Design of an FPGA-based high-speed filter-decimator for the GIFTS imaging interferometer

This paper presents the design of an FPGA-based frame filter-decimator for the geostationary imaging Fourier transform spectrometer (GIFTS). The decimator reduces samples from two 128/spl times/128 sample imaging arrays from 1638.4 fps to 102.4 complex fps for the long wave IR (LWIR) band and from 1638.4 fps to 204.8 complex fps for the medium wave IR (MWIR) band. The design uses a novel parallel pipeline architecture to handle the bandpass sampling and decimation of the 16 k array samples which arrive a frame-at-a-time. The design is challenging because of significant speed, size, weight and power restrictions for satellite implementation.