Precise satellite ranging and timing system using pseudo-noise bandwidth synthesis

• US 5,041,833 A
• Filed: 06/04/1990
• Issued: 08/20/1991
• Est. Priority Date: 03/28/1988
• Status: Expired due to Fees

• Current Assignee: ITT Manufacturing Enterprises, Inc. (ITT, Inc.)
• Original Assignee: Stanford Telecommunications, Inc. (Nokia Corporation)
• Inventors: Weinberg, Aaron
• Primary Examiner(s): Blum, Theodore M.
• Application Number:
  US07/534,328
• Time in Patent Office: 442 Days
• Field of Search: 342/352, 342/356, 342/357, 342/457, 342/458, 364/459
• US Class Current: 342/357.48
• CPC Class Codes: G01S 11/08 using synchronised clocks
• CPC Class Codes: G01S 5/14 Determining absolute distances from a plurality of spaced points of known location
• CPC Class Codes: H04B 7/18552 using a telephonic control signal and a second ranging satellite determining absolute distances from a plurality of spaced points of known location G01S5/14

Abstract

A precise ranging and timing system using pseudo-noise bandwidth synthesis to provide precise orbit determination for geosynchronous and low earth orbit satellites, navigation of low earth orbiting satellite through signals transmitted through geosynchronous satellites and precise time-transfer. The system includes a novel signal structure which is comprised of disjoint, narrow band, spectral components spread over a wide bandwidth. The number of spectral components, their individual bandwidths, and their specific spectral locations over the end-to-end spread bandwidth determine the ultimate capabilities and performance achievable. The broad beam transmission of the precise ranging and timing system signal via a geosynchronous satellite provide the precise ranging and timing system capability to suitably equipped users for a multiplicity of purposes including: (1) precise orbit determination, (2) navigation of low-earth orbiting satellites through signals transmitted through geosynchronous satellites, and (3) precise time transfer.

Claims

1. A satellite ranging and timing system in which a master station on earth transmits signals to an earth orbiting communication satellite and a plurality of remote stations within radio view of said satellite and communicate with each other and said master station via said communications satellite, said ranging and timing system including,

means at said master station for generating and transmitting a wide bandwidth pseudo-noise signal, said wide bandwidth pseudo-noise signal being comprised of a plurality of disjoint narrow-band spectral components,

said master station including a master system clock for controlling the generation and transmission of said wide bandwidth pseudo-noise signal, and means for determining from return of components of said pseudo-noise signal from said earth orbiting communication satellite orbit data of said satellite and transmitting said orbit data to all other stations via said satellite,

means at each of said plurality of remote stations for receiving said wide-band pseudo-noise signal and deriving data including range information to said communications satellite,

means at each of said stations for transmitting said range information to said master station, and

means at said master station for receiving said wide-band pseudo-noise signal and deriving data including range information for said stations from different ones of said disjoint narrow-band spectral components and determining orbit data of said communication satellite and provide real time satellite position data.

2. A satellite ranging and timing system in which a master station on earth transmits signals to an earth orbiting communication satellite and a plurality of remote stations within radio view of said satellite communicate with each other and said master station via said communications satellite, said ranging and timing system including,

means at said master station for generating and transmitting a wide bandwidth pseudo-noise signal, said wide bandwidth pseudo-noise signal being comprised of a plurality of disjoint narrow-band spectral components, and

means at each of said plurality of remote stations for receiving said wide-band pseudo-noise signal and deriving data including range information to said communications satellite,

means at each of said stations for transmitting said range information to said master station,

means at said master station for receiving said range information from said remote stations, said master station including means providing a calibration signal, and

means at said master station for determining the orbit data of said satellite from said range information and said calibration information and producing real time satellite position data at each of said stations.

3. The satellite ranging and timing system defined in claim 2 wherein,

said master station includes a master system clock for controlling the generation and transmission of said wide bandwidth pseudo-noise signal, and means for determining from return of components of said pseudo-noise signal from said earth orbiting communications satellite orbit data of said satellite and transmitting said orbit data to all other stations via said satellite.

4. A satellite ranging and timing system in which a master station on earth transmits pseudo-noise signals to an earth orbiting communications satellite and a plurality of remote station within radio view of said satellite to communicate with each other and said master station via said communication satellite, said ranging and timing system including:

means at said master station for generating and transmitting a wide-band pseudo-noise signal, said wide-band pseudo-noise signal being comprised of a plurality of mutually coherent disjoint, narrow-band, spectral components which are frequency division multiplexed over said wide-band width, and

means at said master station for receiving said wide-band pseudo-noise signal, demultiplexing same and deriving data including range information for said stations from different ones of said disjoint narrow-band spectral components.

5. A satellite ranging and timing system defined in claim 4 wherein at least one of said plurality of remote stations includes means for receiving and demultiplexing said wide-band pseudo-noise signal and deriving data including range information for that station from said disjoint narrow-band spectral components of said frequency division multiplexed wide-band signal.