Abstract: An analog converter for a motor angle sensor is described. The analog converter for a motor angle sensor includes Gilbert Cells configured to receive a signal from a motor angle sensor, an intermediate frequency signal source configured to provide an excitation signal to the Gilbert Cells, a low-pass filter configured to receive an output from the Gilbert Cells, a Scott transformer to convert a three-phase waveform into a two-phase waveform, and output a converted signal to an electronic controller.

Abstract: Techniques are described that allow an air traffic display of an aircraft to display the relative motion of air traffic proximate to the aircraft. The air traffic display may be switched between a first display mode in which absolute motion of air traffic is displayed (e.g., motion of air traffic targets relative to a fixed point on the earth's surface or relative to an apparently fixed celestial point is displayed) and a second display mode in which motion of air traffic targets is displayed relative to the aircraft. The techniques further facilitate the selection of individual traffic targets from a displayed traffic depiction to activate a third display mode in which additional information about the relative motion of the selected target, such as its estimated closest point of approach (CPA) to the aircraft and the estimated time it will take the selected target to reach the CPA are shown.

Abstract: A phase digitizing system includes an analog-to-digital converter (ADC), multiple phase accumulators and a processing device. The ADC generates sample segments of digital signal waveform samples based on an analog composite input signal received in a measurement channel, the composite input signal includes a first signal having a first frequency F1 and a second signal imported from a reference channel having a second frequency F2. The processing device is coupled to the phase accumulators, and digitally processes each sample segment with outputs of the phase accumulators, and continually generates digital phase data The processing device further provides increment values to each of the phase accumulators based on the digital phase data, causing an output of a first phase accumulator to represent an instantaneous phase of the first signal, and an output of a second phase accumulator to represent an instantaneous phase of the second signal.

Abstract: A motor control device determines a rotation angle and an angular speed of a motor, and has: a correcting unit including N number (N is an positive integer equal to or more than 2) of bit-shift circuits, which divide the angular speed by powers of 2 by bit shift, and a circuit, which subtracts output values of the second to Nth bit-shift circuits from an output value of the first bit-shift circuit to determine a correction amount for the rotation angle and correct the rotation angle by the correction amount; so as to determine two-phase direct voltages to obtain a target torque from the three-phase alternate currents passing through the motor according to the angular speed, and convert the two-phase direct voltages into the three-phase alternate voltages according to the sine, cosine of the corrected rotation angle.

Abstract: A digital-to-synchro converter (“DSC”) is a device that converts digital signals to analog signals suitable for use by a synchro device. A conventional DSC implements complex circuitry to take digital input and generate [V Sin({acute over (?)}t) Sin(?)] and [V Sin({acute over (?)}t) Cos(?)] analog signals, and a Scott-T transformer to transform these analog signals into [V Sin({acute over (?)}t) Sin(?)], [V Sin({acute over (?)}t) Sin(?+120)], and [V Sin({acute over (?)}t) Sin(?+240)] analog signals. An inventive DSC, as typically embodied, implements a microcontroller to take digital input and generate [V Sin({acute over (?)}t) Sin(?)] and [V Sin({acute over (?)}t) Sin(?+120)] digital signals, a digital-to-analog converter to convert these digital signals to [V Sin({acute over (?)}t) Sin(?)] and [V Sin({acute over (?)}t) Sin(?+120)] analog signals, and a regular transformer (i.e.

Abstract: A method is presented for converting the sine/cosine signals from an optical encoder into a high-resolution position signal for use by a position control system while eliminating common noise and error sources. The improved noise performance resulting from the alias-free demodulation of encoder signals improves precision and reduces power consumption in precision motion control applications. The adaptive compensation of harmonic distortion eliminates errors related to offset, gain and quadrature of the encoder channels. The interpolator is able to process encoder signals at extremely high resolution without the speed limitation of prior art encoder interpolators.

