90° hybrid 90°-hybrids 1 Common mode rejection ratio 1 Common-mode rejection ratios 1 Errors 1 Fabrication 1 Fabrication error 1 Fabrication errors 1 III-V semiconductors 1 InP monolithic integration 1 Indium phosphide 1 Monolithic integrated circuits 1 Monolithic integration 1 Monolithics 1 Optical 90° hybrid 1 Performances analysis 1 Phase error 1 Photodetectors 1 Photons 1 Semiconducting indium phosphide 1 Spectral response 1