公开(公告)号：WO2019023036A1

公开(公告)日：2019-01-31

申请号：PCT/US2018/042824

申请日：2018-07-19

Applicant: HUGHES NETWORK SYSTEMS, LLC

Inventor： VASAVADA, Yash ,  RAVISHANKAR, Channasandra ,  CORRIGAN, John ,  ZAKARIA, Gaguk ,  HUANG, Xiaoling

IPC: H04B7/185 ,  H04B7/204

Abstract: A system and method for estimating calibration parameters and locating a Calibration Earth Station (CES) is described. The method may be performed offline. The method includes: providing LxM pilot signal measurements in a matrix R from L CESs and the M feed elements, wherein the matrix R comprises a set of channel coefficients c = {c1, c2,..., cM}, and k = {k1, k2,..., kL} perturbations; linking a subset of channel coefficients {c1, c2,..., cM} using each of the L CESs; and estimating a relative estimate of the k = {kl, k2,...,kL} perturbations across the L CESs by using each of the L CESs as a bridging element. In the method, the bridging element provides a strong pilot signal for at least two of the L CESs. A set of criteria for determining locations of CESs have been described. A set of desirable properties for the solution set of L CESs have been disclosed. A combination of inner loop and outer loop methods for determining the final set of optimal locations have been described.

公开(公告)号：WO2016205765A1

公开(公告)日：2016-12-22

申请号：PCT/US2016/038260

申请日：2016-06-17

Applicant: HUGHES NETWORK SYSTEMS, LLC

Inventor： RAVISHANKAR, Channasandra ,  CORRIGAN, John ,  GOPAL, Rajeev ,  VASAVADA, Yash ,  JONG, James ,  BENAMMAR, Nassir ,  ZAKARIA, Gaguk ,  NOERPEL, Anthony ,  RAMCHANDRAN, Harish ,  HUANG, Xiaoling

IPC: H04W4/00

CPC classification number: H04W84/06 ,  H04B7/18563 ,  H04W84/042 ,  H04W88/085 ,  H04W92/045

Abstract: A satellite system comprises LEO satellites and MEO satellites, and a control plane protocol architecture. The PHY, MAC, MAC/RLC and RRC layers are optimized for satellite environment. When the satellites are not processing satellites, eNB functions are implemented in a satellite gateway, and, when the satellites are processing satellites, protocol architecture in the control plane differ from LTE, as follows: PHY layer is moved to the communicating LEO/MEO satellite on the user link, MAC/RLC, RRC and PDCP are be located in satellite or gateway depending on satellite complexity, and the need to have mesh connectivity between UTs. When the RRC is implemented in the satellite, the RRC is divided into RRC-Lower and RRC-Upper layers. The RRC-L is satellite-based, and handles UT handover. The RRC-U is eNB-based, and handles resource management functions. The RRC-U communicates with the PDCP layer in the eNB to configure security, header and data compression.

Abstract translation: 卫星系统包括LEO卫星和MEO卫星，以及控制平面协议架构。 PHY，MAC，MAC / RLC和RRC层针对卫星环境进行了优化。 当卫星不处理卫星时，eNB功能在卫星网关中实现，并且当卫星处理卫星时，控制平面中的协议架构与LTE不同，如下所述：PHY层被移动到通信的LEO / MEO卫星 在用户链路上，根据卫星复杂度，MAC / RLC，RRC和PDCP位于卫星或网关中，并且需要在UT之间具有网格连接。 当在卫星中实现RRC时，RRC被划分为RRC-Lower和RRC-Upper层。 RRC-L是基于卫星的，并且处理UT切换。 RRC-U是基于eNB的，并且处理资源管理功能。 RRC-U与eNB中的PDCP层进行通信，以配置安全性，头部和数据压缩。

公开(公告)号：WO2020132201A1

公开(公告)日：2020-06-25

申请号：PCT/US2019/067407

申请日：2019-12-19

Applicant: HUGHES NETWORK SYSTEMS, LLC

Inventor： RAVISHANKAR, Channasandra ,  CORRIGAN, John ,  ARUR, Deepak

IPC: H04B7/185

Abstract: Embodiments disclosed herein relate generally to techniques for mitigating blockages associated with satellite systems. More specifically, techniques disclosed herein, describe solutions for minimizing service interruption during satellite handover. One or more blockages associated with one or more user terminals that connect to a satellite system may be determined by various means. Utilizing those blockages, handover times for the one or more user terminals may be determined such that service interrupts may be minimized.

公开(公告)号：WO2018106965A1

公开(公告)日：2018-06-14

申请号：PCT/US2017/065186

申请日：2017-12-07

Applicant: HUGHES NETWORK SYSTEMS, LLC

Inventor： RAVISHANKAR, Channasandra ,  CORRIGAN, John ,  ZAKARIA, Gaguk

IPC: H04W36/00

Abstract: An apparatus for establishing communication between a base station and different generation terminals includes a multi-protocol stack capable of processing user traffic received from different generation terminals. The apparatus also includes a common physical layer that receives user traffic from different generation terminals and identifies the generation of the terminal sending the user traffic. The user traffic is then processed and routed based on the terminal generation. Traffic can be prioritized across current and legacy terminal types based on a variety of factors.

