Proliferated Warfighter Space Architecture (PWSA)

The Proliferated Warfighter Space Architecture (PWSA) is a US Department of Defense space program led by the Space Development Agency (SDA) to deploy a large, resilient constellation of low Earth orbit (LEO) satellites to support military communications, missile warning and tracking, and data transport. The architecture was known prior to early 2023 as the National Defense Space Architecture (NDSA).

PWSA is based on a proliferated design philosophy, using hundreds of relatively small, lower-cost satellites rather than a small number of highly capable but vulnerable spacecraft. The system is intended to augment existing military satellite constellations and is widely viewed as a future space-based communications backbone for Joint All-Domain Command and Control (JADC2), enabling data sharing and coordination across land, sea, air, space, and cyber domains.

The architecture is being developed using a rapid spiral or tranche-based approach. Tranche 0 consists of 22 transport satellites equipped with optical inter-satellite links and 8 missile tracking satellites. Tranche 1, planned for initial deployment from 2024, includes 126 transport satellites and 35 missile tracking satellites, while Tranche 2 is planned to expand the system further with approximately 250 transport satellites and 54 tracking satellites.

The SDA has demonstrated key elements of the concept, including the transmission of Link 16 tactical data from Tranche 0 LEO satellites at altitudes of around 2,000 km to ground users, illustrating the potential for direct connectivity between space-based sensors and operational military networks. These demonstrations highlight both the promise of the architecture and the regulatory challenges associated with transmitting certain military waveforms from space.