Phased array antenna architectures - Using low-loss phase shifters

In this report, we summarize recent advances related to phased array architectures made in Europe and overseas. We analyse the performance of multifunction RFsystems using different architecture alternatives such as AESA (Active Electronically Scanned Antenna) and PESA (Passive ESA) and identify low-loss phase shifter as a key component for possible reduction of radar architecture cost, size, weight and DC power consumption for sense-and-avoid, SAR/GMTI and communication applications. More specific, starting from the system requirements for a Ka-band low-power multifunctional radar system for tactical UAVs we have identified key components and properties (such as phase shifter losses and DC-power consumption for low noise amplifiers) to be able to fulfil the specifications of such a multifunctional sensor system if realized using a PESA type of phased array architecture. Low phase shifter losses are found to be critical for the studied Ka-band low-power multifunctional radar sensor (to be able to arrive at a more affordable system solution). Furthermore, phase shifters using RF MEMS-based technology is expected to outperform todays commercial available phase shifters and hence fulfil the demands for low-loss phase shifting in applications such as low-power multifunctional radar sensors. Finally, a summary of preliminary results of fabricated hardware (RF-MEMS phase shifters and phased array modules) recently obtained within two international research projects in where FOI is participating is presented.