Electronic altitude encoder

Claim 2

An altitude measuring device comprising pressure transducer means for providing an output signal which is a function of the barometric pressure at the altitude sought to be measured; integrator means for providing a waveform which represents a curve of altitude as a function of barometric pressure, and comparator means having one input coupled to the output of said pressure transducer means and a second input coupled to said integrator means, said comparator means being operative to provide a transition of its input when the output signal provided by said pressure transducer means intersects the waveform provided by said integrator means, whereby the point of time of the transition of the output is a function of the altitude sought to be measured.

Claim 3

The device as described in claim 1 and further including storage means coupled to the output of said comparator means for providing a digitally encoded information of the altitude sought to be measured.

Claim 4

Encoding means for providing a digitally encoded information of a measured function which varies approximately exponentially comprising transducer means for providing an output signal which varies linearly with respect to said measured function; integrator means for providing an exponential waveform which varies approximately in accordance with the variation of said function, and means coupled to the outputs of said transducer means and said integrator means for combining said output signal from said transducer means and said exponential waveform from said integrator means for providing a digitally encoded information at the point of intersection of said output signal with said exponential waveform to provide a digitally encoded measurement of said function.

Claim 5

Encoding means for providing a digitally encoded information of a measured function which varies approximately exponentially comprising transducer means for providing an output signal which varies linearly with respect to said measured function; integrator means for providing an exponential waveform which varies approximately in accordance with the variation of said function, and means coupled to the outputs of said transducer means and said integrator means for combining said output signal from said transducer means and said exponential waveform from said integrator means for providing a digitally encoded information at the point of intersection of said output signal with said exponential waveform to provide a digitally encoded measurement of said function.

Claim 6

An altitude measuring device comprising pressure transducer means for providing an output signal which is a function of the barometric pressure at the altitude sought to be measured; integrator means for providing a waveform which represents a curve of altitude as a function of barometric pressure; and means coupled to the outputs of said pressure transducer means and said integrator means for combining said output signal from said pressure transducer means and said integrator means.

Claim 7

An altitude measuring device comprising pressure transducer means for providing an output signal which is a function of the barometric pressure at the altitude sought to be measured; integrator means for providing a waveform which represents a curve of altitude as a function of barometric pressure; and means coupled to the outputs of said pressure transducer means and said integrator means for combining said output signal from said pressure transducer means and said integrator means.

Claim 8

An integrator responsive to an input waveform at an input terminal for providing an output waveform at an output terminal which output waveform represents a curve of altitude as a function of barometric pressure for use in measuring altitude comprising a passive integrator network having a first resistor-capacitor circuit for providing a first exponential waveform, and an active integrator network having a feedback network which includes a second resistor-capacitor network for providing a second exponential waveform whereby the combination of said first exponential waveform with said second exponential waveform closely approximates a curve of altitude as a function of barometric pressure.

Claim 9

An integrator responsive to an input waveform at an input terminal for providing an output waveform at an output terminal which output waveform represents a curve of altitude as a function of barometric pressure for use in measuring altitude comprising a passive integrator network having a first resistor-capacitor circuit for providing a first exponential waveform, and an active integrator network having a feedback network which includes a second resistor-capacitor network for providing a second exponential waveform whereby the combination of said first exponential waveform with said second exponential waveform closely approximates a curve of altitude as a function of barometric pressure.

Claim 10

The devices described in claim 5 and wherein said active integrator network further includes an operational amplifier having a summing terminal and said passive integrator network and said feedback network are coupled to said summing terminal.

Claim 11

The device as described in claim 6 and wherein said first resistor-capacitor network has an input coupled to said input terminal of said integrator and an output terminal and further including: a first resistor coupled between said output of said first resistor-capacitor network and said summing terminal of said operational amplifier, and a second resistor coupled between said input terminal of said integrator and said summing terminal of said operational amplifier.

Claim 12

The device as described in claim 5 and wherein said second resistor-capacitor network in said feedback network includes a resistor and a capacitor coupled in parallel.

Claim 13

An altitude measuring device comprising pressure transducer means for providing an output signal which is a function of the barometric pressure at the altitude sought to be measured, integrator means for providing a waveform which represents a curve of altitude as a function of barometric pressure, comparator means having one input coupled to the output of said pressure transducer means and a second input coupled to said integrator means, said comparator means being operative to provide a transition of its input when the output signal provided by said pressure transducer means intersect the waveform provided by said integrator means, whereby the point of time of the transition of the output is a function of the altitude sought to be measured, counter means for providing a series of regularly recurring pulses, code converter means coupled to the output of said counter means for providing an encoded count of the number of pulses produced by said counter means, and storage means having one input coupled to the output of said comparator means and a second input coupled to the output of said code converter means, said storage means being operative to temporarily store a digitally encoded representation of the altitude sought to be measured by temporarily storing the encoded output of said code converter at the point of time when said comparator provides a change of state of its output.

