A pod with a very long broadband time steered array antenna for PAMIR

A reconfigurable pod-mounted antenna frontend configuration for the PAMIR SAR/GMTI imaging radar, an experimental active phased array system with a very high instantaneous bandwidth of 1.82 GHz in X-band is described. The pod accommodates a linear time and phase steered array antenna with a length of 4.25 m. Broadband beamforming together with wide azimuth scan capabilities (=± 45deg@1.82 GHz bandwidth) requires a switchable true time delay network with time increments equivalent to a fraction of a wavelength. The subarray structure including the time delay components and the total array performance are described. PAMIR serves as an ideal airborne platform for future broadband SAR/GMTI research activities including interferometric image formation.