In this project, a feasibility study for the PULSARS geostationary CubeSat system has been carried out. This involves the definition of a public protection and disaster relief use case using the satellite C-band, evaluation of a 16U CubeSat platform, and investigation into the spacecraft and ground segment technology required for coherent beamforming using a swarm of 20 independent spacecrafts. PULSARS mission design and system architecture are proposed, as well as a programme of technology development, enabling the spacecraft to operate for a minimum of three years. Remaining technological and regulatory challenges have been identified to validate the system concept further.