GB817056A - Improvements in or relating to radar simulators - Google Patents

Abstract

817,056. Analogue electric computing systems. MULLARD RADIO VALVE CO. Ltd. Oct. 23, 1956 [Nov. 1, 1955], No. 31268/55. Class 37. [Also in Group XL (c)] An electrical calculating system comprises apparatus generating signals corresponding to instantaneous range and bearing of a simulated aircraft. It is shown mathematically with reference to Fig. 1 that where X, Y are the cartesian components of ground velocity of the target; W, # the wind speed and bearing; Va, a the target's airspeed and heading; R, # the polar co-ordinates of the target referred to origin O. Va, α, #, W are set by manual controls 1, 2, 3, 4 respectively, Fig. 2, on linear potentiometers P 1 , P 2 , and resolvers S 1 , S 2 , so that voltages representing Va and W are applied from P 1 and P 2 to resolvers S 1 and S 2 which may be sine-cosine potentiometers or magslip resolvers. It is preferred to drive S 1 through a variable-speed motor to facilitate the setting of various rates of turn of an aircraft by the manual control. The outputs of S 1 and S 2 corresponding to Va sin α, Va cos α and W sin #, W cos # are applied, as shown, to summing circuits A 1 and A 2 to produce voltages X and Y respectively, these are fed to resolvers S 3 and S 4 , respectively, together with feed-back information corresponding to the instantaneous bearing # of the aircraft applied by means of a mechanical linkage. Produced voltages X cos # and Y sin # are applied to a subtracting circuit B to produce a signal representing R# and produced voltages X sin # and Y cos # are fed to summing circuit A 3 to produce R. Voltage R is then applied to an integrator circuit I 2 with an input voltage R 0 to produce a voltage R, this voltage R is fed to a divider circuit D with R# to produce voltage 6 which is applied with input voltage representing # 0 to integrator circuit I 1 to produce voltage #; R 0 , # 0 corresponding to an initial range and bearing of the simulated aircraft. Voltage # is fed to a gate signal generator G 1 , with a varying voltage from an aerial rotation simulator Ae so that when the angular position of the simulated aerial coincides with the angle 6 a pulse is supplied to gate circuit G 2 . Voltage R is applied to a phantastron delay circuit P to produce a pulse corresponding in time to the instantaneous range of the simulated aircraft, this pulse is applied to the gate at G 2 so that at coincidence with a pulse from G 1 a signal is supplied to the P.P.I. display unit which produces mark on the P.P.I. tube indicating the position of the simulated aircraft. The phantastron delay circuit is synchronized with the time base producing the radial sweep on the P.P.I tube. Several simulators M may be employed with a single display unit N.