Spacecraft with active antenna array protected against temperature extremes

• US 5,927,654 A
• Filed: 05/16/1997
• Issued: 07/27/1999
• Est. Priority Date: 05/16/1997
• Status: Expired due to Term

• Current Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Original Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Inventors: Foley, James Paul, Murray, Bronson
• Primary Examiner(s): Barefoot, Galen L.
• Application Number:
  US08/856,420
• Time in Patent Office: 802 Days
• Field of Search: 244/173, 244/168, 136/292, 136/245, 343/878, 343/70 S, 343/DIG. 2
• US Class Current: 244/172.6
• CPC Class Codes: B64G 1/1007 Communications satellites
• CPC Class Codes: B64G 1/222 for deploying structures between a stowed and deployed state
• CPC Class Codes: B64G 1/2222 Folding
• CPC Class Codes: B64G 1/443 Photovoltaic cell arrays
• CPC Class Codes: B64G 1/50 for temperature control
• CPC Class Codes: B64G 1/503 Radiator panels
• CPC Class Codes: B64G 1/58 Thermal protection, e.g. heat shields
• CPC Class Codes: B64G 1/66 Arrangements or adaptations of apparatus or instruments, not otherwise provided for
• CPC Class Codes: H01Q 1/28 Adaptation for use in or on aircraft, missiles, satellites, or balloons
• CPC Class Codes: H01Q 3/26 varying the relative phase or relative amplitude of energisation between two or more active radiating elements; varying the distribution of energy across a radiating aperture H01Q3/12, H01Q3/22, H01Q3/24 take precedence

Abstract

A spacecraft carries a deployable active antenna array panel(s) and a deployable solar array panel(s). In the stowed condition, the antenna array panel(s) is sandwiched between a side of the body of the spacecraft and the solar array panel(s). This stowed state prevents the antenna panels from becoming too cold by radiation, or too hot by insolation, in an intermediate orbit. The outermost solar panel preferably has its active surface facing outward, so that it can generate electricity in the intermediate orbit.

Claims

1. A spacecraft, comprising:

a body;

a deployable active antenna array including at least one active antenna array panel defining an electromagnetic energy radiating first side and a heat radiating second side, said active antenna array panel, in a stowed state, being stowed with one of said first and second sides facing said body and the other one of said first and second sides more remote from, and facing away from said body, in such a manner that said body tends to prevent radiation to and from one of said first and second sides of said antenna panel, and in a deployed state, said active array panel being ultimately supported by said body in a location in which said electromagnetic energy radiating first side and said heat radiating second side of said antenna panel radiate substantially free from impediment of radiation by said body; and

a deployable solar array including at least one solar panel defining an active side responsive to solar radiation for producing electrical energy, said solar array panel, in a deployed state, being located relative to said antenna array panel in such a manner as not to substantially impede said radiation of heat and electromagnetic energy therefrom, and in a stowed state, being stowed in proximity to that one of said first and second sides of said antenna array panel remote from said body, whereby said solar array panel tends to insulate said antenna array panel against temperature changes attributable to radiative gain or loss of heat.

2. A spacecraft according to claim 1, wherein said solar panel is stowed with said active side of said solar panel remote from said antenna array panel and exposed to space, whereby, before deployment, said solar panel can, when exposed to solar radiation, produce electrical energy.

3. A spacecraft according to claim 1, wherein, in said deployed state, said antenna array panel is physically interposed between said body of said spacecraft and said solar array panel, so that said solar array panel is not supported directly by said body of said spacecraft, but is instead supported by way of said antenna array panel.

4. A spacecraft according to claim 3, wherein said solar array panel is physically coupled to said antenna array panel by a rotatable joint, whereby said solar array panel can be rotated relative to said antenna array panel.

5. A spacecraft according to claim 1, further comprising:

a thruster coupled to said body; and

at least one propellant tank mounted on said body, and coupled to said thruster for controllably providing propellant thereto.

6. A spacecraft, comprising:

a body;

an active antenna array comprising a plurality of active antenna array panels, each defining an electromagnetic signal radiating first broad side and a second broad side, said active antenna array panels, in a stowed state, being stacked together to form a stack with one of said first and second broad sides facing said body and with another of said broad sides facing away from said body, said stack of active antenna array panels being held against said body in said stowed state, said active antenna array panels, in a deployed state, each having said first broad side facing the Earth and said second broad side facing into space; and

a solar array including a solar panel stack comprising at least one solar panel, each solar panel of said solar panel stack defining an active side responsive to solar radiation for producing electrical energy for energizing at least said antenna array, said solar array, in a deployed state, being located relative to said antenna array panels in such a manner as not to substantially impede radiation therefrom, and, in a stowed state, having a broad side of said solar panel stack adjacent to that broad side of said stack of antenna array panels which is most remote from said body, whereby, before deployment, said solar panel stack tends to insulate said antenna array panels against temperature changes attributable to radiative gain or loss of heat.

7. A spacecraft according to claim 6, wherein said solar array is stowed with said active side of the outermost solar panel of said solar panel stack remote from said antenna array panel and exposed to space, whereby said solar panel can produce electrical energy when exposed to solar radiation in the stowed state.

8. A spacecraft according to claim 7, wherein said solar array includes a plurality of solar array panels, and said outermost solar array panel, in said stowed state, is spaced away from said stack of antenna panels by at least one additional solar array panel.

9. A method for launching a spacecraft into an orbit, comprising the steps of:

providing a spacecraft including a body, at least one active array antenna panel, and a solar panel;

stowing said active array antenna panel against said body;

stowing said solar panel over said active array antenna panel, to thereby form a launchable spacecraft in which said active antenna array panel is sandwiched between, and thermally protected by, said body and said solar panel;

mounting said launchable spacecraft on a booster;

launching said launchable spacecraft into an intermediate orbit;

from said intermediate orbit, performing a velocity change maneuver to achieve another orbit;

in said other orbit, deploying said solar panel; and

in said other orbit, deploying said active array antenna panel.

10. A method according to claim 9, wherein:

said step of stowing said solar panel includes the step of stowing said solar panel with an active side of said solar panel facing away from said active array antenna panel; and

further comprising the steps of

in said intermediate orbit, orienting said active side of said solar panel for receiving solar radiation to thereby generate electrical energy in said solar panel; and

in said intermediate orbit, using said electrical energy to operate at least portions of said spacecraft.

11. A spacecraft, comprising:

a body;

a deployable active antenna array including at least one active antenna array panel defining an electromagnetic energy radiating first side and a heat radiating second side, said active antenna array panel, in a stowed state, being stowed with one of said first and second sides facing said body and the other one of said first and second sides more remote from, and facing away from said body, in such a manner that said body tends to prevent radiation to and from one of said first and second sides of said antenna panel, and in a deployed state, said active array panel being ultimately supported by said body in a location in which said electromagnetic energy radiating first side and said heat radiating second side of said antenna panel radiate substantially free from impediment of radiation by said body; and

a deployable solar array including at least one solar panel defining an active side responsive to solar radiation for producing electrical energy, said solar array panel, in a deployed state, being located relative to said antenna array panel in such a manner as not to substantially impede said radiation of heat and electromagnetic energy therefrom, and in a stowed state, being stowed in proximity to that one of said first and second sides of said antenna array panel remote from said body, whereby said solar array panel tends to insulate said antenna array panel against temperature changes attributable to radiative gain or loss of heat.