. Airborne radar. Airplanes; Guided missiles. 9-9] ANGLE TRACKING LOOP MECHANIZATION 497 Transfer Function Pk> i o , - s2CjC2RiR^+.(C2Ri+C2R,+ Ci/!j) + i where R^= Ro(l+Kj Frequency Characteristic Design Formulas Let Ro= 1 (Resulting Values May be Adjusted to Any Impedance Level) Flow Diagram. Then: C,= 7j- + ,- '^1 cJcJ^ ) <^r R,c,co,u, Fig. 9-13 Active RC Tracking Network. General Design Considerations. In general, considerable care must be used in designing the track loop circuits. Proper grounding and shielding must be utilized to minimize ground loops and induced noise. Attenu
. Airborne radar. Airplanes; Guided missiles. 9-9] ANGLE TRACKING LOOP MECHANIZATION 497 Transfer Function Pk> i o , - s2CjC2RiR^+.(C2Ri+C2R,+ Ci/!j) + i where R^= Ro(l+Kj Frequency Characteristic Design Formulas Let Ro= 1 (Resulting Values May be Adjusted to Any Impedance Level) Flow Diagram. Then: C,= 7j- + ,- '^1 cJcJ^ ) <^r R,c,co,u, Fig. 9-13 Active RC Tracking Network. General Design Considerations. In general, considerable care must be used in designing the track loop circuits. Proper grounding and shielding must be utilized to minimize ground loops and induced noise. Attenuation and transfer function modifications due to impedance loading must be considered, especially in the summing networks where the gyro rate signal is added to the track loop. Adequate dynamic range must be provided in the amplifier to minimize the possibility of producing grid current and saturation due to large signal and noise inputs, especially during transient operation. It may be necessary to place Zener diodes across large capacitors to prevent voltages from accumulating at times when large step inputs are applied. At the stabilization summing point, a voltage sufficient to balance the large gyro voltage resulting from maximum antenna rates must be available from the angle track circuits. Finally, the tracking loop must be constructed and evaluated. This cannot be done satisfactorily until the actual antenna is constructed and used in the loop; ideally the measured antenna characteristics should be available in the initial design stages of the stabilization loop. After con- struction, the antenna performance, essentially its tracking accuracy, must be measured. Usually, as the result of preliminary measurements on the component parts of the system, the design may have to be modified to obtain the transfer functions desired. In airborne equipment it is important to measure the track loop performance over wide ranges of environment — pressure, temperature, and vibration
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Keywords: ., bookcentury1900, bookcollectionbiodiversit, booksubjectairplanes
