Nonlinear low-pass filter

Claim 2

A nonlinear low-pass filter having an input and an output and comprising first and second oppositely poled unipolarly conductive signalling channels commonly responsively coupled to form an input terminal and output coupled to a summing output terminal for alternatively coupling an input signal and a peakdetected, sampled-and-held input signal to the summing output terminal, said filter having substantially no attenuation and no phase shift at frequencies below a selected break frequency corresponding to the reciprocal of a coupling interval of said coupled peak-detected sampled-and-held signal and having substantially zero volts per volt gain at frequencies above said break frequency, each said channel comprising a series-input-coupled diode, said diodes of said channels being mutually oppositely poled; peak-detection means responsively coupled to an input of said channel for peak-detection of an input applied thereto; first sample-and-hold means responsive to said input of said channel and an output of said peak detection means for sampling and holding said unipolar peak-detected input signal; first bipolar switching means normally interconnecting said input of said channel to an output thereof and responsively coupled to an output of said peak detection means for alternatively coupling said output of said channel to an output of said sample-and-hold means for a preselected interval corresponding to the break frequency of said filter.

Claim 3

The device of claim 1 in which there if further provided means for minimizing variations in the frequency response of the filter in the presence of a multiple frequency input.

Claim 4

The device of claim 1 in which there if further provided means for minimizing variations of the frequency response of the filter in response to multiple frequency inputs and comprising second sample-and-hold means responsively connected to said input of said channel; and logic control means for control of said first and second sample-and-hold means for allowing alternative sampling and holding of a subsequent peak detected signal occurring during sampling and holding of an earlier peak-detected signal.

Claim 5

A nonlinear low-pass filter having an input and an output and comprising first and second oppositely poled unipolarly conductive signalling channels commonly responsively coupled to form an input terminal and output coupled to a summing output terminal for alternatively coupling an output signal and a peak-detected, sample-and-held iNput signal to the summing output terminal, said filter having substantially no attenuation and no phase shift at frequencies below a selected break frequency corresponding to the reciprocal of a coupling interval of said coupled peak-detected sampled-and-held signal and having substantially zero volts per volt gain at frequencies above said break frequency, each said channel comprising: a series-input-coupled diode, said diodes of said channels being mutually oppositely poled; means for peak detection responsively coupled to a unipolar input of said channel; sample-and-hold means response to said input of said channel and to an output of said peak detection means for sampling and holding a peak-detected input signal; and bipolar switching means normally interconnecting said input of said channel to an output thereof and responsively coupled to said peak detection means for alternatively coupling said output of said channel to an output of said sample-and-hold means for a preselected interval.

Claim 6

A nonlinear low-pass filter having an input and an output and comprising first and second oppositely poled unipolarly conductive signalling channels commonly responsively coupled to form an input terminal and output coupled to a summing output terminal for alternatively coupling an output signal and a peak-detected, sample-and-held iNput signal to the summing output terminal, said filter having substantially no attenuation and no phase shift at frequencies below a selected break frequency corresponding to the reciprocal of a coupling interval of said coupled peak-detected sampled-and-held signal and having substantially zero volts per volt gain at frequencies above said break frequency, each said channel comprising: a series-input-coupled diode, said diodes of said channels being mutually oppositely poled; means for peak detection responsively coupled to a unipolar input of said channel; sample-and-hold means response to said input of said channel and to an output of said peak detection means for sampling and holding a peak-detected input signal; and bipolar switching means normally interconnecting said input of said channel to an output thereof and responsively coupled to said peak detection means for alternatively coupling said output of said channel to an output of said sample-and-hold means for a preselected interval.

Claim 7

A nonlinear low-pass filter having an input and an output and comprising first and second oppositely poled unipolarly conductive signalling channels commonly responsively coupled to form an input terminal and output coupled to a summing output terminal for alternatively coupling an input signal and a peak-detected, sampled-and-held input signal to the summing output terminal, said filter having substantially no attenuation and no phase shift at frequencies below a selected break frequency corresponding to the reciprocal of a coupling interval of said coupled peak-detected sampled-and-held signal and having substantially zero volts per volt gain at frequencies above said break frequency, and comprising an input differentiator; and an output summing integrator, said first and second oppositely poled unipolarly conductive signalling channels being responsively coupled to an output of said differentiator, an input of said integrator being coupled to said summing output terminal, each of said signalling channels comprising a series-input-coupled diode, said diodes of said channels being mutually oppositely poled; a peak detector responsively coupled to an input of said channel; first sample-and-hold means responsive to said input of said channel and an output of said peak detector for providing sampling and holding a peak-detected input signal; and first bipolar switching means normally interconnecting said input of said channel to an output thereof and responsively coupled to an output of said peak detector for alternatively coupling said output of said channel to an output of said sample-and-hold means for a preselected interval corresponding to the break frequency of said filter.

