beam array scans the image field each position of the beam array is characterized by a pair of numbers j p where j is the receive focusing arc number and p is the line position of the array we adopt the convention where the line positions of the array are numbered consecutively from the left as follows p 0 1 p 1 where p n m unlike in a 1 beam system the number of lines in a multi beam system cannot be arbitrary in order not to have 34 holes 34 in a scanned sector and not to visit the same line twice the number of lines must be a multiple of u03b4 u00b7 m the beam array scans the image field as follows assume that at the beginning the beam array is in position 0 0 and the separation between beams is u03b4 transmit on all beams and receive the reflections from all arcs move the array one line to the right and transmit again continue until the line number of beam 0 is the same as the initial line number of beam i this means that beam 0 is about to scan a line that has already been scanned then jump to a new position such that the line position of beam 0 will be just to the right of the last line position of the beam m 1 and continue as described above we will refer to this scanning format as the scan and jump format with reference to fig2 and 4b it can be seen that each pulse transmitted along a line reflects a signal which contains.