Unipolar acoustic pulse generator apparatus

Claim 2

Apparatus for producing a unipolar displacement of the radiating face of an electroacoustic transducer having opposite radiating and non-radiating faces, said unipolar displacement being characterized by a duration time parameter 2to, characterized in that to is substantially equal to an integer multiple of the time required for an acoustic wave to travel from one face of said transducer to the other, means for generating a partly discontinuous signal waveform and means for applying said signal waveform to said transducer.

Claim 3

Apparatus for producing a unipolar displacement of the radiating face of an electroacoustic transducer having opposite radiating and non-radiating faces, said unipolar displacement being characterized by a duration time parameter 2to, characterized in that to is substantially equal to an integer multiple of the time required for an acoustic wave to travel from one face of said transducer to the other, means for generating a partly discontinuous signal waveform and means for applying said signal waveform to said transducer.

Claim 4

Apparatus for producing a unipolar displacement of the radiating face of an electroacoustic transducer having opposite radiating and non-radiating faces, said unipolar displacement being characterized by a duration time parameter 2to, characterized in that to is substantially equal to an integer multiple of the time required for an acoustic wave to travel from one face of said transducer to the other, means for generating a partly discontinuous signal waveform and means for applying said signal waveform to said transducer.

Claim 5

The apparatus defined in claim 1 wherein said means for generating comprises: means for generating a trigger signal; a plurality of shaped pulse generating channels responsive to said trigger signal, each of said channels comprising means for delaying said trigger signal, means responsive to the delayed trigger signal for generating a rectangular pulse of predetermined amplitude and duration, and means for shaping said rectangular pulse to produce a shaped output pulse; and means for summing the shaped output pulses of each of said channels to produce said partly discontinuous signal waveform.

Claim 6

The apparatus defined in claim 1 wherein said means for generating comprises: means for generating a trigger signal; a plurality of shaped pulse generating channels responsive to said trigger signal each of said channels comprising Means for delaying said trigger signal, means responsive to the delayed trigger signal for generating a rectangular pulse of predetermined amplitude and duration, and means for shaping said rectangular pulse to produce a shaped output pulse; means for summing the shaped output pulses of each of said channels; and means for low pass filtering the sum of the shaped output pulses to produce said partly discontinuous signal waveform.

Claim 7

The apparatus defined in claim 1 wherein to is substantially equal to the time required for an acoustic wave to travel from one face of said transducer to the other.

Claim 8

The apparatus defined in claim 4 wherein said partly discontinuous signal waveform is characterized by an initial signal discontinuity followed by a first pulse segment of decreasing signal amplitude, a second pulse segment of increasing signal amplitude, and a final signal discontinuity.

Claim 9

Apparatus for generating unipolar acoustic pulses in an acoustic medium comprising: a transducer having a radiating face and an opposite non-radiating face and means for applying a signal to said transducer for causing the radiating face of the transducer to displace from a rest position to maximum displacement during a first interval of time to and to return from maximum displacement to said rest position during a second subsequent interval of time to, wherein to is substantially equal to an integer multiple of the time required for an acoustic wave to propagate from one face of the transducer to the other.

Claim 10

Apparatus for generating unipolar acoustic pulses in an acoustic medium comprising: a transducer having a radiating face and an opposite non-radiating face and means for applying a signal to said transducer for causing the radiating face of the transducer to displace from a rest position to maximum displacement during a first interval of time to and to return from maximum displacement to said rest position during a second subsequent interval of time to, wherein to is substantially equal to an integer multiple of the time required for an acoustic wave to propagate from one face of the transducer to the other.

Claim 11

The apparatus defined in claim 6 wherein said means for applying comprises: means for generating a trigger signal; a plurality of shaped pulse generating channels responsive to said trigger signal, each of said channels comprising means for delaying said trigger signal, means responsive to the delayed trigger signal for generating a rectangular pulse of predetermined amplitude and duration, and means for shaping said rectangular pulse to produce a shaped output pulse; and means for summing the shaped output pulses of each of said channels to produce the signal applied to said transducer.

Claim 12

The apparatus defined in claim 6 wherein said means for applying comprises: means for generating a trigger signal; a plurality of shaped pulse generating channels responsive to said trigger signal, each of said channels comprising means for delaying said trigger signal, means responsive to the delayed trigger signal for generating a rectangular pulse of predetermined amplitude and duration, and means for shaping said rectangular pulse to produce a shaped output pulse; means for summing the shaped output pulse of each of said channels; and means for low pass filtering the sum of the shaped output pulses to produce the signal applied to said transducer.

Claim 13

Apparatus for generating unipolar acoustic pulses in an acoustic medium comprising: a transducer having a radiating face and an opposite non-radiating face and means for applying a signal to said transducer to cause the radiating face of the transducer to displace from a rest position to maximum displacement during a first interval of time to and to return from maximum displacement to said rest position during a second subsequent interval of time to, wherein to is substantially equal to the time required for an acoustic wave to propagate through the transducer from one face to the other.

