Abstract: A length and velocity measurement apparatus based upon an interference pattern created between the amplitude modulation component of a transmitted signal, generated by an RF/microwave modulated continuous wave (CW) laser, and the amplitude modulation component of a signal reflected back from the target. The distance between the system and the target is measured by counting the periods in the interference pattern created between the amplitude modulation component of the transmitted signal and the amplitude modulation component of the reflected signal while the modulation frequency is swept from a frequency F.sub.1 to a frequency F.sub.2. In order to provide a fine adjustment of the apparatus, the apparatus may be mounted on a movable carriage to adjust the periods in the interference pattern to an integral number. Velocity measurements are made at a single frequency based upon the Doppler effect induced by the moving target.

Abstract: A system for introducing true time delays in a phased array antenna for pulsed signals comprising an active, recirculating delay time system which is selectively activated to introduce variable delays in the signal path between the signal transceiver and the individual antenna array elements.

Abstract: A pulsed radar system has improved signal to noise characteristics obtained by suppressing phase noise. Means are provided to store a copy of the transmitted RF signal pulse, which copy contains any phase noise of the RF carrier that is transmitted. The signal copy is retained and following a delay interval the signal is mixed in a high frequency electronic RF mixer with the received RF pulse signal, the latter of which represents a reduced level signal as reflected by an object back to the system receiver's antenna following the lapse of an interval of time. The RF mixer produces an intermediate frequency signal output in which the phase noise is suppressed thereby enhancing the receiver's signal to noise ratio. A novel pulsed signal delay circuit is employed in the foregoing which retains the copy by continuously recirculating a fraction of that RF input pulse over time until it is needed; as when the pulse is to be applied to the RF mixer.

Abstract: A combiner for power combining electromagnetic energy is disclosed. At least two electromagnetic cavities are positioned having intercavity coupling among all cavities: each cavity is tangent to all other cavities and/or external transmission line connections are employed to enhance/provide intercavity coupling. Each cavity contains within it at least one power generating device. An input/output port is connected via a nonreciprocal device to an output load and an injecting oscillator which usually has a lower power level than that of the free-running combiner and a higher spectral purity. The cavities are intentionally tuned to at least two different frequencies. For the two cavity and three cavity embodiments, a greater bandwidth is obtained compared with prior art combiners where the cavities are tuned to the same frequency. The power loss is slight.