526 results about "Mimo transmission" patented technology

A intelligent backhaul radio have an advanced antenna system for use in PTP or PMP topologies. The antenna system provides a significant diversity benefit. Antenna configurations are disclosed that provide for increased transmitter to receiver isolation, adaptive polarization and MIMO transmission equalization. Adaptive optimization of transmission parameters based upon side information provided in the form of metric feedback from a far end receiver utilizing the antenna system is also disclosed.

MIMO transmission methods are applied to communicaiton systems in which a transmitter has more than one transmit antenna and a receiver has more than one receive antenna. Information to be transmitted is divided into a plurality of subsignals according to the number of used transmit antennas and each subsignal is processed separately before it is emitted by the respective transmit antenna. In the receiver the different receive signals are processed thus that subsignals are detected and decoded and the contribution of each detected and decoded subsignal is subtracted from the receive signals and whereby a feedback channel from receiver to transmitter is used to send control information to the transmitter depending on the receive situation. In order to optimize the usage of the MIMO channel the invention proposes the in the receiver the link quality of each subsignal is determined and information of each subsignal is transmitted to the receiver via the feedback channel and that in the transmitter properties of the subsignals are controlled by the link quality information.

A method and system for cooperative multiple-input multiple output (MIMO) transmission operations in a multicell wireless network. Under the method, antenna elements from two or more base stations are used to from an augmented MIMO antenna array that is used to transmit and receive MIMO transmissions to and from one or more terminals. The cooperative MIMO transmission scheme supports higher dimension space-time-frequency processing for increased capacity and system performance.

A wireless communications system supporting multiple MIMO transmission modes supporting both diversity and directional transmissions under a plurality of different transmission modes comprises a plurality of transmit and receive antenna elements where the transmit antenna elements are arranged to provide polarization diversity. The transmitting station derives actual knowledge of the forward channel by feeding back certain information such as a preferred beam index and a channel quality indicator figure of merit for that beam from the receiving station to the transmitting station along a reverse channel. The receiving station knows the beam weights used by the transmitting station. The transmitting station applies the fed back information to transmit user data intended for the receiving station in the optimal fashion, such as along the preferred beam and at a time when forward channel conditions are satisfactory. The system provides robust single or multiple stream diversity transmission, together with the option of single user or multi-user beamforming to allow on-the-fly trade-offs between coverage gain and capacity in a wireless telecommunications system.

Single user and multiuser MIMO transmission in a cellular network may be performed by selecting by a base station (eNB) to transmit either one or two transmission layers. When one transmission layer is selected, a first transmission layer is precoded with a first precoder. A first demodulation reference signal (DMRS) sequence or a second DMRS sequence is selected by the eNB and precoded using the first precoder. The first transmission layer is transmitted with the selected precoded DMRS from the eNB to a user equipment (UE), and an indicator is transmitted to the UE to indicate which DMRS sequence is selected and transmitted.

Transmission with multiple antennas in a wireless network is performed by transmitting a plurality of reference sequences (RS) from a UE. A first RS s1[k] is produced using a first cyclic shift and a base sequence s0[k], wherein k={1, 2 . . . K} is an element index. A second RS s2[k] is produced using a second cyclic shift and s0[k]. A first symbol sequence x1[k] is produced using at least s1[k] and s2[k], for at least one k. A second symbol sequence x2[k] is produced using at least s1[k] and s2[k], for at least one k. x1[k] is transmitted using a first transmit antenna and x2[k] is transmitted using a second transmit antenna.

A method for communicating a plurality of data streams between a transmitting device with multiple transmit antennas and a receiving device, is disclosed. The method comprises determining a list consisting of a subset of the multiple transmit antennas on which the transmitting device will transmit data, determining a set of power weightings, providing the set of power weightings and the list of the subset of the multiple transmit antennas to the transmitting device, weighting a plurality of data streams by the power weightings, and transmitting the power weighted data streams on the subset of the multiple transmit antennas to the receiving device. Another aspect of the invention comprises maintaining a codebook consisting of a plurality of transmit weight vectors at both the transmitting device and the receiving device. The method also comprises determining a list consisting of a subset of the plurality of transmit weight vectors which to use for transmitting the multiple data streams, determining a set of power weightings to be use for each data stream, providing the set of power weightings and the list of the subset of the plurality of transmit weight vectors to the transmitting device, and weighting the data streams by the power weightings and beamforming the data streams with the subset of the plurality of transmit weight vectors.

