Abstract:
A system and method for uplink multi-antenna power control in a communications system are provided. A method for user equipment operations includes determining a transmit power level for transmit antennas of the user equipment having at least two transmit antennas, and setting a power amplifier output level for each of the at least two transmit antennas in accordance with a respective transmit power level.
Abstract:
Techniques and devices for antenna selection in a multiple-input-multiple- output (MIMO) system, in which communication is between a transmitter having a first plurality of radio-frequency (RF) chains coupled to a first plurality of antennas and a receiver having a second plurality of RF chains coupled to a second plurality of antennas, are provided. Techniques include receiving consecutive sounding packets each have a training symbol and that collectively sound a full-size channel for the MIMO system. A sub-channel estimate for each sounding packet can then be determined based on various factors, such as a known power level rule and gain factor. Scaling factors may be applied to each of these sub-channel estimates to produce a scaled sub-channel estimates.
Abstract:
Systems and methods of convergence beamforming are disclosed. One method embodiment, among others, comprises receiving N data streams (315A, 315B) from at least N+l antennas (205-205D), where N is an integer greater than 1; determining signal characteristics (310A, 310B) of each received data stream (315A, 315B); and adjusting the signal characteristics of N data streams to be transmitted based on the determined signal characteristics (310A, 310B) of the received N data streams. The convergence beamforming may be achieved by the orthogonalization of received multipath channel vectors (310A, 310B). The transmission signals from a station (130) are adjusted corresponding to the channel characteristics of the signals received by station (130).
Abstract:
Embodiments of the disclosure relate to selective multichannel amplification in a distributed antenna system (DAS), In this regard, a remote antenna unit (RAU) in the DAS receives downlink digital signals associated with downlink channels having respective downlink channel bandwidths. The RAU digitally scales the downlink digital signals based on respective digital scaling factors to generate sealed downlink digital signals having a substantially equal channel power density in the downlink channels. By digitally scaling the downlink digital signals to provide the substantially equal channel power density in the downlink channels, it is possible to provide substantially uniform radio frequency (RF) coverage range across the downlink channels, thus helping to improve overall RF coverage and user experience in a coverage area of the RAU.
Abstract:
Systems and methodologies are described that facilitate constructing unitary matrices that may be utilized in linear precoding for multiple-input multiple-output (MIMO) wireless communication systems. Each unitary matrix may be generated by combining (e.g., multiplying) a diagonal matrix with a Discrete Fourier Transform (DFT) matrix. The unitary matrices may be utilized to provide feedback related to a channel and/or control transmission over a channel based upon obtained feedback.
Abstract:
Systems and methodologies are described that facilitate constructing unitary matrices that may be utilized in linear precoding for multiple-input multiple-output (MIMO) wireless communication systems. Each unitary matrix may be generated by combining (e.g., multiplying) a diagonal matrix with a Discrete Fourier Transform (DFT) matrix. The unitary matrices may be utilized to provide feedback related to a channel and/or control transmission over a channel based upon obtained feedback.
Abstract:
Techniques for scheduling flows and links for transmission are described. Each link is an oriented source-destination pair and carries one or more flows. Each flow may be associated with throughput, delay, feedback (e.g., acknowledgments (ACKs)) and/or other requirements. A serving interval is determined for each flow based on the requirements for the flow. A serving interval is determined for each link based on the serving intervals for all of the flows sent on the link. Each link is scheduled for transmission at least once in each serving interval, if system resources are available, to ensure that the requirements for all flows sent on the link are met. The links are also scheduled in a manner to facilitate closed loop rate control. The links are further scheduled such that ACKs for one or more layers in a protocol stack are sent at sufficiently fast rates.
Abstract:
La présente invention se rapporte à un procédé d'émission simultanée de flux destiné à un système MIMO multi utilisateurs à N T antennes d'émission et N R k antennes de réception par récepteur associé à un utilisateur définissant Q k =min (N Rk ,N T ) flux de données transportés par un canal de transmission par utilisateur pouvant transporter pour K utilisateurs un nombre maximal (Q) comprenant : une étape d'initialisation d'une liste H s ( H s = h 1 ) de canaux de transmission virtuels basée sur la sélection d'un premier flux, et comprenant de manière récursive jusqu'à atteindre les Q flux : une étape de construction d'une matrice de projection ( P i ⊥ ) sur un espace complémentaire aux canaux de transmission virtuels correspondant aux flux sélectionnés, une étape de construction d'une matrice projetée (H k ⊥ ) des canaux de transmission projetés basée sur une projection ( H k ⊥ = H k P i ⊥ ) de tous les canaux de transmission au moyen de la matrice de projection ( P i ⊥ ), - une étape de sélection, basée sur une décomposition en valeurs propres (H k ⊥ =U k ⊥ S k ⊥ V k ⊥ N ) de la matrice projetée ( H k ⊥ ) permettant d'écrire la matrice projetée ( H k ⊥ ) sous la forme d'un produit d'une matrice gauche unitaire, d'une matrice diagonale contenant les valeurs propres et de l'hermitien d'une matrice droite unitaire, d'un meilleur flux correspondant au canal de transmission projeté ayant la plus grande valeur propre, - une étape de mise à jour de la liste H s ( H s = [ H s T , h i T ] T ) en ajoutant le canal de transmission virtuel associé au flux sélectionné.
Abstract translation:本发明涉及一种同时发送旨在用于具有NT个发送天线的多用户MIMO系统的流的方法,并且每个每个接收者的NR k个接收天线与定义由每个用户的传输信道传输的Q k = min(NR k,NT)个数据流的用户相关联 其可以为K个用户传送最大数量(Q),包括:初始化虚拟传输信道的列表H s(H s = h1)的步骤,所述列表基于第一流的选择,并且包括在递归中 方式直到Q流:构建用于映射到与所选择的流相对应的虚拟传输信道互补的空间上的投影矩阵(P i')的步骤,构建所述Q流的投影矩阵(H k?)的步骤 所述矩阵基于所述投影矩阵(P i?)的所有传输信道的投影(H k?= H k P i?), - 基于特征值分解的选择步骤 (H k?= Uk? S k(V k) N),使得可以以单位左矩阵的乘积的形式将包含特征值和单位的隐性的对角矩阵的投影矩阵(H k?)写入 对应于具有最大特征值的投影传输信道的更好流的右矩阵; - 通过将与所述特征值相关联的虚拟传输信道相加的步骤来更新列表H s(H s = [H s T,hi T] T) 选择流。