Scalable satellite data communication system that provides incremental global broadband service using earth-fixed cells

• US 6,850,732 B2
• Filed: 03/29/2002
• Issued: 02/01/2005
• Est. Priority Date: 03/30/2001
• Status: Expired due to Fees

• Current Assignee: Wengen Wireless LLC (Intellectual Ventures LLC)
• Original Assignee: Wengen Wireless LLC (Intellectual Ventures LLC)
• Inventors: Patterson, David P., Hinedi, Sami, Quadracci, Len, Ghazvinian, Farzad, Sturza, Mark A.
• Primary Examiner(s): Corsaro, Nick
• Assistant Examiner(s): Trinh, Tan
• Application Number:
  US10/113,840
• Publication Number:
  US 20030050008A1
• Time in Patent Office: 1,040 Days
• Field of Search: 455/12.1, 455/13.2, 455/13.3, 455/561, 455/427, 455/430, 455/525, 455/554.2, 455/575.7
• US Class Current: 455/12.1
• CPC Class Codes: H04B 7/18578 Satellite systems for providing broadband data service to individual earth stations for selecting H04W; provisions for broadband connection, H04Q11/0478

Abstract

A scalable satellite data communication system that provides incremental global broadband services using Earth-fixed cells may begin with a limited satellite deployment that initially serves a limited number of Earth-fixed cells. The system has the flexibility to incrementally increase the number of Earth-fixed cells that are served, with minimal constraints on the relative locations of the cells on the Earth, by adding satellites of potentially greater complexity to the system. Backward compatibility with existing user terminals is achieved by maintaining the same satellite communication interface as with the already-deployed satellite constellation. Continuous and/or non-continuous service may be provided to selected Earth-fixed cells. Scheduled non-continuous service is particularly advantageous for bulk data transport services. Satellites may use simple mechanically-steered antennas. Communication links may be handed from one satellite to another when one satellite moves out of range and is no longer able to cover a selected Earth-fixed cell.

Claims

1. A scalable satellite data communication system for providing incremental global data communication services, comprising:

(a) at least one satellite in non-geosynchronous orbit (NGSO) above the Earth;

(b) at least one user terminal located in a first Earth-fixed cell and having

(i) an antenna capable of tracking the NGSO satellite above a user elevation mask;

(ii) a receiver capable of receiving a forward downlink signal from the NGSO satellite; and

(iii) a transmitter capable of transmitting a reverse uplink signal to the NGSO satellite; and

(c) at least one gateway located in a second Earth-fixed cell and having

(i) an antenna capable of tracking the NGSO satellite above a gateway elevation mask;

(ii) a transmitter capable of transmitting a forward uplink signal to the NGSO satellite;

(iii) a receiver capable of receiving a reverse downlink signal from the NGSO satellite; and

(iv) a connection to a terrestrial data communication network, wherein the gateway receives data from the terrestrial data communication network for forward uplink transmission to the NGSO satellite, and transmits data received from the NGSO satellite via reverse downlink transmission to the terrestrial data communication network;

wherein the NGSO satellite includes

(i) a steerable forward link receive antenna capable of receiving the forward uplink signal from the gateway in the second Earth-fixed cell;

(ii) a steerable forward link transmit antenna capable of transmitting the forward downlink signal to the user terminal in the first Earth-fixed cell;

(iii) a steerable reverse link receive antenna capable of receiving the reverse uplink signal from the user terminal in the first Earth-fixed cell; and

(iv) a steerable reverse link transmit antenna capable of transmitting the reverse downlink signal to the gateway in the second Earth-fixed cell; and

wherein the satellite data communication system provides a communication link between the user terminal and the terrestrial data communication network via the NGSO satellite and the gateway; and

wherein the satellite data communication system is configured for incremental expansion in multiple stages by adding additional NGSO satellites that can be of different design or in different orbital configuration, the additional satellites providing data communication capabilities for additional user terminals and gateways located in additional Earth-fixed cells, the additional satellites being further configured to be backward compatible to communicate with existing user terminals and gateways in the satellite data communication system.