Amplitude regulator means for separating frequency variations and amplitude variations of electrical signals

Claim 2

An amplitude regulator circuit in combination with communication systems and/or with devices reconising and/or recording image signals, speech signals, musical signals; said amplitude regulator circuit comprising an amplifier having an input and an output, the gain of which can be varied by a feedback loop chain in circuit with the amplifier embodying a loop amplifier, a rectifier and a low-pass filter, a steep lowpass filter means located in front of the input of said amplifier, in order to extract the fundamental frequency of said signals, wheresas the amplitude of the fundamental frequency of said signals is recovered by said circuit, a band-pass filter located at the input of said feedback loop chain in order to further select the fundamental frequency, the boundary frequency of said low-pass filter having a value chosen in a range between about 100 and 150 Hz with a damping between 18 and 30 dB/octave, said amplitude regulator circuit feeding two electrical signal circuits in parallel, one circuit including means for counting a zero-crossing of waves of the fundamental frequency, the other circuit embodying a band-pass filter and electronic switches which interrupt the pulses of the counting means going to a display in case of voiceless sounds.

Claim 3

An amplitude regulator circuit in combination with communication systems and/or with devices recognising and/or recording image signals, speech signals, musical signals; said amplitude regulator circuit comprising an amplifier having an input and an output, the gain of which can be varied by a feedback loop chain in circuit with the amplifier embodying a loop amplifier, a rectifier and a low-pass filter, a steep low-pass filter means located in front of the input of said amplifier, in order to extract the fundamental frequency of said signals, whereas the amplitude of the fundamental frequency of said signals is recovered by said circuit, a band-pass filter located at the input of said feedback loop chain in order to further select the fundamental frequency, the boundary frequency of said low-pass filter having a value chosen in a range between about 100 and 150 Hz with a damping between 18 and 30 dB/octave, at least an additional amplifier for higher frequencies connected parallel to the amplifier for the fundamental frequency, the output signal of said additional amplifier being fed to logic means through a band-pass filter and smoothing filter, and said logic means recognising the sound or the phoneme according to the time difference between the signals coming from the lowerand from the higher frequency components. lower and

Claim 4

An amplitude regulator circuit in combination with communication systems and/or with devices recognising and/or recording image signals, speech signals, musical signals; said amplitude regulator circuit comprising an amplifier having an input and an output, the gain of which can be varied by a feedback loop chain in circuit with the amplifier embodying a loop amplifier, a rectifier and a low-pass filter, a steep low-pass filter means located in front of the input of said amplifier, in order to extract the fundamental frequency of said signals, whereas the amplitude of the fundamental frequency of said signals is recovered by said circuit, a band-pass filter located at the input of said feedback loop chain in order to further select the fundamental frequency, the boundary frequency of said low-pass filter having a value chosen in a range between about 100 and 150 Hz with a damping between 18 and 30 dB/octave, at least an additional amplifier for higher frequencies connected parallel to the amplifier for the fundamental frequency, the output signal of said additional amplifier being fed to logic means through a band-pass filter and smoothing filter, and said logic means recognising the sound or the phoneme according to the time difference between the signals coming from the lowerand from the higher frequency components. lower and

Claim 5

An amplitude regulator circuit as defined in claim 2, wherein the loop signal arriving at the input of said amplifier goes through a line to said logic means for displaying the dynamics (level-variations) of the input signal.

Claim 6

An amplitude regulator circuit in combination with communication systems and/or with devices recognising and/or recording image signals, speech signals, musical signals; said amplitude regulator circuit comprising an amplifier having an input and an output, the gain of which can be varied by a feedback loop chain in circuit with the amplifier embodying a loop amplifier, a rectifier and a low-pass filter, a steep low-pass filter means located in front of the input of said amplifier, in order to extract the fundamental frequency of said signals, whereas the amplitude of the fundamental frequency of said signals is recovered by said circuit, a bandpass filter located at the input of said feedback loop chain in order to further select the fundamental frequency, the boundary frequency of said low-pass filter having a value chosen in a range between about 100 and 150 Hz with a damping between 18 and 30 dB/octave, an amplifier for the fundamental frequency and at least a further amplifier for higher frequencies connected In parallel at the input, the output signal of said fundamental frequency amplifier being received by a counter means counting the zero-crossing points of waves of the fundamental frequency, the further output signal being delivered to filter means of the specific frequency components and through smoothing filter means to separate inputs of said logic means, the connections in the logic means being adapted to change the higher frequency components of the signals relating to the variations of the fundamental frequency.

