NISAR L1 data products are in the original SAR geometry in range-Doppler coordinates.
The L1 Range-Doppler Single Look Complex (RSLC) product contains a focused SAR image providing amplitude and phase information.
Two L1 RSLC products, with the same footprint but acquired on different dates, are used to generate an L1 Range-Doppler Nearest-Time Interferogram (RIFG), a multi-looked interferogram ellipsoid and topographic phase flattened and formed with precise coregistration using geometrical offsets and high-resolution pixel offsets. Only nearest-neighbor pairs are processed; RIFG products with longer temporal baselines will not be automatically generated by the NISAR mission.
The L1 Range-Doppler Nearest-Time Pixel Offsets (ROFF) product provides unfiltered and unculled layers of pixel offsets with different resolutions obtained from incoherent cross-correlation.
The L1 Range-Doppler Nearest-Time Unwrapped Interferogram (RUNW) is the multi-looked unwrapped interferogram that is ellipsoid- and topography-flattened.