公开(公告)号：WO2019144078A1

公开(公告)日：2019-07-25

申请号：PCT/US2019/014421

申请日：2019-01-21

Applicant: HUGHES NETWORK SYSTEMS, LLC

Inventor： ARUR, Deepak ,  RAVISHANKAR, Channasandra ,  BENAMMAR, Nassir ,  BARNETT, Charles ,  CORRIGAN, John

IPC: H04W36/24 ,  H04W40/18 ,  H04W36/30 ,  H04B7/185

Abstract: A method for prediction of UT handovers in a satellite communications network is provided. Optimal characteristics regarding the beams of satellites and regarding a one UT are determined. For each of a plurality of the satellite beams, for each of a plurality of instants of time t n , an estimated signal strength as seen at the UT is determined, wherein each estimated signal strength is determined based on the optimal at the respective time t n . A next instant of time t m is determined at which the estimated signal strength for a candidate beam that is within the view of the UT is greater than or equal to the estimated signal strength for the satellite beam that is currently servicing the UT. A handover of the UT, at the time t m , from the satellite beam that is currently servicing the one UT to the candidate beam is determined.

公开(公告)号：WO2019046090A1

公开(公告)日：2019-03-07

申请号：PCT/US2018/047689

申请日：2018-08-23

Applicant: HUGHES NETWORK SYSTEMS, LLC

Inventor： RAVISHANKAR, Channasandra ,  HUANG, Xiaoling ,  BENAMMAR, Nassir ,  GOPAL, Rajeev ,  CORRIGAN, John

IPC: H04B7/185

Abstract: A method for networked scheduling is disclosed. The method includes: providing a gateway; a plurality of channels assigned to a color reuse scheme including colors, wherein some of the plurality of channels assigned to one of the colors comprise a set of co-channels; associating the set of co-channels with the gateway; generating a traffic pattern for the set of co-channels for an upcoming allocation slot; determining a channel state of each co-channel in the set of co-channels per the traffic pattern; and setting a Modulation and Coding scheme (MODCOD) of each co-channel in the set of co-channels based on the respective channel state.

公开(公告)号：WO2018217824A1

公开(公告)日：2018-11-29

申请号：PCT/US2018/033982

申请日：2018-05-22

Applicant: HUGHES NETWORK SYSTEMS, LLC

Inventor： RAVISHANKAR, Channasandra ,  CORRIGAN, John

IPC: H01Q1/28 ,  H04B7/185 ,  H04B10/00 ,  H04B10/118

Abstract: Approaches for ground-based beamforming for a very high throughput wireless communications system employing an airborne platform that generates a beam pattern via a multi-element antenna are provided. A beamformer includes a number of beamforming processors based on a frequency reuse scheme of the communications system. Each beamforming processor processes only the beam signals that are associated with a respective one of the frequencies of the reuse scheme, and thereby generates a component element signal for each of the elements of the array antenna that is associated with the respective frequency of that processor. Each beamforming processor applies a matrix of complex weights that is configured such that a composition of the component element signals for each antenna element facilitates the transmission of the element signals by the airborne platform to produce the beam pattern.

公开(公告)号：WO2014179367A1

公开(公告)日：2014-11-06

申请号：PCT/US2014/035964

申请日：2014-04-29

Applicant: HUGHES NETWORK SYSTEMS, LLC

Inventor： RAVISHANKAR, Channasandra ,  ZAKARIA, Gaguk ,  BENAMMAR, Nassir ,  CORRIGAN, John

IPC: H04W12/04

CPC classification number: H04L9/14 ,  H04L9/0819 ,  H04L9/0841 ,  H04L63/0428 ,  H04L2209/24 ,  H04L2209/80 ,  H04W12/02 ,  H04W12/04 ,  H04W76/12 ,  H04W84/06

Abstract: An approach for improved security protocols in a mobile satellite system is provided. A remote terminal performs a key establishment function, including determination of a first encryption key for encrypting data for transmission over the satellite communications channels, and determination of an authentication key for authenticating entities communicating over the communications channels. The remote terminal receives a security mode command including a key indicator, and determines a second encryption key for enhanced session data security over communications channels. The second encryption key is determined based on the key indicator and a key generation algorithm. The remote terminal further determines a key indicator response and transmits a security mode complete command including the key indicator response to a satellite base station subsystem (SBSS). The key indicator response is constructed for the SBSS to determine the second encryption key based on the key indicator response and a key generation algorithm.

Abstract translation: 提供了一种用于改进移动卫星系统中的安全协议的方法。 远程终端执行密钥建立功能，包括确定用于加密卫星通信信道传输的数据的第一加密密钥，以及用于认证通过通信信道通信的实体的认证密钥的确定。 远程终端接收包括密钥指示符的安全模式命令，并且通过通信信道确定增强的会话数据安全性的第二加密密钥。 第二加密密钥是基于密钥指示符和密钥生成算法确定的。 远程终端还确定密钥指示符响应，并向卫星基站子系统（SBSS）发送包括密钥指示符响应的安全模式完成命令。 构建关键指示符响应，用于SBSS基于密钥指示符响应和密钥生成算法来确定第二加密密钥。