The National Aeronautics and Space Administration (NASA) Deep Space Optical Communications (DSOC) Project implemented by the Jet Propulsion Laboratory (JPL), has completed its prime mission from Nov. 14, 2023 - Sep. 2, 2025. The DSOC flight laser transceiver (FLT), hosted by NASA's Psyche spacecraft, along with optical ground stations located in Southern California, were used to meet and exceed sponsor and project requirements. The distances covered over the course of the mission range from 0.37 - 3.3 AU notionally covering the nearest and farthest ranges of Mars. Key updates for the period starting in December of 2024 include operations at the full 4W average laser power instead of the previous half power (2W) operations. A mature pointing controller implemented towards the end of July 2024 was tested for the rest of the mission confirming sustained improved pointing stability. More frequent use of DSOC FLT high-rate telemetry was returned, with the ability to use the optical downlink. This was significant because the Psyche telecommunications backchannel used for returning lower rate telemetry did not have the capacity to downlink the high rate sampled data. A new photon counting receiver signal processing backend indicating better performance than the baseline real-time receiver was demonstrated. The link difficulty, defined as the product of data-rate and range-squared (Mb/s-AU2), using the new receiver achieved a value of 170, which in our estimate is the highest ever achieved. Link demonstrations with external space agencies were completed successfully. In this paper the above topics in addition to a series of link experiments performed will be reported.

The purpose of the Deep Space Optical Communication (DSOC) project is to demonstrate that free space optical communication technology is mature and capable of supporting future deep space missions. Free space optical communications can provide 10-100x higher data rates as compared to RF technology at Mars distances. In addition, the DSOC team characterized the link budget at Mars ranges (0.3-2.6 AU) demonstrating up to 267 Mbps downlink data rates. DSOC operations began two weeks after the flight terminal hosted by the Psyche spacecraft launched October 2023. Weekly contacts between the two optical ground stations and the flight terminal aboard Psyche are on-going until the DSOC prime mission ends September 2025. This paper provides an overview of the DSOC architecture, the two ground station terminals design, operations, and focusing on ground transmitter tests.

The Deep Space Optical Communications (DSOC) project, hosted on the Psyche spacecraft, has recently successfully completed its first year of operations. The flight system involved a laser transmitter assembly (LTA) capable of up to 4 W of average power at 1550 nm with data modulated at up to 267 Mbps using pulse position modulation (PPM) and leveraging telecom components in the design. The downlink laser transmitter operated for over 120 hrs on a weekly cadence at distances up to over 3 AU where 8 Mbps was demonstrated during nighttime operations. The uplink laser assembly (ULA) was integrated into the DSOC ground laser transmitter (GLT) facility at the JPL Optical Communication Telescope Lab and provided a beacon reference for the flight terminal with over 2 kW average power and an uplink data rate of 1.8 kbps at 1064 nm over the entire range. The ULA incorporated up to ten individual laser units based on commercial systems but modified to provide the uplink data modulation. Trends and performance data will be reported on for both systems along with an anomaly in the ground testing of the EM LTA.

NASA's Deep Space Optical Communications (DSOC) Project, implemented by the Jet Propulsion Laboratory (JPL), has successfully completed the first year of its technology demonstration, delivering high-rate optical downlinks for the first time from deep space over spacecraft distances ranging from 0.1 to 3 astronomical units (AU). The heart of the flight terminal is an essentially free-floating 22 cm telescope and photon-counting camera, mounted on a platform that is steered by Lorentz-force actuators. The hardware also includes a 4 Watt transmit laser and associated electronics. The instrument software and firmware algorithms detect and track a modulated optical uplink beacon, decode data modulated on that beacon signal, point the downlink laser, and encode pulse position modulated (PPM) data for the optical downlink. These hardware elements are described, along with the firmware and software signal processing algorithms. The concept of operations for the flight terminal is also described.

The Deep Space Optical Communication (DSOC) project is conducting an ongoing technology demonstration of free-space optical communications over an approximate range of 0.125 to 3.3 AU concurrently with NASA's Psyche mission, which launched on October 13, 2023 and hosts the DSOC flight transceiver (FLT). The DSOC Ground Laser Transmitter (GLT), located at the Jet Propulsion Laboratory's Optical Communication Telescope Laboratory (OCTL), provides a high-power (up to 5 kW on-sky) optical uplink beacon that serves as a line-of-sight FLT downlink pointing reference and delivers low rate (1.8 kbps) uplink command data to the FLT. This paper presents an overview of the GLT subsystems, concept of operations, and results from the first phase of DSOC operations including analysis of the beacon pointing and the performance of the laser safety subsystem.

The Deep Space Optical Communications technology demonstration is a hosted payload on the Psyche Mission spacecraft that launched October 2023. Weekly contacts are characterizing the link as the spacecraft moves away from Earth (0.05-2.5 AU) demonstrating a peak 267 Mbps downlink at <0.37 AU.

