Altimeter setting indicator system and method of obtaining said setting

Claim 3

The system of claim 1 further including display means responsive to said altimeter setting pressure signal for displaying said altimeter setting pressure.

Claim 4

The system of claim 1 in which said barometric pressure sensor signal has a predetermined characteristic with respect to pressure altitude and said first converter means comprises first variable gain means responsive to said sensor signal, altitude indicating means responsive to the output signal of said first variable gain means, and first feedback means responsive to the output signal of said altitude indicating means and including first predetermined program means relating said sensor signal characteristic to pressure altitude under standard day conditions, said first variable gain means being responsive to the output signal of said first feedback means for controlling the gain thereof for rendering said output signal of said altitude indicating means proportional to local pressure altitude under standard day conditions.

Claim 5

The system of claim 3 in which said barometric pressure sensor means comprises vibratory pressure sensor means for providing groups of pulses of pulse count in accordance with said local barometric pressure, said first program means includes means relating said sensor pulse count to pressure altitude under standard day conditions, said first variable gain means comprises first variable frequency altering means for altering said pulse count in accordance with said output signal of said first feedback means, and said altitude indicating means comprises altitude pulse counting means for providing an altitude pulse count signal in accordance with the altered pulse count from said first frequency altering means, whereby said altitude pulse count signal of said altitude pulse counting means is rendered proportional to local pressure altitude under standard day conditions.

Claim 6

The system of claim 4 in which said vibrating pressure sensor means comprises a vibratory pressure sensor for providing a cyclic signal with frequency a function of barometric pressure, a sensor counter responsive to said cyclic signal for providing a gating pulse of width in accordance with a predetermined number of cycles thereof, a source of clock pulses, and gating means responsive to said clock pulses and to said gating pulse for transmitting said clock pulses during the occurrence of said gating pulse thereby providing said groups Of pulses.

Claim 7

The system of claim 4 in which said first variable frequency altering means comprises a binary rate multiplier having one input responsive to said groups of pulses, another input responsive to said output signal of said first feedback means and its output coupled to said altitude pulse counting means.

Claim 8

The system of claim 4 in which said first feedback means comprises a first memory address counter coupled to said altitude pulse counting means for providing a sequence of digital address signals in response to said altitude pulse count signal, and first memory means coupled to said first memory address counter for providing predetermined digital parameter signals in response to said address signals for controlling said first variable frequency altering means.

Claim 9

The system of claim 4 in which said computer means comprises comparator means responsive to said altitude pulse count signal and to said local elevation signal for providing a comparison signal in accordance with the equality and inequality therebetween, a source of clock pulses, and gating means responsive to said clock pulses and to said comparison signal for transmitting said clock pulses to said altitude pulse counting means when said altitude pulse count signal is not equal to said local elevation signal and for interrupting said clock pulses when said altitude pulse count signal is equal to said local elevation signal, said altitude pulse counting means including means for altering said altitude pulse count signal in response to said transmitted clock pulses until said altitude pulse count signal is rendered equal to said local elevation signal, whereby the pulse count of said transmitted clock pulses is proportional to said altitude difference to provide said altitude difference signal.

Claim 10

The system of claim 8 in which said second converter means comprises second variable gain means coupled to said gating means and responsive to said altitude difference signal, altimeter setting indicating means responsive to the output signal of said second variable gain means, second feedback means responsive to the output signal of said altimeter setting indicating means and including second predetermined program means relating pressure altitude around sea level to barometric pressure under standard day conditions, said second variable gain means being responsive to the output signal of said second feedback means for controlling the gain thereof for rendering said output signal of said altimeter setting indicating means proportional to said standard day barometric pressure corresponding to said altitude difference.

Claim 11

The system of claim 9 in which said second program means includes means relating said altitude difference pulse count of said transmitted clock pulses to barometric pressure under standard day conditions, said second variable gain means comprises second variable frequency altering means for altering said altitude difference pulse count in accordance with said output signal of said second feedback means, and said altimeter setting indicating means comprises altimeter setting pulse counting means for providing an altimeter setting pulse count signal in accordance with the altered pulse count from said second frequency altering means, whereby said altimeter setting pulse count signal of said altimeter setting pulse counting means is rendered proportional to the standard day barometric pressure corresponding to said altitude difference.

