Abstract: A time varying excitation current (413) is provided to one side of a capacitive sensor (417), and two signal paths (420,430) are provided between the other side of the capacitive sensor (417) and signal conditioning circuitry (412), each signal path differing from the other according to its polarity. The signal paths conduct monopolar signals from the capacitive sensor the magnitude of which are directly related to the capacitance of the sensor, and bi-polar signals the magnitude of which are directly related to the stray capacitance in the signal lines. The combined monopolar and bi-polar signal currents on each signal line are converted into voltage signals (422,433), and the voltage signals are thereafter differenced (460) to provide a null bi-polar output while providing a constant monopolar voltage level the magnitude of which is directly related to the probe capacitor current.

Abstract: A vehicle mounted radar system has an antenna (12) which rotates about a reference axis (19). During angular movement of the antenna with respect to the reference axis, a radar indicated target azimuth (.phi.') is modified to provide a corrected target azimuth (.phi.) which is substantially indicative of the actual or true target azimuth. A tracking system (25) uses a predicted radar indicated target position (P.sub.n+1 (x,y)) for target tracking and correlation. The tracking system uses a smoothed target position (STP(x,y)), indicative of actual target position, for providing a visual display (39) of target track.

Abstract: A TWT energizing circuit for compensating for the voltage droop at a TWT hode comprising the use of a differential amplifier which takes a modulation pulse at one of its inputs and a feedback signal comprising a sample of the body current from the TWT helix at the other of its inputs and applies a signal representative of the difference therebetween to the TWT grid. The above-described feedback circuit forces the grid voltage to track the cathode voltage thus maintaining a constant grid-cathode voltage drop.

Abstract: Phase dispersion between two or more traveling wave tubes (TWTs) is corrected on a pulse to pulse basis by a feedback loop which compares the relative phase of RF signals to be amplified in traveling wave tubes with one another, and provides a phase correction at the input to at least one of the traveling wave tubes such that the phase difference at the output of traveling wave tubes is the same as the phase difference at the inputs thereto, except for any offset therein which may be purposely inserted as desired. The phase difference at the input and at the output is achieved by phase correlators feeding sample and hold circuits, the outputs of which are converted from rectangular coordinates to polar coordinates including an angle; the phase difference angle at the input being compared with the phase difference angle taken from the output.