Understanding the distribution characteristics of atmospheric components and parameters at different altitudes plays a crucial role in deeply comprehending climate change and addressing climate issues. To meet the detection requirements for vertical profiles of multiple atmospheric components (H2O,CO2,CH4,N2O,O3,CO, etc.) and line-of-sight wind speed, this study designs an LEO-LEO infrared laser occultation (LIO) system. For payload design, the laser transmitter employs broadband frequency-locked laser source technology to generate highly stable infrared lasers. The receiver utilizes multi-grating spatial heterodyne spectroscopy (SHS), achieving wide spectral coverage (2-2.5 μm) and high spectral resolution (≤0.15 cm-1). For data application and orbit simulation, an Abel transform-based inversion method is proposed to synchronously retrieve atmospheric composition and parameter profiles in the Upper Troposphere and Lower Stratosphere (UTLS). Additionally, a simulated occultation orbit system demonstrates a daily occultation event frequency of up to 61 times, with optimized data acquisition processes for single events.