Aerospace & Defense Technology - June 2024 - 29

RF & Microwave Technology
reduced, as expected. During the April
8 test, the spacecraft transmitted test
data at a maximum rate of 25 Mbps,
which far surpasses the project's goal
of proving at least 1 Mbps was possible
at that distance.
The project team also commanded
the transceiver to transmit Psyche-generated
data optically. While Psyche was
transmitting data over its radio frequency
channel to NASA's Deep Space Network
(DSN), the optical communications
system simultaneously transmitted
a portion of the same data to the Hale
Telescope at Caltech's Palomar Observatory
in San Diego County, California -
the tech demo's primary downlink
ground station.
" After receiving the data from the DSN
and Palomar, we verified the optically
downlinked data at JPL, " said Ken
Andrews, project flight operations lead
at JPL. " It was a small amount of data
downlinked over a short time frame, but
the fact we're doing this now has surpassed
all of our expectations. "
Fun With Lasers
After Psyche launched, the optical
communications demo was initially used
to downlink pre-loaded data, including
the Taters the cat video. Since then, the
project has proven that the transceiver
can receive data from the high-power
uplink laser at JPL's Table Mountain facility,
near Wrightwood, California. Data
can even be sent to the transceiver and
then downlinked back to Earth on the
same night, as the project proved in a
recent " turnaround experiment. "
This experiment relayed test data - as
well as digital pet photographs - to Psyche
and back again, a round trip of up to
280 million miles (450 million kilometers).
It also downlinked large amounts
of the tech demo's own engineering data
to study the characteristics of the optical
communications link.
" We've learned a great deal about how
far we can push the system when we do
have clear skies, although storms have
interrupted operations at both Table
Mountain and Palomar on occasion, "
said Ryan Rogalin, the project's receiver
electronics lead at JPL. (Whereas radio
frequency communications can operate
in most weather conditions, optical
Aerospace & Defense Technology, June 2024
communications require relatively clear
skies to transmit high-bandwidth data.)
JPL recently led an experiment to
combine Palomar, the experimental
radio frequency-optical antenna at the
DSN's Goldstone Deep Space Communications
Complex in Barstow, California,
and a detector at Table Mountain to
receive the same signal in concert.
" Arraying " multiple ground stations to
mimic one large receiver can help boost
the deep space signal. This strategy can
also be useful if one ground station is
forced offline due to weather conditions;
other stations can still receive the signal.
More About the Technology
Demonstration
Managed by JPL, this demonstration is
the latest in a series of optical communication
experiments funded by the Technology
Demonstration Missions (TDM)
program under NASA's Space Technology
Mission Directorate and the agency's
Space Communications and Navigation
(SCaN) program within the Space Operations
Mission Directorate. Development
of the flight laser transceiver is supported
by MIT Lincoln Laboratory, L3 Harris,
CACI, First Mode, and Controlled
Dynamics Inc., and Fibertek, Coherent,
and Dotfast support the ground systems.
Some of the technology was developed
through NASA's Small Business Innovation
Research program.
Arizona State University leads the Psyche
mission. JPL is responsible for the
mission's overall management, system
engineering, integration and test, and
mission operations. Psyche is the 14th
mission selected as part of NASA's Discovery
Program under the Science Mission
Directorate, managed by the agency's
Marshall Space Flight Center in
Huntsville, Alabama. NASA's Launch
Services Program, based at the agency's
Kennedy Space Center in Florida, managed
the launch service. Maxar Technologies
provided the high-power solar
electric propulsion spacecraft chassis
from Palo Alto, California.
This article was written by Ian J.
O'Neill, Media Relations Specialist and
Writer, Jet Propulsion Laboratory, NASA
(Pasadena, CA). For more information,
visit jpl.nasa.gov.
mobilityengineeringtech.com
29
http://info.hotims.com/86256-748 http://jpl.nasa.gov http://mobilityengineeringtech.com
Aerospace & Defense Technology - June 2024

Table of Contents for the Digital Edition of Aerospace & Defense Technology - June 2024