Abstract: An interface system between an RDC and a connected resolver dynamically matches an input range of the RDC to the output range of the resolver's output signals. The interface system may include methods and/or apparatuses to determine the amplitude of sinusoidal input signals presented to the RDC by the resolver and to compare the amplitude against high and low threshold values. A gain control signal may be generated, which may be corrected if the detected amplitude either exceeds the high threshold or falls below the low threshold. The gain control signal may be output to a circuit in the RDC or in the resolver that corrects any mismatch that occurs between the RDC input and the resolver output. For example, the gain control signal may control the amplitude of an excitation signal applied to a primary of the resolver or the gain control signal may be applied to an analog to digital converter at the input of the RDC to control its effective input range.

Abstract: A system and method for reducing noise in resolver-to-digital converters (RDC) using a cascaded tracking loop filter. In some embodiments, one or more tracking loop filters may be implemented in a cascade to attenuate carrier harmonic frequencies in the digitized output of an RDC. Where a plurality of tracking loop filters are implemented, the output of one tracking loop filter may be input into a successive tracking loop filter.

Abstract: A control device for a travel motor mounted to a vehicle has a resolver which works as a rotation-angle sensor. The control device has a RDC which calculates a rotation-angle output value ? based on rotation detection signals Sa, Sb transferred from the resolver. The control device supplies electric power to the travel motor based on the rotation angle output value ?. The RDC calculates “sin(???)” as an error deviation ? based on the signals Sa and Sb and the rotation-angle output value ?. The RDC calculates an angular acceleration by multiplying the error deviation ? with a gain (=Ka·Kb), and integrates the angular acceleration two times in order to obtain a next rotation-angle output value. A gain control part of the RDC decreases the gain when the judgment means judges that the travel motor rotates at a constant rotation speed.

Abstract: A method is provided for operating an electromechanical actuator comprising a movable element, a position sensor for detecting the position of the movable element, a logic unit connected to the position sensor, and exactly one output line for the logic unit to transmit a pulse width modulated (PWM) signal having a predetermined frequency value, the method providing for the logic unit to perform detecting a position of the movable element, determining a value of a duty cycle of the pulse width modulated (PWM) signal on the basis of the detected position of the movable element, and transmitting a pulse width modulated (PWM) signal indicative of the position of the movable element having the determined value of the duty cycle.

Abstract: A reference signal generation circuit generates a reference signal used in synchronous detection for removing an excitation signal component in an angle calculation section that converts a detection angle ? obtained from two-phase resolver detection signals output from a resolver, to a digital output angle ?. The reference signal generation circuit includes a first multiplier, a second multiplier, and an adder. The first multiplier multiplies one of the resolver detection signals sin ? sin(?t+??) by the sine value sin ? of the digital output angle ? obtained from the angle calculation section. The second multiplier multiplies the other resolver detection signal cos ? sin(?t+??) by the cosine value cos ? of the digital output angle ? obtained from the angle calculation section. The adder adds the output of the first multiplier and the output of the second multiplier to output the sum signal sin(?t+??) as the reference signal.

Abstract: A rotary electrostatic encoder comprising a disk-shaped fixed plate having a first transmission electrode, a second transmission electrode, and four reception electrodes; a disk-shaped rotating plate having a first induction electrode superposed on and facing the first transmission electrode, and a second induction electrode positioned on the inside of the first induction electrode and superposed on and facing the second transmission electrode, a portion of the second induction electrode being a protruding eccentric circular part; transmission means for applying a transmission signal between the first transmission electrode and the second transmission electrode; and signal processing means for generating an output signal relating to the absolute rotational displacement of the rotating plate on the basis of two signal components generated from the four reception electrodes.

Abstract: A signal conditioning circuit time share multiplexes anti-aliasing filters and an A/D converter. A plurality of first tier multiplexers each time share multiplex one of a plurality of antialiasing filters between a plurality of AC or baseband input signals from a plurality of sensors. A second tier multiplexer selects its inputs from the outputs of the first tier multiplexers. The output of the second tier multiplexer feeds a high speed A/D converter. Thus, the A/D converter is time share multiplexed by the second tier multiplexer. In this manner, a plurality of sensors can share a single A/D converter. After allowing a settling time for the multiplexers and antialiasing filters, a plurality of samples of the input signals are taken, such as for one period. The samples of each AC input signal are multiplied by a sine vector and a cosine vector. The product vectors are then each averaged and the root mean square of the two averages yields the magnitude of the input signal.

