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BlLLl. SYSTEM TECHNICAL JOURNAL 



tional to the amplitude of the field of the radiation at a great distance 

 from the array in the direction of the radius vector is required. Two 

 particular cases will be illustrated in order to give some idea of the 

 surface which shows the group effect of the array; for actual antennae, 

 the radius vector of this surface must be multiplied by the corre- 

 sponding radius vector of the space characteristic of the individual 

 antenna in order to obtain the actual characteristic of the array. 



n = 2 

 n=3 

 n=4 



n = oo 



Fig. 10 — Comparison of finilc and infinite arrays within a total distance ot one 

 wave-length, and within a total phase interval of one period 