The Deep Space Optical Communications (DSOC) project launched in October 2023 hosted by the Psyche spacecraft. The DSOC flight laser terminal will be periodically closing links starting a few weeks after launch and extending out to Mars ranges. The DSOC engineering model (EM) flight laser transceiver terminal was built to serve as a replica of the flight terminal in space to be integrated into an EM testbed at JPL. The EM testbed characterized the EM flight laser transceiver terminal under test conditions emulating deep space. These tests helped to understand acquisition, tracking, pointing and the bi-directional communications performance. The EM testbed includes a gravity offload structure and the Laser Test Evaluation Station (LTES) testbed that emulates the ground transmitter and receiver. The LTES testbed was developed at NASA/JPL to serve as a pseudo transmitter and receiver ground station for deep-space flight terminals. This paper will describe the EM testbed capabilities that provide calibrated uplink irradiances overfilling the 22 cm aperture, provides a zero-gravity environment, and characterizes the downlink beam. Atmospheric fading and additive background noise can be injected, while performing uplink/downlink communications characterization. The gravity offload is capable of injecting a disturbance spectrum with a hexapod system allowing for a range of spacecraft environments to be emulated. The LTES architecture can be expanded to allow for multiple flight terminals to be tested in parallel for future projects. Key DSOC validation and performance tests with the EM testbed are reported in this paper.

The National Aeronautics and Space Administration's (NASA) Deep Space Optical Communications (DSOC) payload, launched with the Psyche spacecraft on October 13, 2023, is facilitating an ongoing Technology Demonstration (TD) of Free-Space Optical Communications (FSOC), from beyond the earth-moon system. The DSOC Flight Laser Transceiver (FLT), can acquire a 1064 nm uplink laser from earth, and return a 1550 nm, Serially Concatenated Pulse Position Modulated (SCPPM) signal, to earth. The FLT uses a 22 cm diameter unobscured optical transceiver assembly, coupled to a 4 W average power laser transmitter, supplemented with actuators, sensors, electronics and software. A 5-7 kW average power, multi-beam 1064 nm uplink laser assembly integrated to the Optical Communications Telescope Laboratory (OCTL) near Wrightwood, CA serves as the Ground Laser Transmitter (GLT). The DSOC Ground Laser Receiver (GLR) at the Palomar Observatory, Hale telescope (operated by Caltech Optical Observatories), consists of a Superconducting Nanowire Single Photon Detector (SNSPD) array, connected to a ground signal processing assembly. Signal photon arrivals are detected and processed to extract information codewords at the GLR. A Mission Operations System (MOS) co-located with the Psyche Project Mission Operations Center, at the Jet Propulsion Laboratory (JPL), coordinates DSOC technology demonstration activities. This paper presents a system overview, mission description and operations architecture for the TD. Early results that include downlink at maximum downlink data-rate of 267 Mb/s from 0.37 Astronomical Units (AU) or 55 million kilometers are presented.

NASA is planning a bi-directional space-to-ground optical-communications detailed test object ive (DTO), from the crewed Orion spacecraft scheduled to fly on Artemis II. A space terminal element (STE) developed by MIT, Lincoln Laboratory, and NASA Goddard Space Flight Center (GSFC) is planned for flight on -board the Orion spacecraft. NASA GSFC will implement an Optical-to-Orion ground segment (O2O GS). One of the ground terminals (GT) servicing the O2O GS is planned at the Optical Communications Telescope Laboratory (OCTL) located at JPL's Table Mountain Facility, near Wrightwood, CA, while the other GT will be co-located with the O2O GS at the White Sands Complex (WSC), New Mexico. A functional description and development status of O2OGT TMF is pres ented in this paper. It is designed to support high photon efficiency (HPE) uplink and downlink signaling. The instrumentation of the O2OGT TMF will include (i) an optical assembly (OA) for interfacing laser signals to and from the OCTL telescope (ii) a beacon laser assembly (BLA) for transmitting modulated beacon lasers; (iii) an uplink laser assembly (ULA) for transmitting 10-20 Mb/s data to the STE (iv) a superconducting nanowire single photon detector (SNSPD) array for detecting the communications downlink (v) a ground signal processing assembly (GSPA) for processing the detected signal and extracting downlinked information codewords, as well as, measuring time of flight range and range rate (vi) a monitor and control (M&C) assembly for gathering and exchanging GT telemetry and (vii) a user gateway (UG) computer for interfacing user data to and from the O2O GS. Existing atmospheric channel monitor (ACM) at TMF will be used to gather and store weather and atmospheric data. The downlink will be received at discrete data-rates between 20 Mb/s and 260 Mb/s.

The Orion Artemis II Optical Communications (O2O) system will demonstrate the operational utility of laser communications for the first crewed Artemis mission scheduled to launch next year. O2O will provide an optical link with data rates up to 260 Mbps return from the moon and up to 20 Mbps forward to the moon. The optical link employs a Serially Concatenated Pulse Position Modulation (SCPPM) communications signal, compliant with the Consultative Committee for Space Data Systems (CCSDS) standard, and a modulated uplink beacon for acquisition and collaborative tracking. O2O employs optical ground stations located at the White Sands Complex (WSC) and Table Mountain Facility (TMF) to support the Earth end of the link. We describe interface testing performed between the space and ground terminals to verify the physical layer communication and beacon signals.