Claim 14

Apparatus for generating unipolar acoustic pulses in an acoustic medium comprising: a transducer having a radiating face and an opposite non-radiating face and means for applying a signal to said transducer to cause the radiating face of the transducer to displace from a rest position to maximum displacement during a first interval of time to and to return from maximum displacement to said rest position during a second subsequent interval of time to, wherein to is substantially equal to the time required for an acoustic wave to propagate through the transducer from one face to the other.

Claim 15

The apparatus defined in claim 9 wherein said means for applying comprises: means for generating a signal discontinuity of a first polarity at the start of said first interval of time to and means for generating a signal discontinuity of a polarity opposite said first polarity at the end of said second interval of time to.

Claim 16

The apparatus defined in claim 9 wherein said means for applying comprises means for generating a unipolar signal pulse having a leading edge timed to coIncide with the start of said first interval of time to and a trailing edge timed to coincide with the end of said second interval of time to.

Claim 17

Apparatus for producing a unipolar displacement of the radiating face of an electroacoustic transducer, said transducer having an acoustic velocity c and a longitudinal dimension L perpendicular to its radiating face and said unipolar displacement being characterized by a duration time parameter 2to, characterized in that to is substantially equal to an integer multiple of the quotient (L/c,) means for generating a partly discontinuous signal waveform, and means for applying said signal waveform to said transducer.

Claim 18

Apparatus for producing a unipolar displacement of the radiating face of an electroacoustic transducer, said transducer having an acoustic velocity c and a longitudinal dimension L perpendicular to its radiating face and said unipolar displacement being characterized by a duration time parameter 2to, characterized in that to is substantially equal to an integer multiple of the quotient (L/c,) means for generating a partly discontinuous signal waveform, and means for applying said signal waveform to said transducer.

Claim 19

The apparatus defined in claim 12 wherein said means for generating comprises: means for generating a trigger signal; a plurality of shaped pulse generating channels responsive to said trigger signal, each of said channels comprising means for delaying said trigger signal, means responsive to the delayed trigger signal for generating a rectangular pulse of predetermined amplitude and duration, and means for shaping said rectangular pulse to produce a shaped output pulse; and means for summing the shaped output pulses of each of said channels to produce said partly discontinuous signal waveform.

Claim 20

The apparatus defined in claim 12 wherein said means for generating comprises: means for generating a trigger signal; a plurality of shaped pulse generating channels responsive to said trigger signal, each of said channels comprising means for delaying said trigger signal, means responsive to the delayed trigger signal for generating a rectangular pulse of predetermined amplitude and duration, and means for shaping said rectangular pulse to produce a shaped output pulse; means for summing the shaped output pulses of each of said channels; and means for low pass filtering the sum of the shaped output pulses to produce said partly discontinuous signal waveform.

Claim 21

The apparatus defined in claim 12 wherein to is substantially equal to the quotient L/c.

Claim 22

The apparatus defined in claim 15 wherein said partly discontinuous signal waveform is characterized by an initial signal discontinuity followed by a first pulse segment of decreasing signal amplitude, a second pulse segment of increasing signal amplitude, and a final signal discontinuity.

Claim 23

Apparatus for generating unipolar acoustic pulses in an acoustic medium comprising: a transducer having a radiating face and a longitudinal dimension L perpendicular to said radiating face, the material of said transducer having an acoustic velocity c and means for applying a signal to said transducer for causing the radiating face of said transducer to displace from a rest position to maximum displacement during a first interval of time to and to return from maximum displacement to said rest position during a second subsequent interval of time to, wherein to is substantially equal to an integer multiple of the quotient L/c.

Claim 24

Apparatus for generating unipolar acoustic pulses in an acoustic medium comprising: a transducer having a radiating face and a longitudinal dimension L perpendicular to said radiating face, the material of said transducer having an acoustic velocity c and means for applying a signal to said transducer for causing the radiating face of said transducer to displace from a rest position to maximum displacement during a first interval of time to and to return from maximum displacement to said rest position during a second subsequent interval of time to, wherein to is substantially equal to an integer multiple of the quotient L/c.

Claim 25

The apparatus defined in claim 17 wherein to is substantially equal to the quotient L/c.

Claim 26

The apparatus defined in claim 17 wherein said means for applying comprises: means for generating a trigger signal; a plurality of shaped pulse generating channels responsive to said trigger signal, each of said channels comprising means for delaying said trigger signal, means responsive to the delayed trigger signal for generating a rectangular pulse of predetermined amplitude and duration, and means for shaping said rectangular pulse to produce a shaped output pulse; and means for summing the shaped output pulses of each of said channels to produce the signal applied to said transducer.