We analyze a circular array of electric line sources for generating a uniform plane wave in the interior region of the array. Identical results for the synthesized element weightings are obtained using matrix inversion or a Fourier series technique. A physical optics approximation for the element weightings is also presented, hut it yields a much poorer result for the synthesized field. The angle of arrival of the plane wave can be scanned by recalculating the element weightings, and the quality of the field is maintained. Frequency scanning is also possible, but the number of array elements limits the maximum frequency, Key Words-Plane-wave synthesis, uniform plane wave, antenna array. Index Code-AZd, I7d.