Abstract: A signal conditioning circuit time share multiplexes anti-aliasing filters and an A/D converter. A plurality of first tier multiplexers each time share multiplex one of a plurality of antialiasing filters between a plurality of AC or baseband input signals from a plurality of sensors. A second tier multiplexer selects its inputs from the outputs of the first tier multiplexers. The output of the second tier multiplexer feeds a high speed A/D converter. Thus, the A/D converter is time share multiplexed by the second tier multiplexer. In this manner, a plurality of sensors can share a single A/D converter. After allowing a settling time for the multiplexers and antialiasing filters, a plurality of samples of the input signals are taken, such as for one period. The samples of each AC input signal are multiplied by a sine vector and a cosine vector. The product vectors are then each averaged and the root mean square of the two averages yields the magnitude of the input signal.

Abstract: An A/D conversion apparatus performs motor current detection in an A/D conversion period corresponding to two phases out of three phases of a sinusoidal drive motor, using reduced register resources while minimizing the number of A/D converters. The A/D conversion apparatus includes: a selection unit selecting one of a plurality of input channels; an A/D converter converting an analog signal from the selected input channel to a digital signal; a start register holding a start channel number of sequential conversion; an end register holding an end channel number of the sequential conversion; a prohibition information holding unit holding prohibition information indicating an input channel to be excluded from the sequential conversion; and a control unit causing the selection unit to select, in channel number order, input channels corresponding to channel numbers from the start channel number to the end channel number except the input channel indicated by the prohibition information.

Abstract: The invention provides an angular position detector that can be configured at low cost and that accurately detects the angular position of a rotor in a rotary electric device and permits reliable control thereof even when the rotary electric device runs at a high speed. The angular position detector includes a resolver that outputs a signal indicating the rotational angle of the rotor and a signal processing circuit that calculates the rotational angle of the rotor based on the signal output from the resolver. The signal processing circuit samples output signals from the resolver at predetermined intervals and converts the signal into a digital signal. By calculating the angular speed according to the digital signal output from the resolver, the computation process is simpler, and can be performed using a microcomputer with less processing power, which reduces the component costs for the angular position detector.

Abstract: A small-sized and low-cost phase detection circuit which has improved noise immunity. The phase detection circuit comprises a multiplier for multiplying an input signal by a reference signal and outputting a first signal, an integration circuit for integrating the first signal and outputting a second signal, a phase estimation circuit for estimating phase information based on the second signal, and a reference signal generation circuit for generating the reference signal based on the estimated phase information. Since the phase is detected based on information representing an entire waveform, the influence of local noise can be diluted and noise immunity can be improved.

Abstract: A signal conditioning circuit time share multiplexes anti-aliasing filters and an A/D converter. A plurality of first tier multiplexers each time share multiplex one of a plurality of antialiasing filters between a plurality of AC or baseband input signals from a plurality of sensors. A second tier multiplexer selects its inputs from the outputs of the first tier multiplexers. The output of the second tier multiplexer feeds a high speed A/D converter. Thus, the A/D converter is time share multiplexed by the second tier multiplexer. In this manner, a plurality of sensors can share a single A/D converter. After allowing a settling time for the multiplexers and antialiasing filters, a plurality of samples of the input signals are taken, such as for one period. The samples of each AC input signal are multiplied by a sine vector and a cosine vector. The product vectors are then each averaged and the root mean square of the two averages yields the magnitude of the input signal.

Abstract: A method for providing a correlation between a periodic analog/digital conversion and an angle-synchronous signal, in which the periodic analog/digital conversion is provided with a timing mark, which correlates with the angle-synchronous signal, and is assigned to an angular position of a device via this timing mark.

Abstract: Method for coding at least one datum using three digital signals A, B, C delivered on respectively one channel, in which the third signal C is delivered by a combination of the first two signals A, B in order to form m binary triplets, where m<8. The method provides for modifying the third signal C according to the data to be coded in order to generate n binary triplets, where n>1, the n triplets being different from the m triplets. A device for determining the absolute angular position of a turning member is described.

