Signal processing apparatus

Claim 2

Signal processing apparatus for deriving a digital representation of theta from signals proportional to sin theta and cos theta including: a. synthesizing means responsive to said signals proportional to sin theta and cos theta for deriving therefrom a signal proportional to sin theta / theta ; b. integrating means operably connected to said synthesizing means and responsive to said signals proportional to sin theta and sin theta / theta for integrating one of said signals in one direction for a time t1 and the other of said signals in the opposite direction for a time t2 until the output of said integrating means returns to its original state; and c. counting/processing means operably connected to said integrating means and responsive thereto for deriving therefrom a digital representation of theta .

Claim 3

Apparatus according to claim 1 wherein said signals proportional to sin theta and cos theta are derived from resolver-type signals proportional to sin theta sinwt and cos theta sinwt.

Claim 4

Signal processing apparatus for deriving a digital representation of theta from signals proportional to sin theta and cos theta including: a. synthesizing means responsive to said signals proportional to sin theta and cos theta for derivinG therefrom an output signal proportional to sin theta / theta ; b. summing means operably connected to said synthesizing means and responsive to said signals proportional to sin theta and sin theta / theta for developing therefrom a composite signal proportional to sin theta and sin theta / theta ; c. switching means operably connected to said synthesizing means and responsive to said signals proportional to sin theta and sin theta / theta for selecting one of said signals; d. integrating means operably connected to said summing means and said switching means and responsive to said selected signal and said composite signal for integrating one of said signals in one direction for a time t1 and the other of said signals in the opposite direction for a time t2 until the output of said integrating means returns to its original state; and e. counting/processing means operably connected to said integrating means and responsive thereto for deriving therefrom a digital representation of theta .

Claim 5

Signal processing apparatus for deriving a digital representation of theta from signals proportional to sin theta and cos theta including: a. synthesizing means responsive to said signals proportional to sin theta and cos theta for derivinG therefrom an output signal proportional to sin theta / theta ; b. summing means operably connected to said synthesizing means and responsive to said signals proportional to sin theta and sin theta / theta for developing therefrom a composite signal proportional to sin theta and sin theta / theta ; c. switching means operably connected to said synthesizing means and responsive to said signals proportional to sin theta and sin theta / theta for selecting one of said signals; d. integrating means operably connected to said summing means and said switching means and responsive to said selected signal and said composite signal for integrating one of said signals in one direction for a time t1 and the other of said signals in the opposite direction for a time t2 until the output of said integrating means returns to its original state; and e. counting/processing means operably connected to said integrating means and responsive thereto for deriving therefrom a digital representation of theta .

Claim 6

Signal processing apparatus for deriving a digital representation of theta from a signal proportional to sin(wt + theta ) and a reference signal including: a. synthesizing means responsive to said signal proportional to sin(wt + theta ) and said reference signal for deriving therefrom signals proportional to sin theta and sin theta / theta ; b. integrating means operably connected to said synthesizing means and responsive to said signals proportional to sin theta and sin theta / theta for integrating one of said signals in one direction for a time t1 and the other of said signals in the opposite direction for a time t2 until the output of said integrating means returns to its original state; and c. counting/processing means operably connected to said integrating means and responsive thereto for deriving therefrom a digital representation of theta .

Claim 7

Signal processing apparatus for deriving a digital representation of theta from a signal proportional to sin(wt + theta ) and a reference signal including: a. synthesizing means responsive to said signal proportional to sin(wt + theta ) and said reference signal for deriving therefrom signals proportional to sin theta and sin theta / theta ; b. integrating means operably connected to said synthesizing means and responsive to said signals proportional to sin theta and sin theta / theta for integrating one of said signals in one direction for a time t1 and the other of said signals in the opposite direction for a time t2 until the output of said integrating means returns to its original state; and c. counting/processing means operably connected to said integrating means and responsive thereto for deriving therefrom a digital representation of theta .

Claim 8

Apparatus according to claim 4 further including display means operably connected to said counting/processing means and responsive thereto for digitally displaying theta in degrees.

Claim 9

Apparatus according to claim 4 wherein said synthesizing means includes means for deriving from said signal proportional to sin(wt+ theta ) signals proportional to sin theta and cos theta and means for synthesizing therefrom said signal proportional to sin theta / theta .

Claim 10

Apparatus according to claim 6 wherein said means for synthesizing said signal proportional to sin theta / theta includes piecewise approximation means.

Claim 11

Apparatus according to claim 4 wherein said synthesizing means includes means for incorporating a scale factor into at least one of said signals proportional to sin theta and sin theta / theta for facilitating the conversion of theta from radians to degrees.

