Ems Technologies, Inc.

Electromagnetic Sciences, Inc.

Steven H Rigg

Thomas Steven Taylor

James M Howell

Thomas E Sharon

William R Hafner

Norman E Johnson

Jeffrey A Leddy

A satellite communications system having ground user terminals, hubs, and a geosynchronous satellite. The satellite generates a network of spot beam coverage areas on the earth. A hub and at least one ground terminal are located in each of at least two spot beams. A first user terminal transmits an uplink signal according to a first signal protocol to the hub through the satellite. A second user terminal receives a downlink signal according to a second signal protocol through the downlink spot beam from the hub through the satellite. The hub may be located in the same spot beam coverage area as the first or the second user terminal or may be located in an altogether different spot beam coverage area. Through selective frequency and/or polarization routing on board the satellite, a hub located within a &ldquo;parent&rdquo; beam can communicate with user terminals within the parent beam at a specified frequency and polarization, and can communicate with users in other &ldquo;dependent&rdquo; beams on a different frequency and/or polarization. This routing allocates the total available bandwidth between parent and dependent beams. The system enables asynchronous communications between each hub and the satellite to maximize frequency re-use and the overall capacity of the system.

Multi-beam satellite communications system

A distributed parallel processing architecture for electronically steerable multi-element RF array antennas provides real time rapid array updates with decreased hardware cost and complexity. The array is subdivided into plural sub-arrays (each sub-array has more than one RF radiating element) and a phase shift interface electronics ('PIE') device is provided for each sub-array. Parameters specific to the RF elements within the sub-arrays are preloaded into the corresponding PIE. Pointing angle and rotational orientation parameters are broadcasted to the PIEs, which then calculate, in parallel and in a distributed processing manner, the phase shifts associated with the various elements in their corresponding sub-arrays. Linearization, phase compensation for various factors (e.g., operating frequency, measured characteristics of individual RF elements, feed line delay to individual elements, etc.), and the initial phase shift calculations themselves are thus performed on essentially an element-by-element basis without requiring individual calculation hardware for each element. Array spoiling in response to real time array rotational orientation is provided. Update rates of greater than 10 kHz are attainable.

Distributed planar array beam steering control with aircraft roll

Growing community of inventors

Norcross, GA, United States of America

Steven H Rigg