The radiation characteristics of the periodic dielectric grating antennas with various groove profiles are investigated by combining the multimode network theory with the rigorous mode matching procedure. As a result

the radiation calculations of the curved profile grating antennas are ended by the analysis of the multilayer rectangular periodic structure. In such a way

the effects of groove profile on the performance of the grating antenna are systematically studied and some useful guidelines for the design and fabrication of the dielectric grating antennas are thereby suggested.