A transmitter of a base station includes a data serial-to-parallel converter, M modulators, M beam formers, and transmission antennas. The data serial-to-parallel converter converts transmission data into M sequences. Each modulator modulates the transmission data. Each beam former weights the modulation signal to form directional beams. The transmission antennas narrow the beams and transmit the modulation signals in parallel (MIMO transmission). In a mobile station, a receiver has reception antennas for receiving data transmitted in parallel and an MIMO demodulator for demodulating the data.

A multiple-input multiple-output (MIMO) wireless communication system. A transmitter that includes a plurality of transmit antennas selects one of a spatial multiplexing scheme and a spatial diversity scheme, processes a signal in the selected transmission scheme, and transmits the signal through the plurality of transmit antennas. A receiver that includes a plurality of receive antennas processes a signal in a reception scheme mapped to a transmission scheme of the transmitter. The transmission schemes include a transmission scheme for maximizing diversity gain and a transmission scheme for maximizing spectral efficiency. The MIMO communication system using an adaptive transmission mode switching technique performs switching between MIMO transmission modes using spatial selectivity of a channel, thereby obtaining maximum gain in a signal to noise ratio (SNR) and spectral efficiency according to channel state.

A Channel Quality Indicator table for wireless multiple input multiple output (MIMO) networks is disclosed. In one embodiment, a method of generating a table for channel quality indicator (CQI) for an open loop MIMO transmission includes calculating performance of a link between a transmitter and a user end unit for each MIMO transmission mode over a range of average signal-to-noise ratio, and selecting the MIMO transmission mode that maximizes performance for each subset of the range of average signal-to-noise ratio. The method further includes storing the selected MIMO transmission mode and the corresponding subset of the range of average signal-to-noise ratio in a CQI table, the CQI table being stored in an user end unit and a base transceiver station of the open loop MIMO network.

The present invention provides an effective way to create a virtual MIMO transmission system using mobile terminals that have only one transmit path and antenna. This is accomplished by assigning mobile terminals to a group and assigning certain shared resources and user-specific resources to those mobile terminals in the group. In a synchronized fashion, the mobile terminals will provide uplink transmission in concert, as if they were a single entity having multiple transmission paths and antennas. Preferably, the shared resources bear on how the data is transmitted, and the user-specific resources relate to pilot signals. The data transmitted may be encoded in any number of ways, and in one embodiment, the mobile terminals may relay their information to each other, such that uplink transmissions can incorporate STTD decoding or other space-time codes. The invention is applicable to virtually any multiple access technology, including OFDM, TDMA, and CDMA, preferably synchronous CDMA.

A method and system for cooperative multiple-input multiple output (MIMO) transmission and reception operations in a multicell wireless network. Under the method, antenna elements from multiple base stations and/or multiple antennas are utilized to from an augmented MIMO antenna array that is used to transmit and receive MIMO transmissions at base stations and/or terminals. The cooperative MIMO transmission scheme supports higher dimension space-time-frequency processing for increased capacity and system performance.

The invention provides a reconfigurable intelligent surface assisted multi-user MIMO uplink transmission method. According to the transmission method, a signal sent by a user side is reflected to a base station through an RIS, and the RIS can change the phase of the signal incident on the RIS. Aiming at a bottleneck problem of channel information acquisition of an RIS-assisted multi-user MIMO transmission system, only partial channel state information is utilized, including instantaneous channel state information from the RIS to a base station channel and statistical channel state informationfrom a user to the RIS channel; through an alternate optimization method, a deterministic equivalence principle, a block coordinate descent method, an MM method and the like, a sending covariance matrix and an RIS phase shift matrix of a user are jointly designed to maximize the global energy efficiency of the system or traverse the spectral efficiency; when the channel state information is changed, the user side dynamically implements transmission power distribution with maximum energy or spectral efficiency, and the RIS dynamically adjusts the phase shift matrix. According to the invention,the implementation complexity is low, and the performance of multi-user MIMO uplink transmission can be effectively improved.