Claim 8

A nonlinear low-pass filter having an input and an output and comprising first and second oppositely poled unipolarly conductive signalling channels commonly responsively coupled to form an input terminal and output coupled to a summing output terminal for alternatively coupling an input signal and a peak-detected, sampled-and-held input signal to the summing output terminal, said filter having substantially no attenuation and no phase shift at frequencies below a selected break frequency corresponding to the reciprocal of a coupling interval of said coupled peak-detected sampled-and-held signal and having substantially zero volts per volt gain at frequencies above said break frequency, and comprising an input differentiator; and an output summing integrator, said first and second oppositely poled unipolarly conductive signalling channels being responsively coupled to an output of said differentiator, an input of said integrator being coupled to said summing output terminal, each of said signalling channels comprising a series-input-coupled diode, said diodes of said channels being mutually oppositely poled; a peak detector responsively coupled to an input of said channel; first sample-and-hold means responsive to said input of said channel and an output of said peak detector for providing sampling and holding a peak-detected input signal; and first bipolar switching means normally interconnecting said input of said channel to an output thereof and responsively coupled to an output of said peak detector for alternatively coupling said output of said channel to an output of said sample-and-hold means for a preselected interval corresponding to the break frequency of said filter.

Claim 9

The device of claim 5 in which there is further provided means for minimizing variations of the frequency response of the filter in response to multiple frequency inputs and comprising second sample-and-hold means; and logic control means for control of said first and second sample-and-hold means for allowing alternative sampling and holding of a subsequent peak-detected signal occurring during sampling and holding of an earlier peak-detected signal.

Claim 10

The device of claim 6 in which said logic control means comprises second bipolar switching means interposed in circuit for connecting an alternative one of the outputs of said first and second sample-and-hold means to a sample-and-hold input of said first bipolar switching means; and bistable signalling means responsively coupled to said peak detector for providing a two-state control signal, the state of which alternates in response to successive outputs of said peak detection means, a control input of said second bipolar switching means being responsive to said two-state control signal.

Claim 11

A nonlinear low-pass filter having an input and an output and comprising first and second oppositely poled unipolarly conductive signalling channels commonly responsively coupled to fOrm an input terminal and output coupled to a summing output terminal for alternatively coupling an input signal and a peak-detected, sampled-and-held input signal to the summing output terminal, said filter having substantially no attenuation and no phase shift at frequencies below a selected break frequency corresponding to the reciprocal of a coupled interval of said coupled peak-detected sampled-and-held signal and having substantially zero volts per volt gain at frequencies above said break frequency, and comprising an input differentiator; and an output summing integrator, said first and second oppositely poled unipolarly conductive signalling channels being responsively coupled to an output of said differentiator, an input of said integrator being coupled to said summing output terminals, each of said signalling channels comprising a series-input-coupled diode, said diodes of said channels being mutually oppositely poled; a peak detector responsively coupled to said input terminal; first and second sample-and-hold means each having a sampling input coupled to said input terminal and further having a sample control input; a first bipolar relay having a first and second switchable input connected to an output of a mutually exclusive one of said sample-and-hold means, and further having a switch control input and output; a second bipolar relay having a first and second switchable input connected to a respective one of said output of said first relay and said input terminal and further having an output coupled to said output terminal and also having a switch control input; a first and second coincidence gate, each gate having a first input coupled to an output of said peak detector and further having a second input; first and second monostable signalling means, each having an input coupled to an output of a mutually exclusive ones of said first and second coincidence gates; third and fourth coincidence gates, each responsive to mutually exclusive states of said monostable signalling means, said third coincidence gate being responsive to an astable state of said first monostable signalling means and a stable state of said second monostable signalling means; bistable signalling means having a first and second input responsive to an output of mutually exclusive ones of said third and fourth coincidence gates; and a switching control input of said first bipolar relay being responsive to an astable state of each of said monostable signalling means and a switching control input of said second bipolar relay being responsive to a preselected state of said bistable signalling means.

