MarconISSta

Radiofrequency spectrum for satellite operation is a scarce resource. Along with the increasing number of launched and upcoming small satellites, the potential of harmful interference rises. In particular in UHF bands, small satellites are launched and operated at very low costs and therefore higher repetition rate than traditional systems. This evolvement puts pressure on existing allocations for amateur-satellite and space operation services. For this reason, a payload is introduced to measure the spectrum use in orbit and to assist in the identification of potentially free frequency allocations to ease the current coordination environment.

MarconISSta (from marconista, Italian for radio amateur) is an  ISS experiment to measure spectrum use, interference potential and to support sharing studies in the crowded frequency spectrum allocated to satellite communication. The experiment is based on readily available COTS (Commercial Off-The-Shelf) hardware that is only slightly modified to withstand the space environment.

MarconISSta was integrated into the existing ARISS setup and uses the ARISS antennas on the Columbus module. The experiment was conducted during ISS expedition 56/57 in 2018/19. On February 9th 2019 the system was deinstalled. Currently, data analysis is performed, while a second experiment is planned for late 2019/ 2020.

Objectives

• Analysis of spectrum use in UHF in the ranges 435-438 MHz
• Analysis of spectrum use in VHF in the ranges 145.8-146 MHz
• Analysis of spectrum use in L Band in the range 1260-1270 MHz
• Analysis of spectrum use in S Band in the ranges 2400-2450 MHz
• Detection of interferers using algorithms based on received signal strength, attitude information, frequency Doppler shift information and antenna gain pattern
• Assessment of ARISS antenna radiation pattern