Abstract: Since an abnormality is judged by executing a square calculating process with respect to sin ? and cos ? for detecting an abnormality in an angular resolver, a processing time is elongated, and a burden to a CPU is great. Since the invention prepares a map which can judge whether the combination of sin ? and cos ? is normal or abnormal, and judges by mapping the combination of the detected sin ? and cos ?, a process can be easily executed, a processing speed is high, and a burden to the CPU can be reduced. Further, an assist can be maintained by controlling a motor by a rectangular wave current by detecting a rotation angle signal at low resolution level, such as Hall sensors arranged around the motor.

Abstract: An interpolation apparatus in an encoder includes an analog-to-digital converter for digitizing a sine wave signal and a cosine wave signal, respectively. An amplitude level detecting circuit detects each amplitude level of the digitized sine wave signal and cosine wave signal. A computing circuit multiplies the amplitude level of one of the signal by an interpolation position parameter according to a tangent value at an interpolation position. A comparing circuit compares an output from the computing circuit to an output from the amplitude level detecting circuit. The comparison is made at every the interpolation position. A region detecting circuit identifies a region sectionalized by the interpolation positions adjacent to each other based on an output from the comparing circuit corresponding to each the interpolation position. The phase angle of the sine wave signal and the cosine wave signal exists in the region.

Abstract: An apparatus for transmitting a position detection signal of a multi-shaft motor whereby a parallel-form detection signal that is output from position-detecting devices disposed on each of a plurality of motors and used for indicating a motor rotation position can be transmitted to motor drivers for controlling the driving of the motors via a group of a small number of wires. In the apparatus for transmitting a position detection signal of a multi-shaft motor, a transmission-side converter converts a parallel-form detection signal from rotary encoders to a serial signal and presents the resulting signal to a reception-side converter via a serial signal transmission path. The reception-side converter returns the received serial-form detection signal to a parallel-form signal and presents the signal to motor drivers.

Abstract: A logic device for the transformation of the output of the RDC into series A-B pulses according to the present invention comprises: a chip with its two minimal bits (LSB-LSB-1) simulating as the clock source of A-B pulses, a signal-processing pin (BUSY) which output a TTL pulse wave as a control signal resource while LSB shifts from a low level to a high level and contrariwise, and a logic processing circuit as well as a buffer to output the displacement and velocity of a rotor in the form of A-B serial pulses.

Abstract: A resolver-to-digital converting apparatus calculates a resolver rotational angle from two-phase sampling values that are the result of sampling two-phase output signals, which are obtained from a single-phase-excited, two-phase output resolver, at peak timings of a waveform. The apparatus includes a determination unit for determining whether each of the two-phase sampling values has deviated from a prescribed path of rotation by more than a predetermined amount when the two-phase sampling values are represented by orthogonal coordinates; a correction processing unit, responsive to a determination that the predetermined amount has been exceeded, for applying a correction to the two-phase sampling values using an equation of a tangent to the path of rotation at a point on the path of rotation at which the previous resolver rotational angle was obtained; and an angle calculation unit for obtaining a resolver rotational angle at the corrected two-phase sampling values obtained by correction processing.

Abstract: The lateral double-diffused MOS transistor includes a drift region of a first conductive type provided on a semiconductor substrate of a second conductive type, and a body diffusion region of the second conductive type formed on the surface within the drift region. The MOS transistor includes a gate electrode formed in such a position as it covers from part of the body diffusion region to part of the drift region located outside the diffusion region via an insulating film. The MOS transistor further includes a source diffusion region of the first conductive type and a drain diffusion region of the first conductive type formed on top of the body diffusion region and top of the drift region, respectively, both of which correspond to both sides of the gate electrode. The drain diffusion region includes a deep diffusion portion which has a 1/1000 or more concentration of a peak concentration of the source diffusion region and which is positioned deeper than the source diffusion region.

