Abstract: A method performed by a processing apparatus of a cell-free communication system that includes a plurality of access points (APs) is provided. The method includes: transmitting, to a wireless device via a master AP among one or more APs included in a cluster associated with the wireless device, measurement information for the wireless device to determine a measurement target AP for which the wireless device measures a channel state; and receiving, as a response to the measurement information, channel state information indicating the channel state to the measurement target AP, via the master AP.

Abstract: The method includes: executing, when first APs that are changed from a cluster AP to a non-cluster AP due to a change of a cluster occurs, first processing on processing target APs including the first APs and a second AP that is the non-cluster AP satisfying a predetermined condition in relation to the first APs, and thereby determining, as an operation mode of the processing target APs. The first processing includes: selecting one first processing target AP from the processing target APs, and determining a downstream-only mode as the operation mode of the one first processing target AP, and determining a upstream-only mode or a sleep mode as the operation mode of a second processing target AP that is different from the one first processing target AP and is among the processing target APs.

Abstract: Novel channel estimation techniques that can be performed solely in the analog domain are provided. The techniques use continuous analog channel estimation (CACE), periodic analog channel estimation (PACE), and multiantenna frequency shift reference (MAFSR). These techniques provide sufficient channel knowledge to enable analog beamforming at the receiver while significantly reducing the estimation overhead. These schemes involve transmission of a reference tone of a known frequency, either continuously along with the data (CACE, MAFSR) or in a separate phase from data (PACE). Analysis of the methods show that sufficient receiver beamforming gain can be achieved in sparse channels by building the beamformer using just the amplitude and phase estimates of the reference tone from each receiver antenna.

Abstract: A flexible implantable electrode array is disclosed, comprising: a shank formed from a flexible polymer material. In an example embodiment, the shank comprises: a waveguide; and a number of chipsets disposed in the shank along the length of the shank, wherein each chipset is configured to measure neural activity in tissue surrounding the shank near the respective chipset, and to communicate signals representative of the measured neural activity via the waveguide. A method for powering and receiving neuronal information from a flexible implantable electrode array comprises: wirelessly communicating power and commands from a backplane to a plurality of chipsets disposed along the length of a shank via a waveguide disposed within the shank; monitoring neural activity proximate each chipset and sending a signal representative of said neural activity from the corresponding chipset transceiver to the backplane via the waveguide.

Abstract: Novel channel estimation techniques that can be performed solely in the analog domain are provided. The techniques use continuous analog channel estimation (CACE), periodic analog channel estimation (PACE), and multiantenna frequency shift reference (MAFSR). These techniques provide sufficient channel knowledge to enable analog beamforming at the receiver while significantly reducing the estimation overhead. These schemes involve transmission of a reference tone of a known frequency, either continuously along with the data (CACE, MAFSR) or in a separate phase from data (PACE). Analysis of the methods show that sufficient receiver beamforming gain can be achieved in sparse channels by building the beamformer using just the amplitude and phase estimates of the reference tone from each receiver antenna.

Abstract: A method may include receiving radar data from a plurality of TX-RX pairs (TRPs); generating a plurality of first ellipses representing a first portion of the received radar data; determining a blocking likelihood at a point of intersection between the plurality of first ellipses; generating a new or additional ellipse representing a second portion of the received radar data; and updating, based on generating the new or additional ellipse, the blocking likelihood at the point of intersection between the first plurality of ellipses.

Abstract: The present disclosure generally relates to localization and, more particularly, to remote localization and radio-frequency identification using a combination of structural and antenna mode scattering responses. A method and system include receiving location data of an object from a plurality of transmitter-reader pairs (TRPs); generating a plurality of first ellipses representing the received location data; determining blocking likelihoods at points of intersection between the plurality of first ellipses; generating additional ellipses representing additional location data received from additional TRPs; and updating the blocking likelihoods at points of intersection between the plurality of first ellipses and the additional ellipses.

Abstract: A method and apparatus is disclosed herein for transmitting information in massive MIMO system. In one embodiment, the apparatus comprises a plurality of antenna elements; a baseband processor; a plurality of radio-frequency (RF) chains coupled to the baseband processor; a plurality of switches coupled to the plurality of RF chains, wherein positions of switches in the plurality of switches being determined by instantaneous channel state information; a radio-frequency (RF) preprocessor coupled between the plurality of switches and the plurality of antenna elements, the RF preprocessor to apply a preprocessing matrix to signals, elements of the preprocessing matrix being adjusted as a function of average channel state information, and wherein the positions of the switches and elements of the preprocessing matrix are jointly chosen, and wherein the preprocessing matrix is chosen based on a metric related to expected performance obtained from at least one channel realization.

Abstract: A single wireless slave node may be in a timing virtual network (TVN) with neighboring wireless slave nodes. The single wireless slave node may store information indicative of the identity, link propagation delay, and channel signature of each of its neighboring wireless slave nodes. The single wireless slave node may repeatedly update a timing estimate based on the stored information and by performing a physical layer fast reference signal broadcast transmission and reception.

