The project GUARD has studied different issues in the field of phased array antenna based radar systems with perspectives on different system levels. Generic radar systems have been developed and analyzed. The work has then been supplemented with studies of new antenna concepts and key technologies considered to be interesting for present and/or future systems. During the period 2015-2017, the project has further developed knowledge and analytics in the area of phased array antenna based radar systems. The aim has been to cover both the width and the depth of the area. The former is maintained through overview analyses made in our internal assessment work. The depth is retained through experimental work in narrower focus areas (such as creation of a downward 3D-SAR system and a radar for UAV) but also through the research-oriented work carried out in the co-financed projects. The project has described and developed application examples for phased array antenna based radar systems. A survey has been made of the results and benefits of cofinanced projects. The 3D-SAR concept has been further developed and a preliminary study on the development of a radar sensor for a smaller UAV has been initiated. During the project period, the project has contributed with the required knowledge to the FMV-funded project Network Based Air and Sea Surveillance (NBASS), where FOI contributes expert support prior to the acquisition of a new Swedish sensor chain. We can thus see that our long-term knowledge acquisition in the field of phased array antenna technology is beneficial, both at the component - and subsystem level as well as at the system - and signal processing levels. Through collaboration with co-financed projects, it has been possible to increase the depth of GUARD. Examples include development of a phased array antenna for detection of people in rubble (EU) and development of technology for systems that can see through clothing (SSF) and technology for sensors that can be used in anti-collision systems, aircraft landing aids and helicopter safety sensors (Vinnova and SSF). In summary, the project has contributed to further development of our existing knowledge in the field of phased array antenna technology, in order to assist the Armed Forces with knowledge in the field.