Claim 14

An altitude measuring device comprising pressure transducer means for providing an output signal which is a function of the barometric pressure at the altitude sought to be measured, integrator means for providing a waveform which represents a curve of altitude as a function of barometric pressure, comparator means having one input coupled to the output of said pressure transducer means and a second input coupled to said integrator means, said comparator means being operative to provide a transition of its input when the output signal provided by said pressure transducer means intersect the waveform provided by said integrator means, whereby the point of time of the transition of the output is a function of the altitude sought to be measured, counter means for providing a series of regularly recurring pulses, code converter means coupled to the output of said counter means for providing an encoded count of the number of pulses produced by said counter means, and storage means having one input coupled to the output of said comparator means and a second input coupled to the output of said code converter means, said storage means being operative to temporarily store a digitally encoded representation of the altitude sought to be measured by temporarily storing the encoded output of said code converter at the point of time when said comparator provides a change of state of its output.

Claim 15

The device as described in claim 9 further including: clock means coupled to said counter for providing pulses, and synchronizer means coupled between sad comparator means and said storage means and having an input coupled to the output of said clock means, said synchronizer means including delay means for synchronizing the operation of said comparator with the operation of said counter means, said code converter means and said storage means.

Claim 16

Encoding means for providing a digitally encoded information of a measured function which varies approximately exponentially comprising transducer means for providing an output signal which varies linearly with respect to said measured function, integrator means for providing an exponential waveform which varies approximately in accordance with the variation of said function, means coupled to the outputs of said transducer means and said integrator means for combining said output signal from said transducer means and said exponential waveform from said integrator means for providing a digitally encoded information at the point of intersection of said output signal with said exponential waveform to provide a digitally encoded measurement of said function said means coupled to the output of said transducer means and said integrator means includes storage means having a plurality of flip-flops for providing said digitally encoded information at the point of intersection of said output signal with said exponential waveform.

Claim 17

Encoding means for providing a digitally encoded information of a measured function which varies approximately exponentially comprising transducer means for providing an output signal which varies linearly with respect to said measured function, integrator means for providing an exponential waveform which varies approximately in accordance with the variation of said function, means coupled to the outputs of said transducer means and said integrator means for combining said output signal from said transducer means and said exponential waveform from said integrator means for providing a digitally encoded information at the point of intersection of said output signal with said exponential waveform to provide a digitally encoded measurement of said function said means coupled to the output of said transducer means and said integrator means includes storage means having a plurality of flip-flops for providing said digitally encoded information at the point of intersection of said output signal with said exponential waveform.

Claim 18

Encoding means for providing a digitally encoded information of a measured function which varies approximately exponentially comprising transducer means for providing an output signal which varies linearly with respect to said measured function, integrator means for providing an exponential waveform which varies approximately in accordance with the variation of said function, means coupled to the outputs of said transducer means and said integrator means for combining said output signal from said transducer means and said exponential waveform from said integrator means for providing a digitally encoded information at the point of intersection of said output signal with said exponential waveform to provide a digitally encoded measurement of said function, counter means for providing a series of regularly recurring pulses, code converter means coupled to the output of said counter means for providing an encoded count of the number of pulses produced by said clock means, and storage means coupled to the output of said code converter means having a plurality of flip-flops for providing said digitally encoded information at the point of intersection of said output signal with said exponential waveform.

Claim 19

Encoding means for providing a digitally encoded information of a measured function which varies approximately exponentially comprising transducer means for providing an output signal which varies linearly with respect to said measured function, integrator means for providing an exponential waveform which varies approximately in accordance with the variation of said function, means coupled to the outputs of said transducer means and said integrator means for combining said output signal from said transducer means and said exponential waveform from said integrator means for providing a digitally encoded information at the point of intersection of said output signal with said exponential waveform to provide a digitally encoded measurement of said function, counter means for providing a series of regularly recurring pulses, code converter means coupled to the output of said counter means for providing an encoded count of the number of pulses produced by said clock means, and storage means coupled to the output of said code converter means having a plurality of flip-flops for providing said digitally encoded information at the point of intersection of said output signal with said exponential waveform.

Claim 20

An altitude measuring device comprising pressure transducer means for providing an output signal which is a function of the barometric pressure at the altitude sought to be measured, integrator means for providing a waveform which represents a curve of altitude as a function of barometric pressure, means coupled to the outputs of said pressure transducer means and said integrator means for combining said output signal from said pressure transducer means and said integrator means, a passive integrator network, and an active integrator network coupled to the output of said passive integrator network.

Claim 21

An altitude measuring device comprising pressure transducer means for providing an output signal which is a function of the barometric pressure at the altitude sought to be measured, integrator means for providing a waveform which represents a curve of altitude as a function of barometric pressure, means coupled to the outputs of said pressure transducer means and said integrator means for combining said output signal from said pressure transducer means and said integrator means, a passive integrator network, and an active integrator network coupled to the output of said passive integrator network.

Claim 22

A device as described in claim 13 wherein said first passive integrator network includes a resistor-capacitor network.

Claim 23

The device as described in claim 13 wherein said second active integrator network includes an operational amplifier having a feedback circuit, said feedback circuit including a resistor-capacitor network.