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BELL SYSTEM TECHNICAL JOURNAL 



A family of calculated directional patterns of the experimental 

 MUSA is shown in Figs. 19 and 20. At the top of each column is shown 

 the principal lobe of the vertical directional pattern of the unit rhombic 

 antenna, calculated in the median plane. Beneath are shown six 

 vertical patterns of the MUSA, which are obtained by multiplying the 



RHOMBUS PATTERNS 



MUSA PATTERNS (-0 = 1) 



0.5 





 1.0 



0.5 



Z 

 y 1.0 



0.5 



5 



H 1.0 



0.5 







1.0 



0.5 



5 to 15 20 25 30 35 5 10 15 20 25 30 35 

 EARTH ANGLE 6, IN DEGREES 



Fig. 19 — Vertical directional patterns of the experimental MUSA. 



array factor ^^ by the unit antenna pattern. The upper pattern 

 corresponds to phasing for zero angle. The remaining ones are plotted 

 for increments of 60 degrees of phase. 



These patterns fall short of the "ideal," which the reader may have 

 visualized while reading Section II, in two ways. First, the unit an- 



^^ Calculated from (3) putting u = 1. 



