OMNIDIRECTIONAL ULTRASONIC COMMUNICATION SYSTEM

摘要

An ultrasonic communication system includes an omnidirectional ultrasonic transducer (30) including a housing (34) having a closed side (36) and an open side (38) defining an aperture (40) in the housing (34). A diaphragm (42) is mounted into the housing (34) to form a sealed cavity (44) between the diaphragm (42) and the closed side (36) of the housing (34). A second side of the diaphragm (42) is free to transmit ultrasonic signals through the aperture (40). The diaphragm (42) and aperture (40) both have a largest dimension that is less than or equal to one-quarter wavelength of an ultrasonic signal to be transmitted by the transducer (30), such that the transducer (30) behaves as a monopole and radiates substantially omnidirectionally.