Development of a Molecular Assessment High-Resolution Observation Spectrometer (MAHOS) for Microsatellites

Compact and lightweight sensors with a high-frequency resolution are required for the passive observation of atmospheric water and oxygen emission lines at a reduced cost and power consumption. A molecular assessment high-resolution observation spectrometer (MAHOS) is developed as a compact, low power, digital fast Fourier transform spectrometer to be installed on a microsatellite. MAHOS has a compact design with dimensions of
$0.154\times 0.125\times0.040$
m
³
and mass of 0.7 kg. It uses only a few materials including a field-programmable gate array (FPGA) module with a lightweight aluminum alloy box. The highly stable spectrometer exhibits a sampling speed of 2.6624 GS/s and 16 384 frequency channels. The stability of the spectrometer is longer than 1200 s within the 1-GHz bandwidth. Thermal dissipation is achieved through a heat conductive gel filled in the gap between the most heat-generating component, the FPGA, and the aluminum alloy case. Results of a finite element analysis indicate that the design is stiff and stable enough to survive in the launch environment. Thermal analysis indicates the durability of the system during operation. Even in space where heat dissipation is not possible, self-heating temperatures are not a problem for the FPGA. In the future, the performance of the spectrometer will be verified by conducting environmental tests.