Abstract: A resolver can make accurate angle detection in an entire detection range. The resolver includes a resolver stator having an excitation winding of one phase adapted to be excited by a power supply and a first and a second output winding of two phases for outputting a change in the density of magnetic flux as a voltage, a resolver rotor arranged at a central portion of the resolver stator so as to cooperate with the resolver stator for changing a gap permeance between the resolver rotor and the resolver stator in accordance with the rotation of the resolver rotor, and a detection error correction part that corrects an angle detection error of the resolver by using the value of a Lissajous radius of a circular Lissajous waveform obtained from the amplitudes of an output signal Scos from the first output winding and an output signal Ssin from the second output winding.

Abstract: A drive circuit for a flat display apparatus is disclosed wherein different display objects can be displayed at a time individually with appropriate gamma characteristics. Reference voltages are produced in a plurality of systems having different gamma characteristics from each other, and one of the systems is selected in response to a selection signal. Then, the reference voltages of the selected system are selected in response to image data to set gradations of pixels.

Abstract: A resolver use angle detection IC subjected to a phase lock operation so as to follow not an angle ?(t) for detection, but a phase angle ?ot±?(t) having an offset of a frequency ?ot in the phase lock units. For this reason, when the excitation frequency ?ot is set sufficiently high with respect to the frequency of the angle ?(t), the phase angle ?ot±? to be followed in the phase lock units will not become zero. For this reason, an angle having a high precision can be found in real time regardless of the configuration not including the conventional apparatus in which the configuration is complex and the power consumption is large like a bipolar VCO and an up/down type counter.

Abstract: A device for effectuating a digital estimate of a periodic electric signal is described. The device comprising a linear DAC having an output signal, a comparator that compares the output signal of the linear DAC with the periodic electric signal, and logic circuitry having in input the output signal of the comparator and a pulse clock signal. The logic circuitry provides a first digital signal in input to the linear DAC and a second digital signal representative of the estimate of the periodic electric signal.

Abstract: The invention concerns a method for determining a numerical value for the duration of a periodically repeating pulsed signal. This method comprises the following steps: a) at time intervals, the period length of the signal is determined; b) at time intervals, a characteristic magnitude for the length of a pulse of that signal is determined; c) a numerical value that characterizes the signal is ascertained from the period length and the characteristic magnitude. Because of its shortness and accuracy, the method is particularly suitable for use in electric motors. A corresponding arrangement is also presented and described.

Abstract: Methods and systems for simply and inexpensive converting the signals of solid-state sensors for use by analog systems and indicators. An embodiment of the system receives a DC voltage value from at least one sensor, converts the DC voltage value into one or more analog signals based on a reference AC voltage signal, and performs at least one of outputting or storing the generated analog signals. The conversion is performed digitally then converted to analog or is performed using an analog trigonometric converter.

Abstract: An R/D converter allows high precision detection of a rotation angle of a rotor axis of a resolver having high rates of rotation. An A/D converter is built into a digital signal processor and converts a sine wave and cosine wave output from the resolver. An axis angle calculator calculates tan ?=A((sin ?t)(sin ?))/A((sin ?t)(cos ?)) from A(sin ?t)(sin ?) and A(sin ?t)(cos ?) and further calculates ?=tan?1 ?. The angle space is divided into quadrants and an offset value is set for each quadrant and by adding or subtracting the calculated ? to or from the offset value to form the final angle of the rotor axis of the resolver.

Abstract: The invention relates to a device and a method for determining an electrical starting rotor angle of an electromotor. According to the invention, the electromotor (10) is subjected to an approximately sinusoidal voltage and the corresponding current path (i) that is established is then detected. The electromotor (10) is again subjected to an approximately sinusoidal voltage and again, the corresponding current path (i) is detected. A ratio of a measure of the fundamental wave (I1) and the measure of the first harmonic wave (I2) is then determined from the current paths (i) as a measure of the electrical starting rotor angle (?).

Abstract: This resolver/digital converter has a resolver, a resolver/digital converting portion and an exciting signal generator. The exciting signal generated from the exciting signal generator is supplied to the resolver, and the resolver signals produced from the resolver are supplied to the resolver/digital converter. This resolver/digital converter further has a conversion trigger generator that generates a conversion trigger signal on the basis of the exciting signal generated from the exciting signal generator, an A/D converter that converts the resolver signals produced from the resolver to digital values in response to the conversion trigger signal generated from the conversion trigger generator, and computing means that detects the failure status on the basis of the digital values produced from the A/D converter.

