
The Space Development Agency (SDA) is planning to launch 72 data-transport satellites in 2026, which will be part of the Tranche 2 Transport Layer Beta portion of a United States military mesh network. According to Frank Turner, SDA’s technical director, these satellites will have new and advanced capabilities, including direct-to-weapon communications. This represents a significant step forward in the development of military satellite technology.
The Tranche 2 Beta satellite order worth $1.5 billion was split between Lockheed Martin and Northrop Grumman, both of which had previously been awarded contracts for Tranche 1 Transport Layer satellites. SDA, an organization under the U.S. Space Force, is working on creating a mesh network of military satellites in low Earth orbit known as the Proliferated Warfighter Space Architecture. This network includes both a data transport layer and a missile-tracking sensor layer.
During the contract award process for Tranche 2 Beta, SDA received six bids. Turner mentioned that the agency would have preferred to involve more vendors, but the complexity of the mission and the specialized requirements, such as the need for advanced radios and waveforms for military tactical communications, limited their options. As a result, the selection of experienced Department of Defense (DoD) contractors was necessary.
SDA has expressed a desire to collaborate with a broader base of prime contractors and avoid favoring incumbents. However, due to the unique and complex nature of the payloads in Tranche 2 Beta, only a few companies in the industry possess the capabilities to meet these specific mission requirements.
The Tranche 2 Transport Layer Beta satellites are designed to integrate with radios using Ultra High Frequency (UHF) and S-band frequencies, which are essential for military and intelligence operations in the field. Additionally, each satellite is equipped with an Integrated Broadcast Service (IBS) payload. IBS is a legacy Department of Defense (DoD) network used to transmit tactical and strategic intelligence as well as targeting data from various sources. Typically, IBS payloads operate from geosynchronous satellites like the Mobile User Objective System (MUOS), which was developed by Lockheed Martin.
However, the challenge for the Transport Layer, according to Frank Turner of SDA, is to provide the same IBS service from low Earth orbit, which has never been attempted before. This is a complex task that involves developing the necessary technology and infrastructure to facilitate these communications from satellites in low Earth orbit, rather than the traditional geosynchronous orbit. Turner emphasized that this is a significant and challenging endeavor.
The primary goal of these capabilities is to fulfill the requirements and requests of the warfighter. They are looking for direct-to-weapon connectivity that can enable real-time engagements and communication with various assets in the field.
Furthermore, the Beta satellites will be tasked with establishing what Turner described as “extremely difficult” contacts with aircraft and missiles in flight. This indicates that the mission involves not only providing data connectivity but also facilitating real-time, dynamic communication and coordination with moving targets in the sky, adding an additional layer of complexity to the mission.
The Space Development Agency (SDA) is taking a commercial-like approach to build the Department of Defense’s (DoD) mesh network. This approach involves collaborating with a broad array of suppliers specializing in small satellites and laser communications terminals. SDA aims to create a flexible and diverse ecosystem of partners to meet its evolving satellite communication needs.
Frank Turner explained that the decision to choose two incumbent providers for Tranche 2 Beta was not taken lightly and was the result of extensive deliberation. SDA’s preference is to expand its supplier base and work with a wider range of contractors in the future.
SDA is actively engaging in discussions with military leaders to determine the necessary capabilities for Tranche 3 of the Transport Layer. This indicates the agency’s commitment to continually adapting and enhancing its satellite network to meet evolving defense requirements.
Currently, SDA is preparing for the launch of its second batch of Tranche 0 satellites and plans to commence launching 126 Tranche 1 satellites in September 2024. These Tranche 1 satellites will be equipped with inter-satellite optical links and are considered the infrastructure of the network. Tranche 2, which follows, will enable the network to support advanced communications capabilities, marking a significant milestone in SDA’s mission to create a robust and effective satellite communication system for the DoD.