公开(公告)号：WO2014149062A1

公开(公告)日：2014-09-25

申请号：PCT/US2013/033594

申请日：2013-03-22

Applicant: HITACHI, LTD. ,  GAO, Long ,  GAUR, Sudhanshu ,  ACHARYA, Joydeep

Inventor： GAO, Long ,  GAUR, Sudhanshu ,  ACHARYA, Joydeep

IPC: H04W4/00

CPC classification number: H04L5/0092 ,  H04L5/0051 ,  H04L5/0085 ,  H04L5/14 ,  H04W4/021 ,  H04W4/027

Abstract: Example implementations described herein are directed to systems and methods of using the Demodulation Reference Signal (DMRS) in a manner to reduce the DMRS overhead in the Long Term Evolution (LTE)-Advanced downlink. In example implementations, an enhanced node B (eNodeB) transmits the DMRS only in some of the Resource Blocks (RBs) that are scheduled for a User Equipment (UE). The frequency of which the DMRS is transmitted is determined by the eNodeB based on one or more attributes of the UE and signaled to the UE via Radio Resource Control (RRC) signaling. At the UE receiver, the Physical Downlink Shared Channel (PDSCH) is demodulated based on the received DMRS configuration. Example implementations can thereby reduce the DMRS overhead by avoiding DMRS transmission in some subframes.

Abstract translation: 本文描述的示例实施例涉及以减少长期演进（LTE）高级下行链路中的DMRS开销的方式使用解调参考信号（DMRS）的系统和方法。 在示例实现中，增强节点B（eNodeB）仅在为用户设备（UE）调度的一些资源块（RB）中发送DMRS。 发射DMRS的频率由eNodeB根据UE的一个或多个属性确定，并通过无线电资源控制（RRC）信令向UE发送信号。 在UE接收机处，物理下行链路共享信道（PDSCH）根据所接收的DMRS配置进行解调。 因此，示例性实现可以通过避免某些子帧中的DMRS传输来减少DMRS开销。

公开(公告)号：WO2015116070A1

公开(公告)日：2015-08-06

申请号：PCT/US2014/013678

申请日：2014-01-29

Applicant: HITACHI, LTD.

Inventor： MUKHERJEE, Amitav ,  GAO, Long ,  GAUR, Sudhanshu

IPC: H04W72/12

CPC classification number: H04W72/082 ,  H04L5/0053 ,  H04L5/0073

Abstract: Reliable decoding of control channels can be important in Long Term Evolution/Long Term Evolution Advanced (LTE/LTE-A) networks. Methods are provided for intercell interference coordination of control channels in LTE networks. Dense deployments of heterogeneous and small cell networks can increase interference and further degrade control channel (CC) reception. With coordination between base stations, interference to legacy or enhanced control channels can be mitigated. However, the overhead and periodicity of coordination can be dependent on the inter-eNB backhaul link quality. Implementations are provided for CC ICIC, under various backhaul quality assumptions.

Abstract translation: 控制信道的可靠解码在长期演进/长期演进高级（LTE / LTE-A）网络中是重要的。 为LTE网络中控制信道的小区干扰协调提供了方法。 异构和小型小区网络的密集部署可能会增加干扰并进一步降低控制信道（CC）接收。 通过基站之间的协调，可以减轻对传统或增强控制信道的干扰。 然而，协调的开销和周期可以取决于eNB之间的回程链路质量。 根据各种回程质量假设，为CC ICIC提供实施。

公开(公告)号：WO2015187130A1

公开(公告)日：2015-12-10

申请号：PCT/US2014/040693

申请日：2014-06-03

Applicant: HITACHI, LTD. ,  ACHARYA, Joydeep ,  AKOUM, Salam ,  GAO, Long

Inventor： ACHARYA, Joydeep ,  AKOUM, Salam ,  GAO, Long

IPC: H04B7/26

CPC classification number: H04B7/024 ,  H04B7/0617 ,  H04B7/0619 ,  H04B7/063

Abstract: Example implementations described herein are directed to systems and methods that utilize adaptive antenna arrays that include one or more antennas at the user equipment (UE) to dynamically steer the antenna response at the UE to improve system performance. The improvement is achievable in both downlink and uplink. The example implementations described herein also involve details of the associated signaling. The UE sends feedback measurement signals related to the position and orientation of the UE to the base station, wherein the base station calculates and provides antenna response parameters for the UE based on the received feedback.

