. The Bell System technical journal . (b) LOW- IMPEDANCE OUTPUT VOLTAGE \ T P ^ ^C--R-*^ RC(1+JLL) \ ! \Ec 1—^~ -^v^ \ / ■ TIME,t—^ Fig. 50.—Radar sweep generation circuits—^basic form and modified by negativefeedback to improve Fig. 51.—Circuit employed to improve linearity of sweep wave form b}- integrationmethod. A furtlier method of improving the linearity of the generated sweep waveform is illustrated in Fig. 51 where an additional correction voltage is super-imposed on the exponential sweep wave form. This correction voltage is THE RADAR RECEIVER 783 derived by integration of
. The Bell System technical journal . (b) LOW- IMPEDANCE OUTPUT VOLTAGE \ T P ^ ^C--R-*^ RC(1+JLL) \ ! \Ec 1—^~ -^v^ \ / ■ TIME,t—^ Fig. 50.—Radar sweep generation circuits—^basic form and modified by negativefeedback to improve Fig. 51.—Circuit employed to improve linearity of sweep wave form b}- integrationmethod. A furtlier method of improving the linearity of the generated sweep waveform is illustrated in Fig. 51 where an additional correction voltage is super-imposed on the exponential sweep wave form. This correction voltage is THE RADAR RECEIVER 783 derived by integration of the sweep wave form as impressed upon the ele-ments i?2, C2 and the voltage appearing across C2 is effectively superimposedupon the output wave form. As employed on an airborne bombing radarequipment, a circuit similar to that shown in Fig. 51, was employed where aresidual nonlinearity of less than was achieved and maintained undersevere military operating conditions. In certain instances it is desirable to generate a sweep wave form whichhas a specific nonlinear time characteristic. An illustration of one suchcase as applied to airborne radar is given in Fig. 52. Here the airborneradar display was required to present a nond
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Keywords: ., bookcentury1900, bookdecade1920, booksubjecttechnology, bookyear1
