In this paper, radiation characteristics of the perfectly superconducting, or an imperfectly conducting rectangular microstrip, which is printed on isotropic or uniaxial anisotropic substrate are investigated using a Fourier transforms domain in conjunction with the stationary phase method. The effects of uniaxial anisotropy on the resonant frequency, half-power bandwidth, and radiation patterns are investigated as the function of anisotropy ratio values of substrate materials. It is found that the resonant frequency and the half-power bandwidth are affected significantly by the superconductivity property of the patch. Further results show that a thin superconductor patch has a significant effect on the radiation pattern. Results are compared with previously published data and are found to be in good agreement.