Tactical Microsatellite Experiment (TacSat-1)

M. Hurley
Spacecraft Engineering Department

Introduction: The DOD's Office of Force Transformation (OFT) and the Naval Research Laboratory are working on the development of and experimentation with a tactical microsatellite system, with emphasis on producing operationally relevant capabilities. Touchstones of this system include: quick response, Joint Task Force (JTF) organic, selectable payloads, coverage for military conflicts and opportunities at any location on Earth, and an unmanned aerial vehicle (UAV) class of cost. This system ultimately integrates space assets into the forces such that the JTF Commander can call up the assets by deciding the payload capability needed, the area of interest, the area for direct downlink, and the date to call-up the assets. Once deployed, the space assets are directly tasked via the SIPRNET, which is also used to distribute the collected data and products.

TacSat-1 has several payloads that provide capabilities for cross-platform missions, specific emitter identification, and visible and infrared (IR) imaging. TacSat-1 is currently under construction and is scheduled for an early 2004 launch, a schedule that is less than 1 year from the sponsor's go-ahead. To meet this timeline and the challenging budget, many different technical and programmatic approaches are being implemented. This article provides a top-level overview of the experiment and some approaches being used to perform the experiment.

Background: During the second half of 2002, NRL studied the tactical application of space assets. Relatively new technologies and processes in the areas of micro-satellites, affordable and quick-response launch vehicles, and the classified SIPRNET (Secret Internet Protocol Router Network) make tactical use of space assets possible in the relatively near term. OFT agreed with the core findings of the study and decided to start an Operationally Responsive Space Initiative consisting of a series of experiments. TacSat-1 is the first experiment in this OFT initiative. The TacSat-1 experiment received go-ahead on May 7, 2003 and is scheduled to launch within 1 year of this date.

TacSat-1 Objectives: One of the objectives of TacSat-1, as well as the broader initiative, is to make space assets and their capabilities available to operational users. Additionally, OFT intends for the TacSat-1 experiment to generate policies where concepts and technology co-evolve, ultimately ensuring that space-based assets emerge as an organic part of the JTF.

The overarching objective of this experiment is to provide and launch an operationally relevant micro-satellite (Fig. 1), with the ability to task and disseminate data through existing operational networks (SIPRNET), in less than 1 year and for less than $15 million (to include launch costs). Additionally, this experiment will explore concept-technology pairings that develop near-term paths for the tactical use of space in four key areas.

Figure 1 Image
TacSat-1 spacecraft.

In the area of micro-satellite design and processing, the TacSat-1 schedule and low cost are pushing intelligent applications of standard processes as well as new design and test approaches. One of the new approaches includes utilization of unmanned aerial vehicle (UAV) components within a hermetically sealed, fan-cooled chassis, to help them survive and operate in space.

The TacSat-1 experiment will provide one data point in the area of responsive, on-demand space lift. The experiment uses a new, commercial launch vehicle (the Falcon Launch Vehicle) being developed by Space Exploration technologies with private capital to compete within dynamic market conditions. During the TacSat-1 launch preparation, tailored DOD approaches to mission assurance and risk mitigation are being developed to be appropriate for the rapid cycle times and low-cost class of micro-satellites missions.

The TacSat-1 space element will be used in operational experiments, showing a way for space assets to become an organic part of the JTF. Direct tasking and data dissemination are being performed both real-time from aircraft and time-latent (based on orbital positioning) via the SIPRNET (Fig. 2).

Figure 2 Image
Blossom Point ground station connected to tactical users via SIPRNET.

Finally, TacSat-1 will help the development of space professionals and the processes needed for responsive space. An important aspect of this is the strong government-industry team implementing TacSat-1. This largely in-place team allows the entire experiment to be defined and implemented faster than most contracts can be put in place. This government-industry team approach also helps to spread the knowledge gained from TacSat-1 into industry as well as within the government.

Payload Capabilities: TacSat-1 payloads will provide several experimental capabilities. Machine-to-machine collaboration between air and space assets (Fig. 3) for geo-location is one of the payload capabilities. This capability has the potential to path-find future national capabilities and concepts of operation (CONOPS). This payload is a deviation of NRL's Spacecraft Engineering Department payload development that has been done for the Navy TENCAP (Tactical Exploitation of National Capabilities) and a CONOP extended from an ONR program.

Figure 3 Image
Space-to-air asset collaboration.

A specific emitter identification (SEI) payload is another capability. This payload is a Tactical Electronic Warfare Division (TEW) development that has been repackaged for space. Both the SEI and cross-platform mission payload also leverage the TEW Low Cost Receivers (LCR-100) design, which is an enabling micro-satellite technology because of its impressive capability yet small size, weight, and power.

Two imaging cameras have been included to provide intuitive data for the SIPRNET tasking and data dissemination part of the experiment. One camera is an infrared camera (Fig. 4) that uses a microbolometer FPA, which does not require cryogenic cooling, thereby significantly reducing complexity (size, weight and power). This IR camera is a product of an Army Night Vision Laboratory development and was recommended for flight by TEW. The IR camera collects in the 7.5 to 12-µm range and will provide 850-m resolution. A visible camera is also installed and will provide 70-m resolution.

Figure 4 Image
IR omega camera by Indigo.

Key Partnerships: Many partnerships have been made to achieve this experiment within the schedule and cost. Some of the key partnerships and roles are discussed here. The Naval Research Laboratory is the program manager, integrator of the micro-satellite, and responsible for the TacSat-1 mission design and implementation. Air Force Space Command, Space and Missile Center (SMC) is providing mission oversight for the booster, and the 30th Space Wing is providing the launch facility and launch services, and operates the Western Range in support of the launch. TacSat-1 capitalizes on NASA's Virtual Mission Operations Center (VMOC) for SIPRNET payload tasking and data dissemination. VMOC is also being adopted, and experimented with, by the Air Force Space Battlelaboratory and the Army Space & Missile Defense Command Battle Laboratory for a spacecraft/NIPRNET (Nonclassified Internet Protocol Router Network) interface. The Blossom Point Ground Station is providing satellite command and control as well as SIPRNET-based payload tasking and data dissemination using a tailored version of VMOC. The NRO Office of Space Launch is providing the payload processing facility at Vandenberg Air Force Base. Regional Combatant Commanders are providing operational experimentation and coordination. The SpaceX Corporation is on contract for the launch of TacSat-1 aboard the inaugural flight of their Falcon Launch Vehicle (Fig. 5).

The result is an impressive team of organizations all working to ensure the success of the TacSat-1 experiment.

Figure 5 Image
Falcon launch vehicle.

[Sponsored by OFT]