Claim 12

The system of claim 10 in which said second feedback means comprises a second memory address counter coupled to said altimeter setting pulse counting means for providing a sequence of digital address signals in response to said altimeter setting pulse count signal, and second memory means coupled to said second memory address counter for providing predetermined digital parameter signals in response to said address signals for controlling said second variable fRequency altering means.

Claim 13

The system of claim 11 in which said second variable frequency altering means comprises a binary rate multiplier having one input responsive to said transmitted clock pulses, another input responsive to said digital parameter signals from said second memory means and its output coupled to said altimeter setting pulse counting means.

Claim 14

The system of claim 11 in which said comparator means further provides further comparison signals in accordance with said altitude pulse count signal being greater or less than said local elevation signal, and said altitude pulse counting means comprises an up/down counter responsive to said further comparison signals and to said transmitted clock pulses for counting down when said altitude pulse count signal is greater than said local elevation signal and for counting up when said altitude pulse count signal is less than said local elevation signal.

Claim 15

The system of claim 13 in which said altimeter setting pulse counting means comprises an up/down counter responsive to said further comparison signals and to said altered altitude difference pulse count from said second frequency altering means for counting down when said altitude pulse count signal is greater than said local elevation signal and for counting up when said altitude pulse count signal is less than said local elevation signal, said second converter means includes means for presetting said altimeter setting counter to standard day sea level barometric pressure, and said second memory address counter comprises an up/down counter responsive to said further comparison signals for counting in one direction when said altitude pulse count signal is greater than said local elevation signal and for counting in the opposite direction when said altitude pulse count signal is less than said local elevation signal.

Claim 16

The system of claim 14 further including parallel to serial converter means coupled to said altimeter setting counter for converting said altimeter setting pulse count signal from parallel digital to serial digital format.

Claim 17

The system of claim 15 further including frequency shift keying means responsive to said serial digital signal for providing a serial frequency shift keyed signal corresponding thereto.

Claim 18

The system of claim 15 further including auxiliary coding means responsive to said serial digital signal for providing a serial coded signal corresponding thereto.

Claim 19

The system of claim 17 in which said auxiliary coding means comprises a modem interface.

Claim 20

The system of claim 15 further including display means responsive to said serial digital altimeter setting signal for displaying said altimeter setting pressure.

Claim 21

The system of claim 19 in which said display means comprises serial to parallel converter means responsive to said serial digital altimeter setting signal for converting said signal to parallel format, decoder means responsive to said parallel digital altimeter setting signal for providing readout control signals corresponding thereto, and digital readout means coupled to said decoder means for displaying said altimeter setting pressure in digital format in response to said readout control signals.

Claim 22

The system of claim 19 in which said vibratory pressure sensor means includes a vibratory pressure sensor for providing a cyclic signal with frequency a function of barometric pressure.

Claim 23

The system of claim 21 further including monitoring means comprising a source of monitor signal of predetermined frequency, means for replacing said vibrating pressure sensor signal with said monitor signal, a source of test elevation signal of predetermined value, means for replacing said local elevation signal with said test elevation signal, serial-to-parallel converter means responsive to said serial digital altimeter setting signal for converting said signal to parallel format, means for providing a test altimeter setting pRessure signal representative of the altimeter setting pressure corresponding to said predetermined frequency of said monitor signal and said predetermined value of said test elevation signal, test comparator means responsive to said parallel digital altimeter setting signal and said test altimeter setting signal for providing a failure signal when said parallel digital altimeter setting signal and said test altimeter setting signal fail to compare, and means responsive to said failure signal for inserting signals into said parallel-to-serial converter means for controlling said display means to display failure indicia.

Claim 24

The system of claim 10 further including digital indicator and decoding means responsive to the output of said altimeter setting pulse counting means for displaying said altimeter setting pressure.

