Back to results
US 4,727,373 AGranted
Method and system for orbiting stereo imaging radar
AssigneeLoral Corporation
InventorMilton B. Hoover
Life of this patent
Estimating the term…
Abstract
This radar system makes it possible to collect complete stereo data in a single pass by utilizing an orbiting, side looking, bi-static, synthetic aperture radar. This system utilizes at least two orbiting spacecraft in synchronous parallel orbits with each other and separated by a tether. A transmitter transmits radar signals to a planet's surface which are reflected back and received by two receivers, one carried by each spacecraft. When the signals are combined, the layover produces a three dimensional picture in which vertical height information may be determined.
Claims35
An orbiting, stereo, side looking, synthetic aperture radar system for imaging a surface area of a planet comprising:
- a plurality of spacecrafts, spatially separated by a predetermined distance, in synchronous parallel orbits with each other, and passing along a flight path to one side of said area;
- a transmitting means carried by one spacecraft for transmitting a pulse of coherent radar signals to illuminate and reflect off of said surface, and oriented such that said signals are transmitted perpendicular to said flight path and along a predetermined vertical angle relative to said imaged surface;
- two receiving means, each carried by a different spacecraft, for each receiving a set of data corresponding to said reflected signals, including amplitude and phase information, collected from different vertical angles relative to the imaged surface;
- and
- wherein said transmitting means is interlocked with said receiving means such that subsequent pulse signals are isolated from the previous reflected signals.
2 more elements
A method of providing stereo imaging of a surface area of a planet comprising the steps of:
- (a) deploying a first spacecraft in orbit about such planet, said spacecraft carrying at least one other spacecraft and said orbit having a flight path to one side of said area to be imaged;
- (b) deploying such carried spacecraft into a gravity stabilized orbiting assembly wherein said spacecrafts are in substantial linear alignment and spatially separated by a predetermined distance with one another, having at least one spacecraft located substantially below and closer to the planet than the other and wherein said separation is maintained by a tether operatively connected between said spacecraft;
- (c) passing said assembly along said flight path;
- (d) transmitting from one spacecraft a pulse of coherent radar signals perpendicularly to said flight path and along a predetermined vertical angle relative to said imaged surface, to illuminate and reflect off of said surface;
- (e) one spacecraft receiving a first set of data corresponding to said reflected signals received along a first predetermined receiving angle, including amplitude and phase information;
- and
- (f) another spacecraft receiving a second set of data including amplitude and phase information, corresponding to said reflected signals received along a second predetermined receiving angle.
4 more elements
A method of providing stereo imaging of a surface area of a planet comprising the steps of:
- (a) deploying a plurality of spacecraft into a gravity stabilized orbiting assembly wherein said spacecrafts are in substantial linear alignment and spatially separated by a predetermined distance with one another, having at least one spacecraft located substantially below and closer to the planet than the other and said orbit having a flight path to one side of said area to be imaged;
- (b) passing said assembly along said flight path;
- (c) transmitting from one spacecraft a pulse of coherent radar signals perpendicularly to said flight path and along a predetermined vertical angle relative to illuminate and reflect off of said surface area;
- (d) one spacecraft receiving a first set of data corresponding to said reflected signals received along a first predetermined receiving angle, including amplitude and phase information;
- and
- (e) another spacecraft receiving a second set of data including amplitude and phase information, corresponding to said reflected signals received along a second predetermined receiving angle.
3 more elements
A gravity stabilized apparatus for providing stereo imaging of a surface area of a planet comprising:
- a plurality of housings capable of orbiting the surface of a planet;
- a tether operatively connected between such housings adapted to provide a predetermined spacing between such housings;
- a transmitting means carried by one housing for transmitting a pulse of coherent radar signals to illuminate and reflect off of such surface;
- two receiving means, each carried by a different housing for receiving a set of data corresponding to said reflected signals received along different receiving angles;
- and
- wherein said transmitting means is interlocked with said receiving means such that subsequent pulse signals are isolated from the previous reflected signals.
3 more elements
A gravity stabilized apparatus for providing stereo imaging of a surface area of a planet comprising:
- a first housing, having at least one opening therein and carrying at least one other housing, said housings capable of orbiting a planet's surface;
- a tether operatively connected between such housings adapted to provide a predetermined spacing there between;
- a transmitting means carried by one housing for transmitting a pulse of coherent radar signals to illuminate and reflect off of such surface;
- two receiving means, each carried by a different housing for receiving a set of data corresponding to said reflected signals received along different receiving angles;
- wherein said transmitting means is interlocked with said receiving means such that subsequent pulse signals are isolated from the previous reflected signals;
- at least one separation means carried by said first housing for providing an initial thrust to such other housings, causing them to pass through said openings;
- and
- at least one deployment means carried by at least said first housing for running out or retracting said tether, and providing said separation between said housings.
5 more elements
Dependencies are inferred from the claim text.