Hughes Network Systems, LLC

Xiaoling Huang

Channasandra S Ravishankar

John Corrigan

Yash Vasavada

John E Corrigan, Iii

Gaguk Zakaria

Nassir Benammar

Rajeev Gopal

Anthony Robert Noerpel

James Jehong Jong

Deepak Manohar Arur

Harish Ramchandran

Ambarish Purohit

A satellite communication system with software defined network orchestration. Implementations include a route management function (RMF) that receives link status from the satellites and determines simple routing tables which are uploaded to the satellites. The routing tables allow the satellites to route data based on a satellite ID placed in a data header to reduce the memory and computing load on satellite resources. Further, implementations include secure user terminal (UT) to UT IP routing in the constellation for direct UT to UT communication. The satellite communication system may combine the benefits of Medium Earth Orbit (MEO) and Low Earth Orbit (LEO) satellite systems into an MEO-LEO satellite system.

Satellite communication system with software defined network orchestration

A satellite communication system that combines the benefits of Medium Earth Orbit (MEO) and Low Earth Orbit (LEO) satellite systems into an MEO-LEO satellite system. The MEO-LEO system includes an LEO constellation combined with a MEO constellation where the LEO constellation may provide global coverage with broad average capacity and may support 'hot spot' coverage where desired. The MEO constellation may provide unique advantages including backhaul to ground in remote areas, higher traffic density for key locations, and a secure global backhaul for key customers. Data may be routed over optical inter-satellite links using Software Defined Networking concepts to provide MEO-LEO (backhaul and ground access), LEO-LEO (upstream & downstream); and (3) MEO-MEO (crosslinks & downlinks). Further, implementations described herein include secure user terminal (UT) to UT IP routing in the constellation for direct UT to UT communication.

Integrated MEO-LEO satellite communication system

Techniques described herein provide phase and amplitude calibration of phased array antennas. In an N-by-M phased array having N*M channels, embodiments use aggregated measurements over multiple concurrently active channels to improve signal-to-leakage performance, while also using sequences of exclusion groups to yield an individualized calibration value for each channel (i.e., N*M individualized calibration values). For example, a J&#xd7;K channel group of the array is selected in each of a sequence of measurement frames based on a calibration schema. Over J*K measurement sub-frames, a set of J*K aggregate measurements is obtained, each with different subsets of the channel group activated and excluded from the measurement. The aggregate calibration measurements can be used to compute J*K individualized calibration values, each for a channel of the channel group. In some implementations, each calibration value is computed as a complex value including both amplitude and phase calibrations information.

Amplitude and phase calibration for phased array antennas

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.

System and method for networked scheduling for improved spectral efficiency

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 L&#xd7;M 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={k1, k2, . . . , kL} pertubations 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.

Placement of calibration earth stations for ground based beam forming in a satellite system

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.

Approaches for high speed global packet data services for LEO/MEO satellite systems

A method for iterative estimation of a set of unknown channel parameters in a beamforming network including determining a first order estimate of offsets at measurement nodes and an estimate of the confidence in the initial estimate of the measurement nodes' offsets, and iterating, until a desired estimation accuracy is obtained, determining an improved estimate of a parameter set, and the confidence in the estimates, using the prior estimate of the offsets at the measurement nodes and determining an improved estimate of the offsets at the measurement nodes and the associated confidence values using the prior estimate of the parameter set and the corresponding confidence values.

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Boyds, MD, United States of America

Xiaoling Huang