Described embodiments include an electromagnetic beam steering apparatus. The apparatus includes a first blazed transmission diffraction grating component configured to angularly deflect an electromagnetic beam at a first blaze angle. The apparatus includes a second blazed transmission diffraction grating component configured to angularly deflect an electromagnetic beam at a second blaze angle. The apparatus includes an electromagnetic beam steering structure configured to independently rotate the first blazed transmission diffraction grating component and the second blazed transmission diffraction grating component about a coaxial axis such that an electromagnetic beam incident on the first blazed transmission diffraction grating component exits the second blazed transmission diffraction grating component as a steered electromagnetic beam.