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BELL SYSTEM TECHNICAL JOURNAL 



D. Presentation of all desired information to the observer in a form cap- 

 able of immediate analysis and use. 



With these functional requirements in mind, it is in order to examine the 

 character of the information available at the input and that required at the 

 output terminals of a radar receiver. 



1.21 Cliaracterislics of the Radar Receiver Input Signal 



In general, the signal radiated by the radar transmitting antenna and 

 received by the receiving antenna consists of intermittent pulses of energy 



SJ ANTENNA BEARING INDICATOR 



PLAN POSITION 

 INDICATOR 



RANGE UNIT 



RANGE INDICATOR 



ANTENNA STEERING WHEEL 



Fig. 2. — SJ Suljinarine Radar. Operating position of radar equipment in conning 

 tower of U. S. Nav\' submarine. 



at microwave frequencies. The methods employed in the generation and 

 propagation of these radar microwave signals have been described else- 

 where.^' ^ For our purpose, it sulBces to state that microwave frequencies 

 extending from 700 me to 10,000 mc are commonly employed. Pulse widths 

 of 0.5 microsecond to 5 microseconds at rey^etition rates extending from 100 

 j)ps to 2000 i)ps are encountered in modern military radar systems, the 



'"The Magnetron as a Generator of Centimeter Waves," J. B. Fisk, H. D. Hagstrum 

 and P. L. Hartman, Bell System Technical Journal, Vol. XXV, April 1946. 



^" Radar Antennas," H. T. Friis and W. D. Lewis, Bell System Techuical Journal, 

 Vol. XXVI, April 1947. 



