Optical beamforming using chirped fiber grating: Criticality of group delay ripple

The effect of group delay ripple on optical beam-formers using chirped fiber grating is investigated in this paper. Optical beam-formers are promised to have many advantages over their electrical beam-forming counter-parts. However, mathematical analyses and simulation results have shown that the group delay ripple causes many limitations on the system performance, especially on the beam direction and directivity. As a result, the most advantageous feature of optical beam-formers using chirped grating, which is squint-free, has to be reconsidered.