Performance investigation of a homing guided missile with positioning the seeker antenna

One of the main elements constituting a homing guided missile is the seeker or homing head, which consists mainly of an antenna (or detector) with a servo-tracking loop. The positioning of this antenna and its philosophy of operation affects seriously the speed with which the missile responds to guidance commands. Thus, this paper is devoted to analyze the performance of three proportional navigation guidance systems installed in a given supersonic, variable-incidence, boost-glide, antiaircraft missile at Mach numbers of 2.7 and 1.3. These guidance systems differ in the method of positioning the seeker antenna relative to a coordinate system fixed in space. The comparison is carried out on a basis of the maximum obtainable speed of the missile response and guidance-system combination consistent with adequate stability. The obtained results show that, with the antenna stabilized in space, the effect of component lags on the response is small, so that the speed of response can be made to approach closely that of the airframe alone. Conversely, if the antenna is not stabilized in space, the speed of response is limited by stability considerations of the missile and guidance-system combination. By including compensating networks, it is possible to obtain performance comparable to that of the system with the antenna stabilized. However, the response is relatively sensitive to small variations in network time constants and to missile flight-speed variations.