Abstract translation: 本文描述的示例性实现涉及利用在用户设备（UE）处包括一个或多个天线的自适应天线阵列来动态地引导UE处的天线响应以提高系统性能的系统和方法。 下行链路和上行链路都可以实现改进。 本文描述的示例实现还涉及相关联的信令的细节。 UE向基站发送与UE的位置和取向相关的反馈测量信号，其中基站根据接收到的反馈计算并提供UE的天线响应参数。

公开(公告)号：WO2015084350A1

公开(公告)日：2015-06-11

申请号：PCT/US2013/073179

申请日：2013-12-04

Applicant: HITACHI, LTD.

Inventor： AKOUM, Salam ,  MUKHERJEE, Amitav ,  GAO, Long

IPC: H04K1/10

CPC classification number: H04K1/10 ,  H04B7/024 ,  H04B7/0617 ,  H04B7/0626 ,  H04W16/28

Abstract: Example implementations described herein are directed to operation of heterogeneous networks with dynamic reconfiguration of network parameters of a base station such as antenna tilt, to optimize the deployment of base stations and antennas in the network. In example implementations, associated user equipment and/or base stations derive a feedback consensus for estimating an optimization of one or more of the network parameters based on one or more metrics such as channel quality. Based on the one or more metrics, the feedback consensus is reached iteratively for the network parameters, and the base station is then informed of the optimized estimation of the network parameters.

Abstract translation: 本文描述的示例实现涉及具有基站的网络参数（例如天线倾斜）的动态重新配置的异构网络的操作，以优化网络中的基站和天线的部署。 在示例实现中，相关联的用户设备和/或基站基于一个或多个度量（例如信道质量）导出用于估计网络参数中的一个或多个的优化的反馈共识。 基于一个或多个度量，针对网络参数迭代地获得反馈一致性，然后基站通知网络参数的优化估计。

公开(公告)号：WO2012024122A3

公开(公告)日：2012-02-23

申请号：PCT/US2011/047192

申请日：2011-08-10

Applicant: HITACHI, LTD. ,  GAO, Long ,  ACHARYA, Joydeep

Inventor： GAO, Long ,  ACHARYA, Joydeep

IPC: H04B7/04 ,  H04B15/00 ,  H04W88/08 ,  H04W16/02

Abstract: A central base station for interference management in a distributed antenna system comprises a processor; a memory; and a frequency partition module configured to divide the remote radio heads into clusters and allocate a frequency band to each cluster. Multiple clusters use the same frequency band and groups of clusters are formed. A joint scheduler is configured, for each group, to activate at most two clusters at any given time and deactivate remaining clusters in the group, one of the at most two activated clusters being a serving cluster of the group, and to associate one or more users with the serving cluster in the group. An interference alignment module is configured to apply downlink interference alignment between the at most two activated clusters in each group to align transmit directions of all interferences between the at most two activated clusters.

公开(公告)号：WO2015152932A1

公开(公告)日：2015-10-08

申请号：PCT/US2014/032890

申请日：2014-04-03

Applicant: HITACHI, LTD

Inventor： GAO, Long ,  GAUR, Sudhanshu ,  AKOUM, Salam

IPC: H04W36/00

CPC classification number: H04W36/20 ,  H04W84/045

Abstract: Example implementations described herein are directed to the consideration of inter cell interference coordination in femto networks. The femto cells deployed in the same frequency band can interfere with each other especially in dense deployment scenarios. In particular, a CSG femto cell may cause strong interference to its neighboring non-CSG UEs (which are not allowed to connected to the CSG cell) in the downlink. Example implementations described herein can reduce the interference level experienced by those UEs and may thereby improve their throughput performance.

