  The Fourier transform spectrometer (FTS) is a core instrument for solar
observation with high spectral resolution, especially in the infrared. The
Infrared System for the Accurate Measurement of Solar Magnetic Field (AIMS),
working at 10-13 $\mu m$, will use a FTS to observe the solar spectrum. The
Bruker IFS-125HR, which meets the spectral resolution requirement of AIMS but
just equips with a point source detector, is employed to carry out preliminary
experiment for AIMS. A sun-light feeding experimental system is further
developed. Several experiments are taken with them during 2018 and 2019 to
observe the solar spectrum in the visible and near infrared wavelength,
respectively. We also proposed an inversion method to retrieve the solar
spectrum from the observed interferogram and compared it with the standard
solar spectrum atlas. Although there is a wavelength limitation due to the
present sun-light feeding system, the results in the wavelength band from
0.45-1.0 $\mu m$ and 1.0-2.2 $\mu m$ show a good consistence with the solar
spectrum atlas, indicating the validity of our observing configuration, the
data analysis method and the potential to work in longer wavelength. The work
provided valuable experience for the AIMS not only for the operation of a FTS
but also for the development of its scientific data processing software.