Claim 12

Signal processing apparatus for deriving a digital representation of a theta from a signal proportional to sin(wt+ theta ) and a reference signal including: a. synthesizing means responsive to said signal proportional to sin(wt+ theta ) and said reference signal for deriving therefrom signals proportional to sin theta and sin theta / theta ; b. integrating means operably connected to said synthesizing means and responsive thereto for integrating said signal proportional to sin theta in one direction for a time t1 and said signal proportional to sin theta / theta in the opposite direction for a time t2 until said integrating means returns to its original state; and c. counting means operably connected to said integrating means and responsive thereto for counting during said time period t2 to generate a digital representation directly proportional to theta .

Claim 13

Signal processing apparatus for deriving a digital representation of a theta from a signal proportional to sin(wt+ theta ) and a reference signal including: a. synthesizing means responsive to said signal proportional to sin(wt+ theta ) and said reference signal for deriving therefrom signals proportional to sin theta and sin theta / theta ; b. integrating means operably connected to said synthesizing means and responsive thereto for integrating said signal proportional to sin theta in one direction for a time t1 and said signal proportional to sin theta / theta in the opposite direction for a time t2 until said integrating means returns to its original state; and c. counting means operably connected to said integrating means and responsive thereto for counting during said time period t2 to generate a digital representation directly proportional to theta .

Claim 14

Apparatus according to claim 9 wherein said synthesizing means includes means for incorporating a scale factor into at least one of said signals proportional to sin theta and sin theta / theta for facilitating the conversion of theta from radians to degrees.

Claim 15

Apparatus according to claim 9 wherein said synthesizing means incLudes means for deriving said signal proportional to sin theta / theta over an octant and further includes switching means for utilizing said signal proportional to sin theta / theta over all eight octants.

Claim 16

Apparatus according to claim 11 wherein said synthesizing means includes segment sensing and switching means for deriving a piecewise approximation of said signal proportional to sin theta / theta over an octant.

Claim 17

Apparatus according to claim 12 wherein said segment sensing and switching means effects said piecewise approximations of said signal proportional to sin theta / theta over three segments comprising an octant and wherein said segments comprise on the order of 23*, 12* and 10*.

Claim 18

Apparatus according to claim 11 wherein said switching means includes octant sensing and switching means for presetting said counting means and for controlling the direction of counting of said counting means.

Claim 19

Apparatus according to claim 9 wherein said synthesizing means includes phase-locked loop means responsive to said reference signal for generating a plurality of chopping waveforms and demodulator means operably connected to said phase locked loop means and responsive thereto and to said signal proportional to sin(wt+ theta ) for deriving therefrom signals proportional to sin theta and cos theta for use in deriving said signals proportional to sin theta and sin theta / theta .

Claim 20

Apparatus according to claim 15 wherein said chopping waveforms are pi /6 chopping waveforms.

Claim 21

Signal processing apparatus for deriving a digital representation of theta from a signal proportional to sin(wt+ theta ) and a reference signal including: a. circuit means responsive to said signal proportional to sin(wt+ theta ) and said reference signal for deriving therefrom signals proportional to sin theta and cos theta ; b. synthesizing means operably connected to said circuit means and responsive thereto for deriving therefrom an output signal proportional to sin theta / theta ; c. summing means operably connected to said circuit means and said synthesizing means and responsive thereto for developing a composite signal proportional to sin theta and sin theta / theta ; d. switching means operably connected to said circuit means and said synthesizing meand and adapted for selecting one of said signals proportional to sin theta and sin theta / theta ; e. integrating means operably connected to said switching means and said summing means and responsive to said selected signal and said composite signal for integrating one of said signals in one direction for a time t1 and the other of said signals in the opposite direction for a time t2 until the output of said integrating means returns to its original state; and f. counting/processing means operably connected to said integrating means and responsive thereto for deriving therefrom a digital representation of theta .

Claim 22

Signal processing apparatus for deriving a digital representation of theta from a signal proportional to sin(wt+ theta ) and a reference signal including: a. circuit means responsive to said signal proportional to sin(wt+ theta ) and said reference signal for deriving therefrom signals proportional to sin theta and cos theta ; b. synthesizing means operably connected to said circuit means and responsive thereto for deriving therefrom an output signal proportional to sin theta / theta ; c. summing means operably connected to said circuit means and said synthesizing means and responsive thereto for developing a composite signal proportional to sin theta and sin theta / theta ; d. switching means operably connected to said circuit means and said synthesizing meand and adapted for selecting one of said signals proportional to sin theta and sin theta / theta ; e. integrating means operably connected to said switching means and said summing means and responsive to said selected signal and said composite signal for integrating one of said signals in one direction for a time t1 and the other of said signals in the opposite direction for a time t2 until the output of said integrating means returns to its original state; and f. counting/processing means operably connected to said integrating means and responsive thereto for deriving therefrom a digital representation of theta .

Claim 23

Apparatus according to claim 17 wherein said synthesizing means includes means for incorporating a scale factor into said signal proportional to sin theta / theta for facilitating conversion of theta from radians to degrees.