Abstract:
Machine-readable media, methods, apparatus and system for electrical downtilt adjustment in a multiple input multiple output system are disclosed. In some embodiments, an apparatus may comprise an electrical downtilt module to determine an electrical downtilt angle for an antenna port selected from a number of antenna ports based on information from an user equipment (UE); and a codebook module to select a codeword corresponding to the antenna port from a codebook and calculate a weight of an antenna array of the eNB through inputting the electronic downtilt angle into the codeword, wherein the codebook has a first number of codewords, each of the codewords having a second number of elements to represent the weight of the antenna array, and wherein each of the codewords corresponds to each of the antenna ports and each of the elements corresponds to each antenna of the antenna array.
Abstract:
According UE is configured to receive a channel state information reference signal (CSI-RS) from an evolved Universal Terrestrial Radio Access Network (E-UTRAN) Node B (eNB), determine channel state information based on the CSI-RS, and send the channel state information to the eNB. The channel state information includes a precoding matrix indicator corresponding to a first precoding matrix. The UE is also configured to receive a UE specific reference (UE-RS) signal and a physical downlink shared channel (PDSCH) signal. The UE-RS is precoded with a second precoding matrix. The UE estimates a UE-RS effective channel including the second precoding matrix based on the UE-RS and decodes data from the PDSCH signal based on an the first precoding matrix and the UE-RS effective channel.
Abstract:
In embodiments, apparatuses, methods, and storage media may be described for reducing the overhead associated with the transmission of channel training signals from an eNodeB (eNB) of a wireless network. Specifically, the eNB may receive feedback from a user equipment (UE) regarding the received signal energy of a first and second beamformed signal produced with a first and second beamforming vector, respectively. The eNB may identify, based on the feedback of the received signal energy, a signal subspace and a null subspace. The eNB may then transmit a channel training signal to the signal subspace.
Abstract:
A hybrid digital and analog beamforming device for a node operable with an antenna array is disclosed. In an example, the hybrid digital and analog beamforming device can include computer circuitry configured to: Segment antenna elements of an antenna array into at least two groups of antenna elements; map antenna ports for transmission chains to one group of the antenna elements; constrain digital precoding weights for a digital precoder for the antenna elements, where the digital precoding weight includes a digital phase and amplitude; and determine analog precoding weights for an analog precoder for the antenna elements, where the analog precoding weight includes an analog phase.
Abstract:
Techniques are described for improving handover performance in the context of UEs incorporated into unmanned aerial vehicles (UAVs, a.k.a., drones). A database is constructed that relates locations in a three-dimensional flying space to handover information that may include optimum scanning directions, optimum handover parameters, and/or optimum target cells to be monitored for possible handover.
Abstract:
A technology for an enhanced node B (eNode B) in a cellular network that is operable to determine downtilt using full dimensional (FD) multiple-input multiple-output (MIMO). A plurality of orthogonal frequency division multiple access (OFDMA) signals can be transmitted, wherein each transmitted OFDMA signal is transmitted with a selected downtilt angle from a two dimensional antenna array of the eNode B. Reference signal received power (RSRP) feedback information can be received from a UE for each of transmitted OFDMA signals at the selected downtilt angles. Received signal strength indicator (RSSI) feedback information can be received from the UE. A reference signal received quality (RSRQ) can be calculated for each of the selected antennas angles using the RSRP feedback information and the RSSI feedback information. A downtilt angle can be selected for transmitting data from the eNode B with a highest signal to interference plus noise ratio (SINR).
Abstract:
A method includes receiving at user equipment an indication of a subset of scheduling constraints for interference mitigation and cancelation and performing interference mitigation and cancelation utilizing the subset of scheduling constraints.
Abstract:
According UE is configured to receive a channel state information reference signal (CSI-RS) from an evolved Universal Terrestrial Radio Access Network (E-UTRAN) Node B (eNB), determine channel state information based on the CSI-RS, and send the channel state information to the eNB. The channel state information includes a precoding matrix indicator corresponding to a first precoding matrix. The UE is also configured to receive a UE specific reference (UE-RS) signal and a physical downlink shared channel (PDSCH) signal. The UE-RS is precoded with a second precoding matrix. The UE estimates a UE-RS effective channel including the second precoding matrix based on the UE-RS and decodes data from the PDSCH signal based on an the first precoding matrix and the UE-RS effective channel.