The present technology relates to a communication apparatus and a communication method that permit realization of more reliable communication. Provided is a communication apparatus that includes a control section that performs control such that plural aggregated subframes are sent in a predetermined sequence for each frame included in each of spatially multiplexed streams when a frame is sent to another communication apparatus as plural spatially multiplexed streams. The present technology is applicable, for example, to a communication apparatus included in a wireless LAN system.

Spatial redistributors and methods of redistributing signals in accordance with various embodiments of the invention are illustrated. One embodiment includes an array of channels configured to receive and retransmit a signal, where each of a plurality of independently operating channels in the array includes: at least one antenna element; an RF chain configured to apply at least a time delay to the received signal prior to retransmission; control circuitry configured to control the time delay applied to the received signal by the RF chain; and a reference oscillator. In addition, the array of channels is configured to redirect a signal received from a first set of directions for retransmission in a second set of directions; and the control circuitry of the channels in the array of channels coordinates the time delays applied to the received signal across the array of channels to control the wave front of the retransmitted signal.

A method for optimizing user equipment wireless localization using K reconfigurable intelligent surfaces reflecting signal(s) transmitted between a base station and the user equipment, the method including, whatever an a priori position of the user equipment selecting at least one reconfigurable intelligent surface to activate among the K reconfigurable intelligent surfaces, determining phases of elements of the at least one reconfigurable intelligent surface, by minimizing a predetermined cost function, depending on the a priori position, and accounting for a predetermined position error bound of the user equipment, while ensuring that at most K reconfigurable intelligent surfaces are selected, ensuring that the minimum Euclidian distance between two consecutive selected reconfigurable intelligent surfaces of a predetermined configuration, is strictly higher than a predetermined value limiting interference between additional multipath components generated by the at least one reconfigurable intelligent surface.

Methods, systems, and devices for wireless communications are described. A control resource set (CORESET) may be configured to support multiple transmission configuration indicator (TCI) state control channels. Space division multiplexing (SDM) may be implemented to enable multi-TCI states by using multiple ports and layers. A certain layer and demodulation reference signal (DMRS) port may be associated with a certain TCI state. For orthogonal ports, resources elements (REs) may be assigned such that a first set of REs are assigned to the first DMRS port and a second set of REs are assigned to the second port. The multiple DMRS ports may be code division multiplexed (CDM'd) within an RE such that multiple DMRS ports may be associated with the same RE. For non-orthogonal ports, the same RE may be used for multiple TCI states, where scrambling sequences may be applied to DMRSs associated with the TCI states.

An orthogonal frequency-division multiplexing (OFDM) base station operative to transmit a sequence of spatially multiplexed OFDM signals simultaneously using at least two separate twisted pairs, in which each of the OFDM signals is modulated by a plurality of sub-carriers. At least two converters are connected to the OFDM base station using the at least two twisted pairs, respectively, in which each of the converters, and simultaneously with the other converters, is configured to receive each of the OFDM signals from the OFDM base station using the respective twisted pair, up-convert the OFDM signal into a radio-frequency (RF) band, and re-transmit wirelessly the OFDM signal, in conjunction with the RF band, from at least one antenna associated with each converter, thereby together creating a macro-diversity effect in conjunction with the spatially multiplexed OFDM signals.

A signal generation method is used in a transmission device that transmits a plurality of transmission signals from a plurality of antennas at the same frequency and at the same time, in the case where larger power change is performed on a first transmission signal than on a second transmission signal during generation process of the first transmission signal and the second transmission signal, the first transmission signal and the second transmission signal are mapped before the power change such that a minimum Euclidian distance between possible signal points for the first signal is longer than a minimum Euclidian distance between possible signal points for the second signal.

The present disclosure provides communication apparatus and communication method for channel estimation. The communication apparatus comprises a transmitter, which in operation, transmits a physical layer protocol data unit (PPDU) to one or more other communication apparatus in a multiple-input multiple-output (MIMO) wireless network, the PPDU including a long training field (LTF) that facilitates the one or more other communication apparatus to estimate respective channels for respective communications with the communication apparatus; and a controller, which in operation, establishes the number of LTF symbols (N.sub.LTF) for generating the LTF in the PPDU, wherein the N.sub.LTF depends on a maximum value (N.sub.STSMAX) of the number of space-time streams for each resource unit (RU) in the PPDU.

Methods, media, and systems are provided for restricting an uplink Multiple Input Multiple Output (MIMO) assignment based on fading, battery data, or location data associated with a user device in an mmWave system. Fading data, location data, or battery data is received from one or more user devices. Based on the received data, a determination is made using the data received (e.g., determining the battery data of the user device is below a threshold or determining the location of the user device). In response, the assignment of the user device to an uplink MIMO layer of available MIMO layers is restricted. The restricted uplink MIMO layer is a higher MIMO layer than another MIMO layer of the available MIMO layers. In response to restricting the assignment, the user device may be assigned to an available MIMO layer that is a lower MIMO layer than the restricted MIMO layer.

Apparatuses, methods, and systems are disclosed for preparing channel state information (“CSI”). One apparatus includes a processor and a transceiver configured to communicate with a base unit over a radio access network using at least one transmission layer and determining a total number of non-zero coefficients over a set of layers. The processor encodes the total number of non-zero coefficients by selecting a codeword from a plurality of candidate codewords in which the selected single codeword identifies the total number of non-zero coefficients to the base unit. The processor prepares CSI, where the CSI comprises the selected single codeword encoding the total number of non-zero coefficients and the transceiver transmits the CSI to the base unit.

A transmission device includes: a weighting synthesizer that generates a first precoded signal and a second precoded signal; a first pilot inserter that inserts a pilot signal into the first precoded signal; a phase changer that applies a phase change of i×Δλ to the second precoded signal, where i is a symbol number and an integer that is greater than or equal to 0; an inserter that inserts a pilot signal into the phase-changed second precoded signal; and a phase changer that applies a phase change to the phase-changed and pilot-signal-inserted second precoded signal. Δλ satisfies π/2 radians<Δλ<π radians or π radians<Δλ<3π/2 radians.