Abstract: A system for generating a simulated radar return signal. The novel system includes a processor adapted to receive target and waveform parameters and in accordance therewith generate a composite digital signal, and a digital to analog converter adapted to convert the digital signal to an analog signal. The system also includes an upconverter adapted to convert the analog signal to radio frequency. The processor calculates time-domain digital data samples representing a composite radar return waveform based on the target and waveform parameters. These data samples are output at each time interval that the digital to analog converter samples data. The composite waveform can include returns from a large number of targets and from targets embedded in clutter. The system can also be adapted to test a radar system having multiple antenna ports by replicating the basic design for each port.

Abstract: An automated simulator for radar and sonar applications. The inventive simulator is implemented in hardware and generates current parameters with respect to a simulated target in response to a plurality of initial values with respect thereto. In the illustrative embodiment, the initial values include range, velocity, and acceleration and are stored in first, second and third register respectively. In the best mode, the invention is implemented in a field-programmable gate array. The inventive target simulator also includes a range delay circuit for generating a simulated return from the simulated target. The range delay circuit includes logic for determining whether a simulated pulse train to be received is ambiguous or unambiguous and adjusting the pulse repetition rate of the pulse train accordingly. The range delay circuit calculates die initial time that a packet needs to make the trip to and from the target.

Abstract: A radar target simulator for generating simulated targets used in testing a radar system. Simulated targets are generated out of the radar system noise. The radar system includes a radar receiver coupled to a receive antenna. The simulator has an input for sampling a transmitted output signal from the radar system. A first reference oscillator is provided for generating a first reference signal, and a first mixer is coupled to the first reference oscillator for mixing the first reference signal with the sampled signal from the radar system to provide a simulated target signal. A laser is coupled to the first mixer for generating a light output signal that corresponds to the simulated target signal. A plurality of selectable delay paths that each have a different predetermined delay length are coupled to the laser. A photodetector is coupled to the plurality of delay paths for convening the light output signal derived from a selected one of the delay paths into a radio frequency (RF) simulated target signal.

Abstract: A programmable fiber optic delay system employs multiple programmable fiber optic delay lines, and switches among the delay lines for inclusion in an overall delay path. Switching among the delay lines is coordinated with the programming of those lines so that only a delay line with a settled delay program is included in the overall delay path. Each delay line consists of a plurality of fiber optic segments of varying length. The line's delay is programmed by switching in particular segments whose aggregate lengths correspond to a desired delay period. The multiple delay lines are used to simulate target speed and distance for use in testing a radar system. The programming of each individual delay line and the switching between lines is preferably controlled by a computer resident in the target simulator.