NASA’s new experimental antenna tracks deep space laser

An experimental antenna has obtained each radio frequency and near-infrared laser alerts from NASA’s Psyche spacecraft because it travels by deep space. This reveals it is doable for the large dish antennas of NASA’s Deep Area Community (DSN), which talk with spacecraft by way of radio waves, to be retrofitted for optical or laser communications.

By packing extra knowledge into transmissions, optical communication will allow new space exploration capabilities whereas supporting the DSN as demand on the community grows.

The 34-meter (112-foot) radio-frequency-optical-hybrid antenna, referred to as Deep Area Station 13, has tracked the downlink laser from NASA’s Deep Area Optical Communications (DSOC) know-how demonstration since November 2023. The tech demo’s flight laser transceiver is using with the company’s Psyche spacecraft, which launched on Oct. 13, 2023.

The hybrid antenna is positioned on the DSN’s Goldstone Deep Area Communications Complicated, close to Barstow, California, and is not a part of the DSOC experiment. The DSN, DSOC, and Psyche are managed by NASA’s Jet Propulsion Laboratory in Southern California.

“Our hybrid antenna has been capable of efficiently and reliably lock onto and monitor the DSOC downlink since shortly after the tech demo launched,” mentioned Amy Smith, DSN deputy supervisor at JPL. “It additionally obtained Psyche’s radio frequency sign, so we now have demonstrated synchronous radio and optical frequency deep space communications for the primary time.”

In late 2023, the hybrid antenna downlinked knowledge from 20 million miles (32 million kilometers) away at a fee of 15.63 megabits per second—about 40 instances sooner than radio frequency communications at that distance. On Jan. 1, 2024, the antenna downlinked a staff {photograph} that had been uploaded to DSOC earlier than Psyche’s launch.

Two for one

So as to detect the laser’s photons (quantum particles of sunshine), seven ultra-precise segmented mirrors have been hooked up to the within of the hybrid antenna’s curved floor. Resembling the hexagonal mirrors of NASA’s James Webb Area Telescope, these segments mimic the light-collecting aperture of a 3.3-foot (1-meter) aperture telescope. Because the laser photons arrive on the antenna, every mirror displays the photons and exactly redirects them right into a high-exposure digicam hooked up to the antenna’s sub-reflector suspended above the middle of the dish.

The laser sign collected by the digicam is then transmitted by an optical fiber that feeds right into a cryogenically cooled semiconducting nanowire single photon detector. Designed and constructed by JPL’s Microdevices Laboratory, the detector is equivalent to the one used at Caltech’s Palomar Observatory in San Diego County, California, which acts as DSOC’s downlink floor station.

“It is a high-tolerance optical system constructed on a 34-meter versatile construction,” mentioned Barzia Tehrani, communications floor methods deputy supervisor and supply supervisor for the hybrid antenna at JPL. “We use a system of mirrors, exact sensors, and cameras to actively align and direct laser from deep space right into a fiber reaching the detector.”

Tehrani hopes the antenna can be delicate sufficient to detect the laser sign despatched from Mars at its farthest level from Earth (2 ½ instances the space from the sun to Earth). Psyche can be at that distance in June on its technique to the main asteroid belt between Mars and Jupiter to research the metal-rich asteroid Psyche.

The seven-segment reflector on the antenna is a proof of idea for a scaled-up and extra highly effective model with 64 segments—the equal of a 26-foot (8-meter) aperture telescope—that could possibly be used sooner or later.

An infrastructure answer

DSOC is paving the way in which for higher-data-rate communications able to transmitting complicated scientific data, video, and high-definition imagery in assist of humanity’s subsequent large leap: sending people to Mars. The tech demo just lately streamed the primary ultra-high-definition video from deep space at record-setting bitrates.

Retrofitting radio frequency antennas with optical terminals and developing purpose-built hybrid antennas could possibly be an answer to the present lack of a devoted optical floor infrastructure. The DSN has 14 dishes distributed throughout amenities in California, Madrid, and Canberra, Australia. Hybrid antennas may depend on optical communications to obtain excessive volumes of information and use radio frequencies for much less bandwidth-intensive knowledge, comparable to telemetry (well being and positional data).

“For many years, we now have been including new radio frequencies to the DSN’s large antennas positioned across the globe, so probably the most possible subsequent step is to incorporate optical frequencies,” mentioned Tehrani. “We are able to have one asset doing two issues on the identical time; changing our communication roads into highways and saving time, cash, and sources.”