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BELL SYSTEM TECHNICAL JOURNAL 



Standing Wave Patterns 

 This standing wave pattern has not yet been sufficiently studied. 

 It is easy, by driving the receiver car sufficiently slowly, to show that 

 some of the "fringes" are due to reradiation from individual trees along 

 the roadside. Vertical metallic guy wires and other metallic structures 

 are equally good reradiators. The type of interference pattern which 

 would be expected from a reradiating tree is shown in Fig. 3, and this is 



TO TRANSMITTER 



Fig. 3 — Standing wave system surrounding a tree. Phase shift on reflection 180 

 degrees. Curves show first five lines of minimum field. 



substantially what was found by driving the receiver car around iso- 

 lated trees. But in general the pattern is not as simple as this and, 

 what is of more importance, the maximum/minimum ratio may run as 

 high as fifty to one. A road bordered with trees gives a very rough 

 pattern. 



An. open field of some 20 acres extent was available about a mile 

 (1.6 kilometers) from the transmitter. This field lay on a "bench" 

 about 90 feet (27.5 meters) above the Holmdel laboratory ground 



