An incoherent imaging of a conducting cylinder illuminated by the time-harmonic plane wave is obtained via the backprojections of the incoherent intensity patterns, which is acquired by averaging out the multifrequency intensities of the total field scattered from this object in the circular rotational measurement configuration. The multi-frequency effect is shown numerically, and is interpreted analytically by the mutual coherence function defined in the frequency domain. This imaging method is validated by imaging circular and elliptic conducting cylinders, and the conditions for obtaining better images are investigated. (C) 1998 John Wiley & Sons, Inc.