Abstract translation: 本文描述的示例性实现涉及毫微微网络中的小区间干扰协调的考虑。 部署在相同频带的毫微微小区可能彼此干扰，特别是在密集部署情况下。 特别地，CSG毫微微小区可能在下行链路中对其相邻的非CSG UE（其不被允许连接到CSG小区）造成强烈干扰。 本文描述的示例实现可以减少这些UE所经历的干扰水平，从而可以提高其吞吐量性能。

公开(公告)号：WO2015084334A1

公开(公告)日：2015-06-11

申请号：PCT/US2013/072882

申请日：2013-12-03

Applicant: HITACHI, LTD.

Inventor： GAO, Long ,  GAUR, Sudhanshu ,  ACHARYA, Joydeep

IPC: H04B7/00

CPC classification number: H04B7/024 ,  H04L5/00

Abstract: Example implementations are directed to small cell activation systems and methods in a LTE-Advanced network. Each small cell in a cluster turns itself on following a given period and time offset. For a particular small cell, the activation procedure is divided into two stages. In the first stage, the small cell sends a reference signal and broadcasts system information. It collects the traffic information of its associated UEs and sends the information to its neighboring cells via backhaul. The small cell does not serve any UE in this stage. Any UE that is associated to it will be handed over to one of its neighboring active cells when packets arrive. In the second stage, the small cell decides whether to turn itself on based on the collected information and feedbacks from its neighboring cells, and will serve its associated UEs if it decides to turn itself on.

Abstract translation: 示例实现涉及LTE-Advanced网络中的小小区激活系统和方法。 群集中的每个小单元都会按照给定的时间和时间偏移量自行调整。 对于特定的小单元，激活程序分为两个阶段。 在第一阶段，小小区发送参考信号并广播系统信息。 它收集其相关联的UE的业务信息，并通过回程将信息发送到其相邻小区。 在这个阶段，小小区不服务任何UE。 当分组到达时，与其相关联的任何UE将被切换到其相邻活动小区中的一个。 在第二阶段，小单元根据所收集的信息和来自其相邻小区的反馈决定是否自己开启，并且如果它决定开启自身，则将服务于其相关联的UE。

公开(公告)号：WO2014140678A1

公开(公告)日：2014-09-18

申请号：PCT/IB2013/001248

申请日：2013-03-15

Applicant: HITACHI, LTD.

Inventor： ACHARYA, Joydeep ,  GAUR, Sudhanshu ,  GAO, Long

IPC: H04W72/04

CPC classification number: H04W72/0446

Abstract: Exemplary embodiments provide techniques to properly choose an uplink/downlink (UL/DL) configuration for base stations to minimize the chances of UL DL interference while keeping the configurations aligned to traffic conditions. In one embodiment, a time division duplex (TDD) system includes an apparatus, a first base station having a first UL/DL configuration, and a second base station having a second UL/DL configuration which is not identical to the first UL/DL configuration. The apparatus comprises a processor, a memory, and a configuration determination module which is operable to: judge whether the first and second UL/DL configurations are close or not based on a preset condition; and if it is judged that the first and second UL/DL configurations are close, decide, based on the first and second UL/DL configurations, a common UL/DL configuration to be used by the first and second base stations instead of the first and second UL/DL configurations.

Abstract translation: 示例性实施例提供了适当地选择用于基站的上行链路/下行链路（UL / DL）配置以最小化UL DL干扰的机会同时保持配置与交通状况一致的技术。 在一个实施例中，时分双工（TDD）系统包括装置，具有第一UL / DL配置的第一基站和具有与第一UL / DL不同的第二UL / DL配置的第二基站 组态。 该装置包括处理器，存储器和配置确定模块，其可操作以：基于预设条件判断第一和第二UL / DL配置是否接近; 并且如果判断出第一和第二UL / DL配置接近，则基于第一和第二UL / DL配置来确定要由第一和第二基站而不是第一和第二基站使用的公共UL / DL配置 和第二UL / DL配置。

公开(公告)号：WO2014140667A1

公开(公告)日：2014-09-18

申请号：PCT/IB2013/000925

申请日：2013-03-15

Applicant: HITACHI, LTD.