Claim 7

An amplitude regulator circuit in combination with communication systems and/or with devices recognising and/or recording image signals, speech signals, musical signals; said amplitude regulator circuit comprising an amplifier having an input and an output, the gain of which can be varied by a feedback loop chain in circuit with the amplifier embodying a loop amplifier, a rectifier and a low-pass filter, a steep low-pass filter means located in front of the input of said amplifier, in order to extract the fundamental frequency of said signals, whereas the amplitude of the fundamental frequency of said signals is recovered by said circuit, a bandpass filter located at the input of said feedback loop chain in order to further select the fundamental frequency, the boundary frequency of said low-pass filter having a value chosen in a range between about 100 and 150 Hz with a damping between 18 and 30 dB/octave, an amplifier for the fundamental frequency and at least a further amplifier for higher frequencies connected In parallel at the input, the output signal of said fundamental frequency amplifier being received by a counter means counting the zero-crossing points of waves of the fundamental frequency, the further output signal being delivered to filter means of the specific frequency components and through smoothing filter means to separate inputs of said logic means, the connections in the logic means being adapted to change the higher frequency components of the signals relating to the variations of the fundamental frequency.

Claim 8

An amplitude regulator in combination with communication systems and/or with devices recognising and/or recording image signals, speech signals, musical signals; said amplitude regulator comprising an amplifier having an input, the gain of which can be varied by a feedback loop chain in circuit with said amplifier embodying a loop amplifier, a rectifier and a low-pass filter, said low-pass filter including a capacitor, further comprising an additional rectifier and a resistance connected between said low-pass filter and the input of said amplifier, said additional rectifier and resistance controlling a time-constant which depends upon the direction of current flow, in order to regulate the ascending slope of the loop signal independently from its descending slope and to discriminate initial and end transitions of said loop signal.

Claim 9

An amplitude regulator in combination with communication systems and/or with devices recognising and/or recording image signals, speech signals, musical signals; said amplitude regulator comprising an amplifier having an input, the gain of which can be varied by a feedback loop chain in circuit with said amplifier embodying a loop amplifier, a rectifier and a low-pass filter, said low-pass filter including a capacitor, further comprising an additional rectifier and a resistance connected between said low-pass filter and the input of said amplifier, said additional rectifier and resistance controlling a time-constant which depends upon the direction of current flow, in order to regulate the ascending slope of the loop signal independently from its descending slope and to discriminate initial and end transitions of said loop signal.

Claim 10

An amplitude regulator as defined in claim 4, further comprising a parallel connection between the input of a fundamental frequency amplifier and the input of at least a further amplifier of the higher frequency components, a filter provided in each connection of these higher frequency components, the boundaries of which are modified by a resistor, variable in response to fundamental frequency signals.

Claim 11

An amplitude regulator in combination with communication systems and/or with devices recognizing and/or recording image signals, speech signals, musical signals; said amplitude regulator comprising a first amplifier, the gain of which can be varied in reverse direction by a feedback loop chain in circuit with the first amplifier embodying a loop amplifier, a rectifier and a low-pass filter, a second amplifier, the input of said first amplifier being coupled with the input of said second amplifier, a feed forward loop chain in circuit with the second amplifier for varying the gain of said second amplifier in forward direction, said feed forward loop chain for said second amplifier comprising a loop amplifier, rectifier and a low-pass filter, the output signal of said first amplifier providing the input signal of said feed forward loop chain.

Claim 12

An amplitude regulator in combination with communication systems and/or with devices recognizing and/or recording image signals, speech signals, musical signals; said amplitude regulator comprising a first amplifier, the gain of which can be varied in reverse direction by a feedback loop chain in circuit with the first amplifier embodying a loop amplifier, a rectifier and a low-pass filter, a second amplifier, the input of said first amplifier being coupled with the input of said second amplifier, a feed forward loop chain in circuit with the second amplifier for varying the gain of said second amplifier in forward direction, said feed forward loop chain for said second amplifier comprising a loop amplifier, rectifier and a low-pass filter, the output signal of said first amplifier providing the input signal of said feed forward loop chain.

Claim 13

An amplitude regulator as defined in claim 7, wherein both loop amplifiers of the reverse and forward loops have similar gains so that the average value of the output level becomes nearly a linear function of the input level.

Claim 14

An amplitude regulator in combination with communication systems and/or with devices recognizing and/or recording image signals, speech signals, musical signals; said amplitude regulator comprising a first amplifier having an input, the gain of which can be varied in reverse direction by a feedback loop chain in circuit with the first amplifier embodying a loop amplifier, a rectifier and a low-pass filter, a second amplifier having an input, the input of said first amplifier being coupled with the input of said second amplifier, a forward loop chain in circuit with the second amplifier for varying the gain of said second amplifier in forward direction, the output signal of said first amplifier providing the input signal of said forward loop chain.

Claim 15

An amplitude regulator in combination with communication systems and/or with devices recognizing and/or recording image signals, speech signals, musical signals; said amplitude regulator comprising a first amplifier having an input, the gain of which can be varied in reverse direction by a feedback loop chain in circuit with the first amplifier embodying a loop amplifier, a rectifier and a low-pass filter, a second amplifier having an input, the input of said first amplifier being coupled with the input of said second amplifier, a forward loop chain in circuit with the second amplifier for varying the gain of said second amplifier in forward direction, the output signal of said first amplifier providing the input signal of said forward loop chain.