Claim 25

The system of claim 1 in which said second converter means comprises second variable gain means responsive to said altitude difference signal, altimeter setting indicating means responsive to the output signal of said second variable gain means, second feedback means responsive to the output signal of said altimeter setting indicating means and including second predetermined program means relating pressure altitude to barometric pressure under standard day conditions, said second variable gain means being responsive to the output signal of said second feedback means for controlling the gain thereof for rendering said output signal of said altimeter setting indicating means proportional to said standard day barometric pressure corresponding to said altitude difference.

Claim 26

A digital altimeter setting indiciator system comprising a vibratory pressure sensor for providing a cyclic signal with frequency a function of local barometric pressure, a sensor counter responsive to said cyclic signal for providing a gating pulse of width in accordance with a predetermined number of cycles thereof, a source of clock pulses, first gating means responsive to said clock pulses and to said gating pulse for transmitting said clock pulses during the occurrence of said gating pulse thereby providing groups of pulses of pulse count in accordance with said local barometric pressure, a first binary rate multiplier having a pulse train input responsive to said groups of pulses, a digital control input and a pulse train output for altering said pulse counts in accordance with said digital control input, an altitude up/down pulse counter coupled to said pulse train output of said first binary rate multiplier for providing a digital altitude pulse count signal in accordance with said altered pulse counts, a first memory address counter coupled to said altitude counter for providing a sequence of first digital address signals in response to said altitude pulse count signal, a first memory coupled to said first memory address counter for storing first digital parameter signals relating said sensor pulse counts to pressure altitude under standard day conditions and for providing said digital parameter signals in response to said first address signals, said digital control input of said first binary rate multiplier being coupled to receive said first digital parameter signals for rendering said altitude pulse count signal proportional to local pressure altitude under standard day conditions in response to said pressure sensor signal, settable means for providing a digital signal corresponding to actual local elevation, a digital comparator responsive to said altitude pulse count signal and said local elevation signal for providing a comparison signal in accordance with the equality therebetween and for providing further comparison signals in accordance with said altitude pulse count signal being greater or less than said local elevation signal, second gating means responsive to said clock pulses and to said comparison signal for transmitting said clock pulses to said altitude pulse counter When said altitude pulse count signal is not equal to said local elevation signal and for interrupting said clock pulses when said altitude pulse count signal is equal to said local elevation signal, said altitude pulse counter being responsive to said transmitted clock pulses and to said further comparison signals for counting down when said altitude pulse count signal is greater than said local elevation signal and for counting up when said altitude pulse count signal is less than said local elevation signal until said altitude pulse count signal is rendered equal to said local elevation signal, whereby the pulse count of said transmitted clock pulses is proportional to the altitude difference between said altitude pulse count signal and said local elevation signal, a second binary rate multiplier having a pulse train input responsive to said transmitted altitude difference clock pulses, a digital control input and a pulse train output for altering said pulse count of said transmitted clock pulses in accordance with said digital control input, an altimeter setting up/down pulse counter coupled to said pulse train output of said second binary rate multiplier and responsive to said further comparison signals for counting down when said altitude pulse count signal is greater than said local elevation signal and for counting up when said altitude pulse count signal is less than said local elevation signal to provide a digital altimeter setting pulse count signal in accordance with said altered pulse count of said transmitted clock pulses, means for presetting said altimeter setting counter to standard day sea level barometric pressure, a second memory address up/down counter coupled to said altimeter setting counter and responsive to said further comparison signals for counting in one direction e27 aid altitude pulse count signal is greater than said local elevation signal and for counting in the opposite direction when said altitude pulse count signal is less than said local elevation signal to provide a sequence of second digital address signals in response to said altimeter setting pulse count signal, a second memory coupled to said second memory address counter for storing digital parameter signals relating said altitude difference pulse count of said transmitted clock pulses to barometric pressure around sea level under standard day conditions and for providing said digital parameter signals in response to said second address signals, said digital control input of said second binary rate multiplier being coupled to receive said second digital parameter signals for rendering said altimeter setting pulse count signal proportional to the standard day barometric pressure corresponding to said altitude difference thereby providing said altimeter setting pressure, means for transmitting said altimeter setting pulse count signal, and a display means responsive to said transmitted altimeter setting pulse count signal for displaying said altimeter setting pressure in digital format.

