements of the system are not satisfied, the number of antennas is increased, so that the sum-rate of the system is calculated again till the requirements of the system are satisfied; all other antennas are used for energy harvesting; energy distribution and transmission can be carried out according to an energy beam forming algorithm; and the sum of energy harvested by a receiving end is finally calculated according to a formula as shown in the specification. The space division mode switching method of the single-user MIMO system based on SWIPT disclosed by the invention is applied to switching working modes of the single-user MIMO system based on the SWIPT technology.

The invention provides a multi-parameter estimation method for a micro-motion target under a non-Gaussian background. The method comprises the steps of: based on a single input multiple output (SIMO) radar system, calculating an autocorrelation entropy matrix of each receiving channel for each distance unit by using a Gaussian kernel function; then, performing mutual correlation processing on the autocorrelation entropy matrixes of every two channels to obtain multiple groups of mutual correlation entropy matrixes; fusing the obtained mutual correlation entropy matrixes in an arithmetic fusion mode; and finally, performing phase comparison monopulse positioning on multi-channel echo signals, thus positioning the micro-motion target. The method can realize multi-micro-parameter estimation and target positioning for the micro-motion target under the non-Gaussian background, and can obtain better estimation performance while estimating target parameters.

A rake receiver having a plurality of rake fingers is adapted based on a plurality of received signals. The plurality of received signals correspond to a single signal transmitted by a single antenna transceiver and received by a multiple antenna transceiver that includes the rake receiver. Each of a plurality of groups of rake fingers corresponds to a single-input, multiple output (SIMO) channel estimate. One coefficient from each of the plurality of SIMO channel estimates is selected, and a transmit steering vector is calculated based on the selected coefficients. The transmit steering vector is applied to a signal to be transmitted by the multiple antenna transceiver to the single antenna transceiver.

The invention discloses a visible light communication MIMO (Multiple Input Multiple Output) system giving consideration to positioning. The visible light communication MIMO system comprises a transmitting terminal and a receiver, wherein the transmitting terminal comprises N LEDs (Light-Emitting Diodes); each LED is used for sending a plurality of independent data packets; a data frame at a first preset position of each data packet is a functional frame; each LED sends an optical signal with position information of the LED under equal power in a gap at a position corresponding to a number of the LED; at a position of a second data frame, N LEDs can simultaneously send a channel response training sequence according to a modulation mode and carry out combined channel response estimation; the receiver can obtain an MIMO channel matrix according to distribution of strength of the optical signals sent by the N LEDs and is used for demultiplexing N paths of signals; and meanwhile, the receiver can decode out the LED position information carried in the optical signals so as to implement visible light positioning. The visible light communication MIMO system has the following advantages that the data frames combine positioning of ID (Identity) information and acquisition of the channel matrix; and when visible light positioning is implemented, an effective load proportion in the data frames is improved.

The disclosure provides a downlink transmission method for a Multiple Input Multiple Output (MIMO) system, and a base station, wherein the method comprises: a base station selecting a downlink MIMO mode in a downlink transmission mode in which a UE currently is by using a Channel Quality Indicator (CQI), a Rank Indicator (RI) and a Preceding Matrix Indicator (PMI) which are reported by the UE within a time window; and the base station transmitting data to the UE by using the selected downlink MIMO mode. The disclosure achieves the effect of increasing the coverage and capacity of the LTE system to the maximum.

The invention provides a modeling method of the transient process of an aero-engine, and belongs to the field of modeling and simulating of the transient state of the aero-engine. By distinguishing a dynamic model of the aero-engine in different steady states and combining the dynamic model with a corresponding steady-state model, the transient process of the aero-engine is presented as a dynamic variable parameter model through methods of polynomial fitting and a least squares support vector machine. The approximate transient process of multiple discrete steady state points is improved, the dynamic characteristics are better, and the situation that by means of an existing method, error accumulation exists when modeling of the transient state is conducted through output accumulation is improved; meanwhile, single input multiple output is modeling through the method, universality is wider, modeling can be promoted to modeling of the transient process of multiple input multiple output aero-engine through proper adjustment.

The invention discloses an MIMO transmission system based on optical frequency combing sources and wavelength division multiplexing. The MIMO transmission system based on optical frequency combing sources and wavelength division multiplexing comprises a central station, a transmission module and a base station, wherein the central station comprises a laser source for generating laser signals, a optical frequency combing module for generating multiple optical frequency combing sources according to the laser signals, a first wavelength division multiplexing module for separating the multiple optical frequency combing sources into a plurality of single optical frequency combing sources one by one, a space-time coding module for generating multiple space-time coding signals according to multiple high-speed MIMO baseband signals, and a plurality of electro-optical modulating modules; every electro-optical modulating module generates at least one MIMO signal according to at least one optical frequency combing source and at least one time-space coding signal; the transmission module transmits the multiple MIMO signals output by the plurality of electro-optical modulating modules; the base station comprises a plurality of opto-electrical detecting modules and a plurality of MIMO antennas, every opto-electrical detecting module detects at least one MIMO signals, and every MIMO antenna transmits a single MIMO signal. The MIMO transmission system based on the optical frequency combing sources and the wavelength division multiplexing can achieve transmission and frequency conversion of multiple MIMO signals through a single laser source.

The method and system for channel estimation in a single channel (SC) single-input multiple-output (SIMO) system described herein may provide a fast and cost effective approach to concurrently determine propagation channel estimates in a single-transmit (1-Tx) and multiple-receive (M-Rx) antennas wireless communication system. A single weight baseband generator may comprise a set generator, a channel estimator, and an algorithm generator. The set generator may generate orthogonal function sequences that may be applied to the M receive antennas and may be utilized by the channel estimator to generate channels estimates. The orthogonal function sequences may be transferred to the channel estimator after a delay. The algorithm generator may generate phase values based on the channels estimates that may be applied to the M receive antennas to improve the system's signal-to-noise performance.

The disclosure provides a downlink transmission method for a Multiple Input Multiple Output (MIMO) system, and a base station, wherein the method comprises: a base station selecting a downlink MIMO mode in a downlink transmission mode in which a UE currently is by using a Channel Quality Indicator (CQI), a Rank Indicator (RI) and a Preceding Matrix Indicator (PMI) which are reported by the UE within a time window; and the base station transmitting data to the UE by using the selected downlink MIMO mode. The disclosure achieves the effect of increasing the coverage and capacity of the LTE system to the maximum.