A method of link adaptation performed by an access point supporting multi user(MU) multiple input multiple output(MIMO) in wireless local area network system is provided. The method includes transmitting, to a first station, a physical layer convergence procedure (PLCP) protocol data unit (PPDU) containing a modulation and coding scheme(MCS) request(MRQ) and receiving, from the first station, a MCS feedback(MFB) in response to the MRQ, wherein the first station is one of destination stations of MU-MIMO transmission performed by the access point, and the MFB includes a recommended MCS value computed, by the first station, on the assumption that the first station, as a member of the destination stations, receives data transmitted over at least one spatial stream allocated to the first station in MU-MIMO transmission.

A method of selectively providing MIMO transmission/reception in a WLAN system includes using a TSPEC reservation and signaling mechanism to instantiate and tear down, dynamically, multi-channel operation in a WLAN; providing an inference algorithm to determine the minimum number of channels required to establish a TSPEC using a MIMO WLAN system; providing specific channel parameters as parameters to be negotiated in the TSPEC; providing frame exchange sequences to be used in Enhanced Distributed Coordinated Access contention based access and to be used in polled access; and providing a mechanism wherein an access point makes a decision as to whether to admit MIMO functionality on a given link, wherein a “link” is a set of communications between two specific WLAN stations.

In performing SVD-MIMO transmission, a set-up procedure is simplified while assuring a satisfactory decoding capability with a reduced number of antennas. A transmitter estimates channel information based on reference signals sent from a receiver, determines a transmit antenna weighting coefficient matrix based on the channel information, calculates a weight to be assigned to each of components of a multiplexed signal, and sends, to the receiver, training signals for respective signal components, the training signals being weighted by the calculated weights. On the other hand, the receiver determines a receive antenna weighting coefficient matrix based on the received training signals.

A transmitting device comprises a plurality of distributed transceivers, a baseband processor and a network management engine. Data streams are generated at baseband by the baseband processor. Diversity coding such as space-time coding may be performed over the generated data streams in the baseband. The transmitting device concurrently transmits each of the coded streams in a same radio frequency (RF) band to a receiving device over the entire distributed transceivers through associated antennas. When needed, the network management engine may identify one or more auxiliary devices providing available transceivers and antenna beamformers to the transmitting device for sharing. Beam patterns and antenna orientations may be determined for associated antennas of the available transceivers for the transmitting device. Each of the coded data streams in the same radio frequency band may be transmitted to the receiving device over the entire available transceivers for the transmitting device through the associated antennas.

The invention relates to the field of communication, and discloses a method and device for configuring a DMRS (demodulation reference signal) scrambling code sequence so as to reduce signal interference between UE (user equipment) adopting DMRS multiplexing and guarantee the signal demodulation performance of UE. In the method, a base station refers to the current application scene, and indicates the initial value configuration of the downlink DMRS scrambling code sequence used by single UE or UE group in current transmission through a signaling so as to ensure that the inter-cell or in-cell UE can flexibly perform MU (multiple -user)-MIMO (multiple input multiple output) multiplexing, thereby reducing the mutual interference between the multiplexing UE and guaranteeing the signal demodulation performance of the UE; and meanwhile, the overhead of a PDCCH (physical downlink control channel) is reduced through joint coding, the configuration of the same DMRS scrambling code sequence for the UE of different cells can be flexibly supported, and the configuration of different DMRS scrambling code sequences for the UE of the same cell can be flexibly supported, thereby supporting high-rank MU-MIMO transmission and effectively increasing the system throughput.