1. A method for detection of a moving object of approximately known size in conditions of low signal-to-noise ratio comprising: specifying a set of hypotheses (pairs: “azimuth-speed”) that describe all possible states of the object in a frame of data points representing a field of view; updating regularly the frame representing the field of view; smoothing, on each update, a brightness of data points of a new frame by replacing the brightness of each data point with an average brightness of data points surrounding this point and representing a hypothetical object; recalculating, on each update, an accumulated frame of each specified hypothesis as a sum of the accumulated frame of this hypothesis from a preceding update and the new smoothed frame shifted in accordance with a transfer of the object between updates; determining, on each update, a hypothesis that represents an actual state of the object the best as a hypothesis that produces the accumulated frame with a brightest point; displaying the accumulated frame of the best hypothesis after each update; determining a moment when the object is detected as the moment when the best hypothesis stabilizes in a sequence of updates and a movement of the brightest point in a screen becomes consistent with the azimuth and speed of this hypothesis; reporting coordinates of the object, its azimuth and speed to a surveillance system.