204 results about "Single input multiple output" patented technology

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 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.

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.

Aspects of a method and system for an optional closed loop mechanism with adaptive modulations for a multiple input multiple output (MIMO) WLAN system are provided. One aspect of the system may comprise a receiver that may select, for a plurality of spatial streams, a modulation type and / or coding rate. The receiver may communicate a message, via an RF channel, that comprises a plurality of modulation types and / or coding rates. The receiver may configure for receiving subsequent data based on at least one selected modulation type and / or coding rate. Another aspect of the system may comprise a transmitter that may receive a message, via an RF channel, that comprises a specification of, for a plurality of spatial streams, a plurality of modulation types and / or coding rates. The system may configure for transmitting subsequent data based on at least one of the received modulation types and / or coding rates.

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.

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.

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 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.

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.