Inventor： ACHARYA, Joydeep ,  GAO, Long ,  GAUR, Sudhanshu

IPC: H04W24/02 ,  H04W84/10

CPC classification number: H04W16/10 ,  H04W24/02 ,  H04W24/08 ,  H04W48/16 ,  H04W84/045

Abstract: A communications system includes a macro base station, a plurality of UEs (user equipment), a plurality of small cells, and a network through which the macro base station, the UEs, and the small cells communicate with each other, the small cells within a macro coverage area of the macro base station. The macro base station comprises a processor, a memory, and a small cell on/off module which is operable, for each small cell of the plurality of small cells, to: determine an interference metric for the small cell; if the determined interference metric meets a preset condition for the small cell, then determine a loss in signal strength to the UEs associated with the small cell caused by switching off the small cell; and judge whether to switch off the small cell based on at least one of the determined interference metric or the determined loss in signal strength.

Abstract translation: 通信系统包括宏基站，多个UE（用户设备），多个小小区以及宏基站，UE和小小区之间相互通信的网络，小区内的小小区 宏基站的宏覆盖区域。 宏基站包括处理器，存储器和小小区开/关模块，其可操作用于所述多个小小区中的每个小小区以确定所述小小区的干扰度量; 如果确定的干扰度量符合小小区的预设条件，则确定由关闭小小区导致的与小小区相关联的UE的信号强度的损失; 并且基于所确定的干扰度量或确定的信号强度的损失中的至少一个来判断是否关闭小小区。

公开(公告)号：WO2014130082A1

公开(公告)日：2014-08-28

申请号：PCT/US2013/057788

申请日：2013-09-03

Applicant: HITACHI, LTD.

Inventor： GAO, Long ,  GAUR, Sudhanshu ,  ACHARYA, Joydeep

IPC: H04W4/00

CPC classification number: H04L5/0048 ,  H04L5/0023 ,  H04L5/0082 ,  H04L5/0094

Abstract: A wireless system comprises: an eNodeB including a controller and a memory, the controller being operable, for each subframe containing PDSCH of a radio frame of a plurality of radio frames to be transmitted, each subframe having a subframe index, to select a demodulation reference signal (DMRS) pattern for DMRS transmission based on the subframe index, generate the PDSCH data with the selected DMRS pattern, and transmit the PDSCH data; and a UE including a UE controller and a UE memory, the UE controller being operable, upon receiving the PDSCH data of a subframe from the eNodeB, to identify the subframe index of the subframe, select a UE-selected DMRS pattern for channel estimation based on the subframe index, extract DMRS resource elements according to the UE-selected DMRS pattern, perform channel estimation using the extracted DMRS to obtain a channel estimate, and demodulate the PDSCH data based on the channel estimate.

Abstract translation: 一种无线系统，包括：包括控制器和存储器的eNodeB，所述控制器对于包含要发送的多个无线电帧的无线电帧的PDSCH的每个子帧可操作，每个子帧具有子帧索引，以选择解调参考 基于子帧索引的DMRS传输的信号（DMRS）模式，使用所选择的DMRS模式生成PDSCH数据，并发送PDSCH数据; 以及包括UE控制器和UE存储器的UE，所述UE控制器在从所述eNodeB接收到子帧的PDSCH数据时可操作以识别所述子帧的子帧索引，选择用于信道估计的UE选择的DMRS模式 在子帧索引上，根据UE选择的DMRS模式提取DMRS资源元素，使用提取的DMRS进行信道估计，以获得信道估计，并且基于信道估计解调PDSCH数据。