Claim 27

A digital altimeter setting indiciator system comprising a vibratory pressure sensor for providing a cyclic signal with frequency a function of local barometric pressure, a sensor counter responsive to said cyclic signal for providing a gating pulse of width in accordance with a predetermined number of cycles thereof, a source of clock pulses, first gating means responsive to said clock pulses and to said gating pulse for transmitting said clock pulses during the occurrence of said gating pulse thereby providing groups of pulses of pulse count in accordance with said local barometric pressure, a first binary rate multiplier having a pulse train input responsive to said groups of pulses, a digital control input and a pulse train output for altering said pulse counts in accordance with said digital control input, an altitude up/down pulse counter coupled to said pulse train output of said first binary rate multiplier for providing a digital altitude pulse count signal in accordance with said altered pulse counts, a first memory address counter coupled to said altitude counter for providing a sequence of first digital address signals in response to said altitude pulse count signal, a first memory coupled to said first memory address counter for storing first digital parameter signals relating said sensor pulse counts to pressure altitude under standard day conditions and for providing said digital parameter signals in response to said first address signals, said digital control input of said first binary rate multiplier being coupled to receive said first digital parameter signals for rendering said altitude pulse count signal proportional to local pressure altitude under standard day conditions in response to said pressure sensor signal, settable means for providing a digital signal corresponding to actual local elevation, a digital comparator responsive to said altitude pulse count signal and said local elevation signal for providing a comparison signal in accordance with the equality therebetween and for providing further comparison signals in accordance with said altitude pulse count signal being greater or less than said local elevation signal, second gating means responsive to said clock pulses and to said comparison signal for transmitting said clock pulses to said altitude pulse counter When said altitude pulse count signal is not equal to said local elevation signal and for interrupting said clock pulses when said altitude pulse count signal is equal to said local elevation signal, said altitude pulse counter being responsive to said transmitted clock pulses and to said further comparison signals for counting down when said altitude pulse count signal is greater than said local elevation signal and for counting up when said altitude pulse count signal is less than said local elevation signal until said altitude pulse count signal is rendered equal to said local elevation signal, whereby the pulse count of said transmitted clock pulses is proportional to the altitude difference between said altitude pulse count signal and said local elevation signal, a second binary rate multiplier having a pulse train input responsive to said transmitted altitude difference clock pulses, a digital control input and a pulse train output for altering said pulse count of said transmitted clock pulses in accordance with said digital control input, an altimeter setting up/down pulse counter coupled to said pulse train output of said second binary rate multiplier and responsive to said further comparison signals for counting down when said altitude pulse count signal is greater than said local elevation signal and for counting up when said altitude pulse count signal is less than said local elevation signal to provide a digital altimeter setting pulse count signal in accordance with said altered pulse count of said transmitted clock pulses, means for presetting said altimeter setting counter to standard day sea level barometric pressure, a second memory address up/down counter coupled to said altimeter setting counter and responsive to said further comparison signals for counting in one direction e27 aid altitude pulse count signal is greater than said local elevation signal and for counting in the opposite direction when said altitude pulse count signal is less than said local elevation signal to provide a sequence of second digital address signals in response to said altimeter setting pulse count signal, a second memory coupled to said second memory address counter for storing digital parameter signals relating said altitude difference pulse count of said transmitted clock pulses to barometric pressure around sea level under standard day conditions and for providing said digital parameter signals in response to said second address signals, said digital control input of said second binary rate multiplier being coupled to receive said second digital parameter signals for rendering said altimeter setting pulse count signal proportional to the standard day barometric pressure corresponding to said altitude difference thereby providing said altimeter setting pressure, means for transmitting said altimeter setting pulse count signal, and a display means responsive to said transmitted altimeter setting pulse count signal for displaying said altimeter setting pressure in digital format.