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The patent describes a monopulse radar system which optically displays radar information 3-D for visual identification of targets. By visually displaying the radar target information in 3-D, the radar operator can quickly discern from its shape whether a particular target is a bomber, fighter, etc. and whether it is an enemy or friendly target. The system receives data from a high range resolution monopulse radar system having wideband monopulse tracking capability and processes it in a Display Processor so that its three outputs are representative of the three coordinate data information. The data is then displayed in a three coordinate display apparatus.

The acceptance test gain determination for the 29 foot diameter Cassegrainian antenna of the AN/FPQ-6 radar was performed by antenna pattern integration techniques. This approach was used because of time limitations and difficulties of setting up an accurate boresight range for conventional gain comparison with a gain standard. By pattern integration of both the antenna and the feed patterns, the effective loss of near-in sidelobes and the spillover around the Cassegrainian sub-reflector could be determined separately with good accuracy. This approach gives considerable information on several characteristics of the antenna which led, in part, to changes for improving antenna performance. The less significant losses were estimated. The resultant gain determined by this technique averaged at 51.1-db over the band. This was confirmed at a later evaluation program where direct measurement gave an average gain of 51.2-db over the band.

A proposed hull-mounted pro-submarine torpedo countermeasure is examined, which is an adaptation of an NRL-developed countermeasure against tracking radar systems. This device should be effective against all known types of active acoustic homing torpedoes and, modified, possibly against passive acoustic torpedoes. Its operation is based on the fact that the apparent position of any finite target of complex structure, as seen by a tracking system, will wander about the physical center of the target. This natural phenomenon is exploited by the countermeasure device so that the echo returned to the tracking system appears to come from a location many target spans away from the target. Preliminary experimental data indicate the feasibility of this technique as applied to sonar.

A graphical technique is described for obtaining the transfer characteristic, including phase, of a circuit or servo system from a time plot of the response to a unit step. The technique provides high accuracy in a few minutes of time using a graphical harmonic analyzer. In even less time the major features such as overshoot may be determined. Although computers have been programmed for this analysis, this technique can be performed with simple equipment that can readily be taken into the field to obtain on-the-spot analysis within the time that would have been required to read sufficient data points for a computer analysis. (Author)

Studies of microwave monitoring techniques have resulted in a potential method of monitoring of the percentage of sea water contamination to an accuracy of 0.25%. Investigation was made of both the dielectric constant and the dissipation (microwave energy loss) characteristics of contaminated fuel. The dissipation measurement gave the greater accuracy which improved with increasing microwave frequency. The dissipation measured for all samples of uncontaminated fuels was very small compared to the sensitivity to water, so that the effects of the differences in the different sources of fuel were minimized. Testing of samples from all parts of the world with accurately mixed percentages of sea water showed that this microwave technique can be used to monitor the percentage of sea water to within 0.25% of the actual value regardless of the source of the oil. The ability to measure to this order of accuracy was limited, in part, by the difficulty of preparing sufficiently precise sample mixtures for testing the technique. The microwave technique also lends itself readily to convenient practical implementation of continuous monitoring of fuel flowing to the furnaces. (Author)

The patent describes an apparatus for determining the water content of fuel oil. Microwave energy is directed through a chamber through which the fuel oil passes and a measure of the attenuation of the microwave energy is made. The attenuation of microwave energy as it passes through the oil determines the amount of water contamination within the oil. The system operates in the millimeter wave range where there is little attenuation caused by uncontaminated oil and a high attenuation caused by even small amounts of water contamination.