Abstract: A solar concentrator receives sunlight for generating solar power with the concentrator including holographic optical element (HOE) separators for separating sunlight into separated bands, including HOE concentrators for concentrating the separated bands into concentrated bands, including HOE reflectors for reflecting the concentrated bands as reflected bands onto a multiple junction photovoltaic solar cell for generating the solar power with reduced aberrations of the bands for improved conversion of the solar light into the generator solar power, all of which can be constructed in an integrated structure using spacers, waveguides, and a substrate, where the HOEs use chirp Bragg gratings for reducing optical aberrations of the separated, concentrated, and reflected optical bands, with the option of multiple HOE separators for receiving sunlight from various angles of incidence.

Abstract: An onboard solar cell array current and voltage characteristic determination method is preferably used on small spacecraft and determines the solar cell orientation relative to the sun by a comparison between prelaunch solar cell characteristics with on-orbit solar cell characteristics well suited for spin axis determinations and monitoring the degradation of on-orbit solar cells over the operational life of a picosatellite.

Abstract: A solar concentrator receives sunlight for generating solar power with the concentrator including holographic optical element (HOE) separators for separating sunlight into separated bands, including HOE concentrators for concentrating the separated bands into concentrated bands, including HOE reflectors for reflecting the concentrated bands as reflected bands onto a multiple junction photovoltaic solar cell for generating the solar power with reduced aberrations of the bands for improved conversion of the solar light into the generator solar power, all of which can be constructed in an integrated structure using spacers, waveguides, and a substrate, where the HOEs use chirp Bragg gratings for reducing optical aberrations of the separated, concentrated, and reflected optical bands, with the option of multiple HOE separators for receiving sunlight from various angles of incidence.

Abstract: An onboard solar cell array current and voltage characteristic determination method is preferably used on small spacecraft and determines the solar cell orientation relative to the sun by a comparison between prelaunch solar cell characteristics with on-orbit solar cell characteristics well suited for spin axis determinations and monitoring the degradation of on-orbit solar cells over the operational life of a picosatellite.