Abstract: A system and method is disclosed that provides a means for the high efficiency low distortion amplification of complex modulated radio frequency signals, such as but not limited to Single Side Band (SSB) signals. The innovative principle of the invention is based on the simultaneous amplitude and phase or angle modulation of Class "C" amplifier. Complex signals such as SSB signals can be described as a combination of amplitude and phase or angle modulation. By determining the amplitude and phase or angle components of the complex signal and using these to modulate a Class "C" amplifier, according to the manner prescribed in the invention, the objective of high efficiency low distortion is achieved. Previously, Class "B" amplifiers were required to amplify complex RF signals. The maximum efficiency of a Class "B" amplifier typically achieved in practice is about 40 percent compared to about 85 percent for Class "C" amplifiers.

Abstract: A tracking servo compensator is disclosed for radar systems which steer their antenna beams using a servomechanism that physically moves the antenna. The disclosed tracking servo compensator permits switching between trackers (e.g. from area to point track) and from one tracked target to another without undesirable transients that could cause loss of track. Rate aiding and target range estimates are provided when tracker base motion is known. The compensator works by providing a servo signal that continually monitors the error in estimated track point line-of-sight angular velocity independent of which tracker is employed or the target being tracked. When base motion is known, this signal is used to update the target range estimate so that an accurate rate aiding signal is available. The servo provides smooth controlled-speed transitions between track points during mode switching, and provides an input for manual slewing of the tracker platform during offset track conditions.

Abstract: The obtaining of simultaneous pulse-to-pulse transmitter carrier frequency agility and compatible moving target indicator (MTI) operation in conventional surveillance radars is achieved by the use of pairs of frequencies with a controlled relationship between the frequencies of each pair. A set of four pulses with different frequencies is sequentially transmitted and form two pairs of pulses. The difference between the frequencies of one pair of pulses is made equal to the difference between the frequencies of the second pair of pulses. MTI operation is obtained by differencing the pairs. Pulses having any three frequencies may be selected in any sequence before a constraint is imposed. The frequency of the fourth pulse is then determined by the frequencies of the first three pulses.