BAT'S ORIGINAL PULSE 

 P 



END WALL ECHO 



E 



WIRE ECHO 

 W 



m — 



fi^^tA^l^^^ 



Fig. 14. Schematic graphs of a bat's chirp and the 

 echoes in the flight room {Fig. 12) under various test 

 conditions: A— approaching 0.46-millimeter wires in the 

 middle of room; B— approaching same wires near the 

 end wall; C— approaching larger wires close to the end 

 wall {note the larger echo); and D— approaching an 

 insect under natural conditions in woods where many 

 other objects also return echoes. {For simplicity the 

 frequency modulation is not shown.) 



102 