Laser sources for the NASA Deep Space Optical Communications (DSOC) technology transmitter and in the ground system for the uplink laser.

Power beaming involves the wireless transfer of power, and could provide a revolutionary new way to power spacecraft and vehicles operating in difficult to access regions. Power beaming has the potential to represent an alternative solution to power spacecraft and landers where sunlight is unavailable. It could provide a source of power to robotic systems in permanently shadowed regions or power landers and rovers from orbiting spacecraft (e.g.,Moon, Mars, Europa, Enceladeus, Miranda).

With NASA funding, the Deep Space Optical Communication (DSOC) Project at JPL is planning a system level technology demonstration of optical communications from deep space. A 22 cm diameter flight laser transceiver (FLT) is being developed for space flight. The FLT will be designed to transmit an average laser power of 4W at 1550 nm and receive a weak 1064 nm laser signal (> 100 femtowatts). Use of the Hale telescope at Palomar Mountain, CA, retrofitted with a photon-counting receiver to detect the downlink from space, is planned. The Optical Communication Telescope Laboratory (OCTL) at Table Mountain, CA will transmit a 1064 nm laser beacon to serve as a pointing reference for the FLT and support low-rate uplink data-rates. The DSOC FLT is part of the baseline payload for the Psyche mission spacecraft recently selected for flight by NASA, providing link demonstration opportunities during the mission cruise phase. Link demonstration opportunities at distances of approximately 0.1 to 2 astronomical units (AU) are expected. The DSOC system is being designed to support downlink data-rates of 0.2 to > 200 Mb/s and uplink data rates of approximately 1.6 kb/s. A status update of DSOC Project activities on flight and ground development will be summarized in this paper.

A master-oscillator power amplifier (MOPA) based 1550 nm wavelength fiber laser transmitter has been developed for Space-to-Earth communication application, utilizing Telcordia rated 1550 nm seed laser, pump lasers, and fiber optics. With adequate pre-screening of electrical components, the fiber laser transmitter has been in operation since its original launch in April 2014, for 30 months. This presents as a relatively cost-effective route for low-earth-orbit optical communication as well as LIDAR applications.

Optical Ground Station 1 (OGS1) is the first of a new breed of dedicated ground terminals to support NASA’s developing space-based optical communications infrastructure. It is based at NASA’s Optical Communications Telescope Laboratory (OCTL) at the Table Mountain Observatory near Wrightwood, CA. The system will serve as the primary ground station for NASA’s Laser Communications Relay Demonstration (LCRD) experiment. This paper presents an overview of the OCTL telescope facility, the OGS1 ground-based optical communications systems, and the networking and control infrastructure currently under development. The OGS1 laser safety systems and atmospheric monitoring systems are also briefly described.

A number of laser communication link demonstrations from near Earth distances extending out to lunar ranges have been remarkably successful, demonstrating the augmented channel capacity that is accessible with the use of lasers for communications. The next hurdle on the path to extending laser communication and its benefits throughout the solar system and beyond is to demonstrate deep-space laser communication links. In this paper, concepts and technology development being advanced at the Jet Propulsion Laboratory (JPL) in order to enable deep-space link demonstrations to ranges of approximately 3 AU in the next decade, will be discussed.

The Optical PAyload for Lasercomm Science (OPALS) experiment on the International Space Station (ISS) recently demonstrated successful optical downlinks to the NASA/JPL 1-m aperture telescope at the Optical Communication Telescope Laboratory (OCTL) located near Wrightwood, CA. A large area (200 μm diameter) free space coupled avalanche photodiode (APD) detector was used to receive video and a bit patterns at 50 Mb/s. We report on a recent experiment that used an adaptive optics system at OCTL to correct for atmospherically-induced refractive index fluctuations so that the downlink from the ISS could be coupled into a single mode fiber receiver. Stable fiber coupled power was achieved over an entire pass using a self-referencing interferometer based adaptive optics system that was provided and operated by Boeing Co. and integrated to OCTL. End-to-end transmission and reconstruction of an HD video signal verified the communication performance as in the original OPALS demonstration. Coupling the signal into a single mode fiber opens the possibility for higher bandwidth and efficiency modulation schemes and serves as a pilot experiment for future implementations.

Deep space optical communications places unique requirements on the laser transmitters. Recent developments for both a multi-Watt average power downlink laser source and candidates for a kW class uplink laser source will be discussed.

We report on the development, testing, and initial space qualification of a 1.5-mu m, high-power (6 W), high wall-plug efficiency (similar to 15%), pulse-position-modulated (PPM), polarization-maintaining, fiber laser transmitter subsystem for deep-space laser communication links. Programmable high-order PPM modulation up to PPM-128 formats, with discrete pulse slots ranging from 0.5 to 8 ns, satisfies variety of link requirements for deep-space laser communication to Mars, asteroids, and other deep-space relay links, as per the National Aeronautics and Space Administration's space laser communication roadmap. We also present initial space qualification results from thermal-vacuum tests, vibration testing, radiation testing, and an overall reliability assessment. (C) 2016 Society of Photo-Optical Instrumentation Engineers (SPIE)