Abstract: A method and apparatus is disclosed herein for transmitting information in massive MIMO system. In one embodiment, the apparatus comprises a plurality of antenna elements; a baseband processor; a plurality of radio-frequency (RF) chains coupled to the baseband processor; a plurality of switches coupled to the plurality of RF chains, wherein positions of switches in the plurality of switches being determined by instantaneous channel state information; a radio-frequency (RF) preprocessor coupled between the plurality of switches and the plurality of antenna elements, the RF preprocessor to apply a preprocessing matrix to signals, elements of the preprocessing matrix being adjusted as a function of average channel state information, and wherein the positions of the switches and elements of the preprocessing matrix are jointly chosen, and wherein the preprocessing matrix is chosen based on a metric related to expected performance obtained from at least one channel realization.

Abstract: A single wireless slave node may be in a timing virtual network (TVN) with neighboring wireless slave nodes. The single wireless slave node may store information indicative of the identity, link propagation delay, and channel signature of each of its neighboring wireless slave nodes. The single wireless slave node may repeatedly update a timing estimate based on the stored information and by performing a physical layer fast reference signal broadcast transmission and reception.

Abstract: A computer implemented method selects antennas in a multiple-input, multiple-output wireless local area network that includes multiple stations, and each station includes a set of antennas. Multiple consecutively transmitted sounding packets are received in a station. Each sounding packet corresponds to a different subset of the set of antennas. A channel matrix is estimated from the multiple consecutively transmitted sounding packets, and a subset of antennas is selected according to the channel matrix.

Abstract: A computer implemented method selects antennas in a multiple-input, multiple-output wireless local area network that includes multiple stations, and each station includes a set of antennas. Multiple consecutively transmitted sounding packets are received in a station. Each sounding packet corresponds to a different subset of the set of antennas. A channel matrix is estimated from the multiple consecutively transmitted sounding packets. A frame including a high throughput (HT) control field is sent to initiate a selecting of antennas, and a subset of antennas is selected according to the channel matrix.

Abstract: A method selects antennas in a multiple-input, multiple-output (MIMO) wireless local area network (WLAN) that includes a plurality of stations, and each station includes a set of antennas. Plural consecutive packets, received at a station, include plural consecutive sounding packets. Each sounding packet corresponds to a different subset of the set of antennas, and at least one of the plural consecutive packets includes a high throughput (HT) control field including a signal to initiate antenna selection and a number N indicative of a number of sounding packets which follow the at least one packet including the HT control field and which are to be used for antenna selection. A channel matrix is estimated based on a characteristic of the channel as indicated by the received N sounding packets, and a subset of antennas is selected according to the channel matrix. Station and computer program product embodiments include similar features.

Abstract: A base station transmits a set of sounding requests to a set of mobile station (MS) in a cell, using a set of beams, wherein there is one beam for each sounding request. Qualities of sounding signals transmitted by the set of MSs in response to receiving the sounding request are measured, and the set of MSs are grouped into subsets according to the qualities, wherein there is one subset of MSs associated with each beam.

Abstract: A method transmits an L bit packet in a relay network including a source node, a relay node and a destination node. The source node partitions the packet into first fragment of ?L bits and a second fragment of (1??) bits. The first fragment is transmitted from the source node to the relay node at a first data rate during a first phase. The second fragment is transmitted from the source node to the destination node at a second data rate during a second phase while the first fragment is retransmitted from the relay node to the destination node at a third data rate.

Abstract: A network includes a master node (master) and a set of slave nodes (slaves). The network uses orthogonal frequency-division multiplexing (OFDM) and time division multiple access (TDMA) symbols on sub-carriers. During a first downlink transmission from the master to the set of slaves using downlinks and all of the sub-carriers, a broadcast polling packet including data packets for each slave and sub-carrier assignments for the slaves is broadcast. Each slave transmits simultaneously to the master using uplinks and the assigned sub-carriers, a first response packet after receiving the broadcast polling packet. The master then broadcasts using the downlinks and all of the sub-carriers, a group acknowledgement packet, wherein the broadcast polling packet, the response packet, and the group acknowledgement packet include one superframe in one communication cycle, and wherein the broadcasting on the downlinks and the transmitting on the uplinks are disjoint in time.

Abstract: A method transmits a sequence of symbols in a multiple-input multiple-output (MIMO) network including a transmitter having a set of transmit antennas and a receiver having a set of receive antennas. The sequence of symbols is represented by a vector S=[S1 S2 S3 S4]T of individual symbols, where T is a transpose operator. The individual symbols are transmitted as a transmit matrix S = [ S 1 - S 2 * S 1 - S 2 * S 2 S 1 * S 2 S 1 * S 3 - S 4 * - S 3 S 4 * S 4 S 3 * - S 4 - S 3 * ] , where * is a complex conjugate, and wherein each column of the matrix S represents the symbols transmitted at each transmission interval, and subscripts index the set of transmit antennas.

Abstract: A method transmits a block of symbols in a multiple-input multiple-output (MIMO) network including a transmitter having a set of transmit antennas and a receiver having a set of receive antennas. A block of symbols is coded with a first code to generate a first block, which is transmitted and received. If a decoding of the first block is incorrect, then block of symbols is coded with the first code and then a second code different than the first code to generate a second block. The second block is transmitted, received and combined with the first block to recover the block of symbols.

Abstract: A method and network communicate packets by assigning, in each one of a set of multiple transmitters, a power level to a packet to be transmitted during a time interval. The power level is selected from a set of power levels available for the set of multiple transmitters. The power levels in the set range from highest to lowest. There is one packet for each transmitter such that there is a set of packets to be transmitted during the time interval. The set of packets is transmitted concurrently during the time interval to enable decoding of at least one of the packets in the set of packets during the time interval.