This reference file contains the minimum number of IFGs needed to form templates in each channel (RH, RL, LH, LL). It is used by FIL.
In order to facilitate the taking of a median if necessary, the minimum
number of IFGs should be an odd number. We fear that 3 is too small because
any statistical quantities generated from that number are likely not to
be meaningful. Seven is uncomfortably large because our proliferation
of operating states during the mission will probably cause there to be
a significant number of pixels with fewer than 7 coaddable IFGs. Thus,
we compromise on 5.