Abstract: A tracker for predicting the occurrence of an arbitrary number of phase coherent signals comprising a signal train, which predicts the phase and pulse repetition intervals for each individual signal and which maintains phase coherence of all signals provided at least one signal is present. A multiplexing system permits tracking of a multiple of phase coherent signal trains by successively connecting a series of tracker channel memories with the phase and pulse repetition interval error correction circuitry required for a single tracker. Each channel maintains phase coherency for all signals of its associated signal train while at least one signal of the train is present.

Abstract: A noise generator that is responsive to digital noise quality and noise modulation input signals to provide a controller noise signal to a voltage controlled oscillator. The noise generator adds a center frequency input signal, a weighted random noise signal, and a weighted wobbulated waveform signal to obtain a controlled digital noise signal and converts this noise signal from digital form to analog form to provide a noise generator output signal that controls the voltage controlled oscillator. The center frequency and modulation of the noise generator output signal spectrum are determined by the center frequency and weighted wobbulated waveform signals, respectively, and the range of the output signal spectrum is determined by the weighting of the random noise signal. A ramp input signal, which is converted from digital to analog form, is integrated and added to the noise generator output signal to further define the quality and range of the output signal spectrum.

Abstract: A D/A conversion circuit has each branch of its resistive binary scaling network energized by a switchable network. Each switchable network employs the internal current paths of an Integrated Circuit (I.C.) solid state device, such as a Complementary-Metal-Oxide Semiconductor-Field-Effect-Transistor (CMOSFET) device, which provides complementary switching action. Each switchable network also employs a Metal-Silicon (M-S) diode, which provides clamping and diode switching actions. By a combination of I.C. device and M-S diode device actions, the following features are achieved in a single circuit: (A) high accuracies, (B) fast setting times and (C) low power consumption. Also disclosed is a cooperating variable D/A reference potential source which achieves temperature compensation.