Satellite Communications

Artist rendering of NASA’s Galileo spacecraft communicating with Earth after entering Jupiter’s orbit.[5]

Communication capability in space is critical.  From far-flung spacecraft orbiting in the outer reaches of our solar system to those in Earth’s orbit, the ability to send and receive information accurately and efficiently to and from these satellites is important.  In the 1970s, NASA began developing an advanced communication system using compressed data and concatenated coding channels to provide error free communication at improved data transmission rates.  This technology was successfully implemented in both the Voyager 1 and 2 spacecraft and in the Galileo spacecraft on its mission to orbit Jupiter, and is now incorporated in the technical standards used in most spacecraft communication systems.[6]

Aspects of this communication technology are described in U.S. Patent No. 3,988,677 entitled “Space Communication System for Compressed Data with a Concatenated Reed-Solmon-Viterbi Coding Channel.”[7] In accordance with NASA’s information sharing mandate, this NASA patent, granted Oct. 26, 1976, states a primary object of describing a new communication system for communicating data from a spacecraft to Earth and was reported in the NASA PAB.[8]

The technology has progressed in the decades since, including development for many satellite applications in Earth’s orbit.  For example, NASA’s Tracking and Data Relay Satellite (TDRS) system consists of a number of satellites in geosynchronous orbit that provide command, telemetry and science data between satellites and the ground, acting as information relays for many NASA missions.  NASA continues to implement and share new modulation and coding innovations for this relay system.[9]  Beyond NASA satellites, concatenated convolutional and Reed-Solomon channel coding technology is used globally by most commercial satellite operators for television and data broadcasting services, and the technology continues to see progressive advancements.[10]

Digital Imaging

Pictures from space are often extraordinary.  Whether a strange view of a vibrant galaxy or a landscape from the surface of a distant world, space images can be impactful and even emotionally resonating.  NASA has long recognized the need for space imaging for scientific purposes as well as public interest.  
For camera technology to be suitable for use in space,  it must meet stringent imaging capability and power requirements. Space vehicles of all kinds, including planetary rovers, like Perseverance on the surface of Mars, must be able to capture and process images using onboard cameras and processors, transmit these images back to Earth, and have sufficient power available to do so.[12]

A seminal camera imaging innovation for space applications is described in U.S. Patent No. 5,471,515, granted Nov. 28, 1995, entitled “Active Pixel Sensor with Intra-Pixel Charge Transfer.” This patent details a new design for a silicon imaging device which can be fabricated using a complementary metal oxide semiconductor (CMOS) process. [13]  An advance over the use of known charge-coupled devices (CCD) for imaging, this innovation, developed at the Jet Propulsion Laboratory under a NASA contract, uses a technique for intra-pixel charge transfer that allows for improved imaging using less power than CCD devices and that can be readily integrated into a computer chip. 

The digital imaging capability enabled by this CMOS technology was a major development in producing small, low-power cameras, perfect for incorporation into consumer electronics.  It has become one of the most omnipresent spinoff technologies from NASA that is used in nearly all smartphone cameras today.[14]

Picture of the Perseverance rover on the surface of Mars, taken as a selfie using the WATSON (Wide Angle Topographic Sensor for Operations and eNgineering) camera on the end of the rover’s two-meter-long robotic arm[15]
 
 
Figure from U.S. Patent No. 5,471,515, granted Nov. 28, 1995, entitled “Active Pixel Sensor with Intra-Pixel Charge Transfer”

Digital imaging using a smartphone camera [16]

Thermal Insulation and Space Blankets

The Cassini spacecraft and attached  Huygens probe, both with gold-colored thermal insulation blankets[17]
 

Figure from U.S. Patent No. 3,007,596, granted Nov. 7, 1961, entitled “Thermal Insulation”

“Space Blanket” from the 1980s, identified as “A GENUINE ‘NASA SPIN-OFF’ PRODUCT”[22]

The temperature of a spacecraft can fluctuate dramatically depending on sun exposure.  As a result, spacecraft need to be thermally insulated to mitigate the extreme temperature changes in space and to protect onboard equipment.  For example, NASA’s Cassini spacecraft on its mission to Saturn, with attached Huygens probe from the European Space Agency that landed on Saturn’s moon Titan, experienced temperature ranges from 482 to minus 364 degrees Fahrenheit (250 to minus 220 degrees Celsius). [18]  Anticipating this, NASA protected much of the spacecraft and probe by thin, gold-colored, reflective aluminized thermal insulation blankets.

Investigating thin, reflective insulation materials was a particular focus for NASA and its contractors for manned space programs in the 1960s.  Developed especially for the Apollo program, these insulation materials quickly became technology widely employed for thermal control on many spacecraft.  U.S. Patent No. 3,007,596, granted Nov. 7, 1961, entitled “Thermal Insulation,” developed under a NASA contract, describes techniques for producing thin aluminum foils supported by fiber sheets as reflective, multilayer insulation coverings. [19]  This technology was dubbed “superinsulation.”[20]

By the 1980s, the benefit and practicality of thin superinsulation blankets for commercial applications had gained traction, particularly for emergency preparedness and outdoor enthusiasts.  The “Space Blanket,” as it was commonly termed, became one of the first widely-known NASA spinoff technologies to reach the public consciousness in multiple forms of commercial products, from souvenirs to marathon blankets. [21]

Solar Energy

A spacecraft needs power to operate.  On missions to the inner planets, the sun is a viable option for providing necessary power using solar panels arranged in arrays to generate electricity from sunlight.  Not only spacecraft, but landers, like Mars Pathfinder, and rovers, like Sojourner, Spirit and Opportunity, have all harnessed the sun’s energy on the surface of Mars using solar arrays.  Closer to home, Earth-orbiting space vehicles are also perfectly situated for utilizing solar energy, such as the International Space Station (ISS) that generates power from eight main solar arrays, along with a new type of roll-out solar array recently installed by NASA on the ISS for additional power generation.[23]

NASA has been developing and improving solar panels and their manufacture for decades for space-related purposes.  For example, U.S. Patent No. 3,565,719, granted Feb. 23, 1971, entitled “Solar Panel Fabrication,” describes a method of fabricating solar cells on a substrate in a manner designed to achieve the high reliability required for solar power generation in space. [24]  Upon grant, this patent was reported by NASA in its STAR announcement for information dissemination purposes.[25]

The advances in solar panel technology by NASA and many others over the last decades have produced abundant efforts and initiatives directed to helping meet the electricity requirements of society using solar power generation.  It has been estimated that in 2022 nearly 1300 terawatt hours (TWh) of energy was generated globally by solar power.[26]  Looking forward, NASA continues to boldly innovate for the future use of solar power to help meet energy needs here on Earth.  Recently, NASA has considered tantalizing new concepts for generating space-based solar power, including delivering microwave energy to Earth from solar energy collected in space, driving forward technologies where no one has innovated before. [27]

Existing solar panels on the ISS along with installation of a new roll-out type of solar array[28]

Figure from U.S. Patent No. 3,565,719, granted Feb. 23, 1971, entitled “Solar Panel Fabrication”

Space-based solar power concepts by NASA to deliver microwave energy to Earth from solar energy collected in space[29]