as their primary duty the radar. watch on board ships has revealed that 

 the use of anticiutter devices often times decreases the radar's effective- 

 ness due to lack of training or experience. It is known that vessels are 

 transiting the North Atlantic Ocean with the FTC circuit activated with- 

 out any knowledge of its function or use. Other vessels reduce sea return 

 by decreasing the video or receiver gain although STC is available on 

 the radar set. It is not too infrequently discovered that radio operators, 

 radar operators, merchant officers, and even naval watch officers do not 

 know the function of the anticiutter devices for their radar sets on which 

 they rely so heavily during reduced visibility. This lack of knowledge and 

 improper use of these devices leads one to the conclusion that in many 

 cases it is best not to have them available at all. In summary, we can 

 safely say that if an ice target is not picked up beyond the sea return it 

 will not be detected at all and a fatal collision might result. 



CONCLUSIONS AND DISCUSSION 



General 



It has been established by both observation and basic theory that an 

 intrinsic property of icebergs is poor electromagnetic reflection and that 

 reliance cannot be placed on radar for safe na ligation during moderate 

 sea conditions because if a dangerous ice fragment is not detected beyond 

 the sea return, it will not be detected at all. Below, the conclusions 

 reached for each topic of investigation are viewed and summarized in 

 relation to the following radar system parameters: 



Power Output 

 Receiver Sensitivity 

 Bandwidth 

 Frequency 

 Polarization 

 Antenna Rotation 

 Anticiutter Devices 



Power Output, Receiver Sensitivity, and Bandwidth 



We find that a reasonable approach to the assured detection of ice might 

 be to improve the system parameters to such an extent that all dangerous 

 ice targets can be detected beyond the sea return. This follows from the 

 fact that the rate of attenuation of sea return with range is greater than 

 that for a point target. Examination of the free space radar equation (2) 

 reveals that it is necessary to increase the power output 16 times in order 

 to double the maximum range of detection. This tremendous power in- 

 crease has been precluded in the past by considerations of cost and space; 

 however, recent developments in power generating devices* might allow an 

 improvement in the maximum range of detection without necessitating 



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