ANTENNA MEASURING METHOD

PURPOSE:To measure the exciting amplitude and phase of each element of a phased array antenna in a short time. CONSTITUTION:The phase of a phase shifter 2 for an element antenna 1 is set M times between O to 2pi radian at a constant interval, e.g. 2pim/M (M: a natural number depending on the form of the phase shifter, m=O, M-1). An amplitude/phase receiver 7 measures the amplitude and the phase of combined radiation field of the phased array antenna to determine a complex combined field vector Em. M measurements of complex combined field vector Em are then multiplied by exp (-j2pim/M) (exp: exponential function, j =-1) and an arithmetic average of M products of Em.exp (-j2pim/M) is determined thus obtaining the exciting amplitude and phase of a relevant element.