Wireless telecommunications represent an important asset for public protection and disaster relief (PPDR) organizations as they improve the coordination and the distribution of information among first responders in the field. In large international disaster scenarios, many different PPDR organizations may participate to the response phase of disaster management. In this context, PPDR organizations may use different wireless communication technologies; such diversity may create interoperability barriers and degrade the coordination among first-time responders. In this paper, we present the design, the integration, and the testing of a demonstration system based on software-defined radio (SDR) technology and software communication architecture (SCA) to support PPDR operations with special focus on the provision of satellite communications. This paper describes the main components of the demonstration system, the integration activities as well as the testing scenarios, which were used to evaluate the technical feasibility. The paper also describes the main technical challenges in the implementation and integration of the demonstration system. Finally, future developments for this technology and potential deployment challenges are presented.