Claim 12

A nonlinear low-pass filter having an input and an output and comprising first and second oppositely poled unipolarly conductive signalling channels commonly responsively coupled to fOrm an input terminal and output coupled to a summing output terminal for alternatively coupling an input signal and a peak-detected, sampled-and-held input signal to the summing output terminal, said filter having substantially no attenuation and no phase shift at frequencies below a selected break frequency corresponding to the reciprocal of a coupled interval of said coupled peak-detected sampled-and-held signal and having substantially zero volts per volt gain at frequencies above said break frequency, and comprising an input differentiator; and an output summing integrator, said first and second oppositely poled unipolarly conductive signalling channels being responsively coupled to an output of said differentiator, an input of said integrator being coupled to said summing output terminals, each of said signalling channels comprising a series-input-coupled diode, said diodes of said channels being mutually oppositely poled; a peak detector responsively coupled to said input terminal; first and second sample-and-hold means each having a sampling input coupled to said input terminal and further having a sample control input; a first bipolar relay having a first and second switchable input connected to an output of a mutually exclusive one of said sample-and-hold means, and further having a switch control input and output; a second bipolar relay having a first and second switchable input connected to a respective one of said output of said first relay and said input terminal and further having an output coupled to said output terminal and also having a switch control input; a first and second coincidence gate, each gate having a first input coupled to an output of said peak detector and further having a second input; first and second monostable signalling means, each having an input coupled to an output of a mutually exclusive ones of said first and second coincidence gates; third and fourth coincidence gates, each responsive to mutually exclusive states of said monostable signalling means, said third coincidence gate being responsive to an astable state of said first monostable signalling means and a stable state of said second monostable signalling means; bistable signalling means having a first and second input responsive to an output of mutually exclusive ones of said third and fourth coincidence gates; and a switching control input of said first bipolar relay being responsive to an astable state of each of said monostable signalling means and a switching control input of said second bipolar relay being responsive to a preselected state of said bistable signalling means.

Claim 13

A nonlinear low-pass filter having an input and an output and comprising first and second oppositely poled unipolarly conductive signalling channels commonly responsively coupled to form an input terminal and output coupled to a summing output terminal for alternatively coupling an input signal and a peak-detected, sampled-and-held input signal to the summing output terminal, said filter having substantially no attenuation and no phase shift at frequencies below a selected break frequency corresponding to the reciprocal of a coupling interval of said coupled peak-detected sampled-and-held signal and having substantially zero volts per volt gain at frequencies above said break frequency, and comprising an input differentiator; and an output summing integrator; said first and second oppositely poled unipolarly conductive signalling channels responsively coupled to an output of said differentiator and output coupled to a respective input of said summing integrator, each of said channels comprising a series-input-coupled diode, said diodes of said channels being mutually oppositely poled; a peak detector responsively coupled to a unipolar input of said channel, and sample-and-hold means responsive to said input of said channel and having a control input responsively coupled to said peak detector for sampling and holdinG a peak-detected input signal, and bipolar switching means normally interconnecting said input of said channel to an output thereof and responsively coupled to said peak detector for alternatively coupling said output of said sample-and-hold means for a preselected interval.

Claim 14

A nonlinear low-pass filter having an input and an output and comprising first and second oppositely poled unipolarly conductive signalling channels commonly responsively coupled to form an input terminal and output coupled to a summing output terminal for alternatively coupling an input signal and a peak-detected, sampled-and-held input signal to the summing output terminal, said filter having substantially no attenuation and no phase shift at frequencies below a selected break frequency corresponding to the reciprocal of a coupling interval of said coupled peak-detected sampled-and-held signal and having substantially zero volts per volt gain at frequencies above said break frequency, and comprising an input differentiator; and an output summing integrator; said first and second oppositely poled unipolarly conductive signalling channels responsively coupled to an output of said differentiator and output coupled to a respective input of said summing integrator, each of said channels comprising a series-input-coupled diode, said diodes of said channels being mutually oppositely poled; a peak detector responsively coupled to a unipolar input of said channel, and sample-and-hold means responsive to said input of said channel and having a control input responsively coupled to said peak detector for sampling and holdinG a peak-detected input signal, and bipolar switching means normally interconnecting said input of said channel to an output thereof and responsively coupled to said peak detector for alternatively coupling said output of said sample-and-hold means for a preselected interval.

