The Johns Hopkins University

USA As Represented by Secretary of the Navy

William S Devereux

Dennis J Duven

Mark S Asher

Lloyd A Linstrom

Thomas L Kusterer

Edwin E Westerfield

Richard C Morgan

Albert A Chacos

Kim Strohbehn

Robert C Moore

Thomas R McKnight, Jr

Patrick A Stadter

Michael H Boehme

John R Meyer

Robert J Heins

Don M Gruenbacher

Larry L Warnke

Paul D Grimm

Paul R Snow

An autonomous navigation system for an orbital platform incorporating a global positioning system based navigation device optimized for low-Earth orbit and medium-Earth orbit applications including a 12 channel, GPS tracking application-specific integrated circuit () operating in concert with a computer system () implementing an extended Kalman filter and orbit propagator which autonomously generates estimates of position, velocity and time to enable planning, prediction and execution of event-based commanding of mission operations.

Extended kalman filter for autonomous satellite navigation system

An integrated navigation and communication system that enables distributed spacecraft system operations. The system is a modular, extensible system that supports science operations among multiple, distributed spacecraft by implementing the essential functions of navigation, communication and control. Distributed spacecraft systems, also called formation flying systems, extend the capabilities of single-spacecraft missions by providing a platform for complex sensing tasks, including multipoint observation, co-observation, and distributed apertures. To accomplish these tasks, the system enables spacecrafts within a distributed spacecraft system to communicate science and coordination information, to determine relative position, velocity and time for command and control operations, and to operate in a coordinated manner to achieve common mission goals.

Integrated navigation and communication system for use in distributed spacecraft systems

An autonomous navigation system for an orbital platform incorporating a global positioning system based navigation device optimized for low-Earth orbit and medium-Earth orbit applications including a 12-channel, GPS tracking application-specific integrated circuit operating in concert with a microprocessor implementing an extended Kalman filter and orbit propagator which autonomously generates estimates of position, velocity, and time to enable planing, prediction and execution of event-based commanding of mission operations.

Autonomous satellite navigation system

A small, multi-function device called the GPS/Telemetry Transmitter (GTT) that can recover telemetry (TM) data from missiles, spacecraft, balloons, or any moving platform or vehicle, and generate high accuracy trajectory estimates using GPS data is disclosed. Additionally, the concept underlying the GTT of transmitting high-data-rate telemetry and instrument data concurrently with transdigitized GPS data is incorporated in a GPS-Linked Transponder (GLT) resulting in a simpler and cheaper satellite positioning system.

Global positioning system (GPS) linked satellite and missile

A variable pulse rate circuit for correlating a locally generated code with code that is being transmitted by a space vehicle. A computer means is used for providing a binary word to a latch. The binary word in the latch is used in turn by a delay line, to control the amount of delay that is presented to pulses. The pulses are emitted by a pulse generator having a fixed rate reference. The pulse rate, of pulses being emitted by of the delay line, is varied from the reference pulse rate. This variation is the result of computer means that rapidly changes the amount of delay of the delay line. The pulse rate and the pulse phase are varied in order to cause a locally generated code to become phase aligned with the code received from the space vehicle. The space vehicle is tracked using the variable pulse rate circuit.

Variable pulse rate circuit

An apparatus for generating pseudo-random codes is disclosed. The apparatus uniquely stores a set of codes in a memory and uniquely retrieves a particular code sequence. The apparatus has particular application to Global Position Satellite (GPS) earth receivers.

Pseudo-Random code generator for use with a global positioning system

Growing community of inventors

Glenwood, MD, United States of America

William S Devereux