Table 2.

Maximum and minimum of dB values obtained from the directivity measurements for the Fibonacci spiral-like transducer.

	Transmission				Reception
	Horizontal Plane		Vertical Plane		Horizontal Plane		Vertical Plane
Frequency (kHz)	Max (dB)	Min (dB)	Max (dB)	Min (dB)	Max (dB)	Min (dB)	Max (dB)	Min (dB)
20	86	68	84	58	−87	−109	−92	−105
40	79	68	75	59	−102	−118	−105	−118
60	78	64	79	62	−103	−114	−102	−114
80	69	60	67	52	−109	−119	−110	−119