Claim 15

A nonlinear low-pass filter having an input and an output and comprising first and second oppositely poled conductive signalling channels commonly responsively coupled to form an input terminal and output coupled to a summing output terminal for alternatively coupling an input signal and a peak-detected, sampled-and-held input signal to the summing output terminal said filter having substantially no attenuation and no phase shift at frequencies below a selected break frequency corresponding to the reciprocal of a coupling interval of said coupled peak-detected sampled-and-held signal and having substantially zero volts per volt gain at frequencies above said break frequency, and comprising an input differentiator; and an output summing integrator; said first and second oppositely poled unipolarly conductive signalling channels being responsively coupled to an output of said differentiator and output coupled to a respective input of said integrator, each of said channels comprising a series-input-coupled diode, said diodes of said channels being mutually oppositely poled; peak-detecting means responsive to a unipolar input of said channel for sampling and holding a peak-detected input signal; and bipolar switching means normally interconnecting said input of said channel to an output thereof, and responsive to the occurrence of a peak-detected input for alternatively coupling said output of said channel to said means for sampling and holding a preselected interval.

Claim 16

A nonlinear low-pass filter having an input and an output and comprising first and second oppositely poled conductive signalling channels commonly responsively coupled to form an input terminal and output coupled to a summing output terminal for alternatively coupling an input signal and a peak-detected, sampled-and-held input signal to the summing output terminal said filter having substantially no attenuation and no phase shift at frequencies below a selected break frequency corresponding to the reciprocal of a coupling interval of said coupled peak-detected sampled-and-held signal and having substantially zero volts per volt gain at frequencies above said break frequency, and comprising an input differentiator; and an output summing integrator; said first and second oppositely poled unipolarly conductive signalling channels being responsively coupled to an output of said differentiator and output coupled to a respective input of said integrator, each of said channels comprising a series-input-coupled diode, said diodes of said channels being mutually oppositely poled; peak-detecting means responsive to a unipolar input of said channel for sampling and holding a peak-detected input signal; and bipolar switching means normally interconnecting said input of said channel to an output thereof, and responsive to the occurrence of a peak-detected input for alternatively coupling said output of said channel to said means for sampling and holding a preselected interval.

Claim 17

A nonlinear low-pass filter having an input and an output and comprising first and second oppositely poled unipolarly conductive signalling channels commonly responsively coupled to form an input terminal and output coupled to a summing output terminal for alternatively coupling an input signal and a peak-detected, sampled-and-held input signal to the summing output terminal, said filter having substantially no attenuation and no phase shift at frequencies below a selected break frequency corresponding to the reciprocal of a coupling interval of said coupled peak-detected sampled-and-held signal and having substantially zero volts per volt gain at frequencies above said break frequency, each said channel comprising a series-input-coupled diode, said diodes of said channels being mutually oppositely poled; peak detection means responsively coupled to a unipolar input of said channel; sample-and-hold means responsively coupled to said unipolar input and further responsive to said peak detection means for providing a unipolar peak-detected sampled-and-held signal; and monostable bipolar switching means normally interconnecting said unipolar input to a responsive input of said summing output terminal and responsively coupled to said peak detection means for alternatively coupling said input of said summing output terminal to an output of said sample and hold means.

Claim 18

A nonlinear low-pass filter having an input and an output and comprising first and second oppositely poled unipolarly conductive signalling channels commonly responsively coupled to form an input terminal and output coupled to a summing output terminal for alternatively coupling an input signal and a peak-detected, sampled-and-held input signal to the summing output terminal, said filter having substantially no attenuation and no phase shift at frequencies below a selected break frequency corresponding to the reciprocal of a coupling interval of said coupled peak-detected sampled-and-held signal and having substantially zero volts per volt gain at frequencies above said break frequency, each said channel comprising a series-input-coupled diode, said diodes of said channels being mutually oppositely poled; peak detection means responsively coupled to a unipolar input of said channel; sample-and-hold means responsively coupled to said unipolar input and further responsive to said peak detection means for providing a unipolar peak-detected sampled-and-held signal; and monostable bipolar switching means normally interconnecting said unipolar input to a responsive input of said summing output terminal and responsively coupled to said peak detection means for alternatively coupling said input of said summing output terminal to an output of said sample and hold means.

Claim 19

The device of claim 11 in which there is further provided: output signal-smoothing means responsively coupled to said summing output terminal; and compensatory signal-shaping means interposed at input of said filter and having a describing function corresponding to the reciprocal of the describing function of said output signal-smoothing means.