Estimate of the fourth-order coherence function by a spatial convolution method and its potential applications in laser information systems

It is shown that the coherence function of the radiation scattered by an object with a Lambert surface can be determined by a method of spatial convolution of the intensity field. The results obtained by this method are not affected by time instabilities of the radiation from a transmitter. A method is suggested for measuring the angular radius of a lidar object and an estimate is given of the potential precision of the method.