Abstract: A resolver output correction device receives sine output signal and cosine output signal from a resolver. Each of the sine output signal and the cosine output signal has an offset error and a gain differential error due to a secular variation. The correction device detects maximal and minimal values with respect to both the sine output signal and the cosine output signal. It calculates average values between the maximal values and the minimal values. Then, it corrects the offsets of the signals based on the average values. It also calculates gain differentials between the maximal value and the minimal value with respect to both the sine and cosine signals. Then, it corrects the gain differentials of the signals based on the calculated gain differentials. As a result, both the offset and gain errors of the signals are corrected with accuracy.

Abstract: A method for providing a digital current signal from an analog armature current signal of a motor. The method includes subjecting the analog current signal to an analog-to-digital conversion to produce a first digital current signal having current ripples for each current ripple of the analog current signal. During start-up and run-down motor operation phases, the analog current signal is sampled at a sampling rate which is greater than an expected rate of the current ripples of the analog current signal to produce a second digital current signal having current ripples for each current ripple of the analog current signal during the start-up and run-down motor operation phases. The current ripples of the first and second digital current signals are then compared. The current ripples of the second digital current signal which are in non-conformance with the current ripples of the first digital current signal are evaluated.

Abstract: Vibration signals (20, 21) are filtered and integrated (26) and converted to digital signals (41), resolved into orthogonal components (82, 180, 185; 96, 140, 145) of angles (81, 95) related to rotary components (43, 90). The pulse frequency of a stream of input pulses from the rotary components is multiplied (45, 92) by 2n, by inserting (32) a pulse for each ½n fraction (26, 28, 31) of the period (11, 15) following the preceding pulse. The averaging (192, 205; 152, 165) of the sums (189; 149) of the squares (182, 187; 147, 142) of the orthogonal components is started leaving enough time for maximum deceleration at current speeds. Conflict in use of A/D (41) is resolved by registering the output (123; 124) in both channels. Square wave signals (23) are used for built-in test interleaved with signal processing. Non-integer pulses per revolution are accommodated with a counter (95) that counts modulo-one-bit-higher than a small integer multiple of a number close to the non-integer number.

Abstract: A device for generating synchronous numeric signals, including a reference generating device supplying a reference signal and a first timing signal, both having a reference frequency; and a timed generating device supplying a synchronized signal having the reference frequency. The device further includes a synchronization stage generating a second timing signal having a first controlled frequency correlated to the reference frequency, and phase synchronization pulses having the first frequency and a preset delay programmable with respect to the first timing signal.

Abstract: A resolver (20, 21) is provided with redundant excitation windings in which only a single excitation winding (E1) is energized externally. Cross coupling from the externally energized winding (E1) excites the other excitation winding (E2). A control circuit (27, 28) monitors the excitation of the redundant excitation winding (E2) and switches the excitation to the redundant excitation winding (E2) in the event of a failure of the externally winding (E1).

Abstract: A resolver system and method is provided for determining the angle position of a shaft. The resolver system includes a resolver having first and second output windings and an input or reference winding spaced apart from the first and second output windings, where either the input winding or the output windings are connected to the shaft. When a drive signal is introduced into the input winding, it generates first and second output signals on the output windings representing the angle position of the shaft. The resolver system of the present invention further includes a processor connected to the output windings for receiving the first and second data signals from the resolver and determining the angle position of the shaft. For generating the drive signal, the resolver system further includes a drive circuit connected to the input winding of the resolver. The drive circuit generates a pulsed drive signal for input into the resolver.

Abstract: It is an object of this invention to provide a digital conversion method for an analog signal in which, when sin(&thgr;−&phgr;) is calculated as a error deviation &egr;, a first output signal sin(&thgr;−&phgr;)·f(t) of the previous stage of the error deviation &egr; is converted into a digital signal by positive/negative sign determination performed by a comparator to make almost circuits into digital circuits, thereby making it easy to form an IC. In the digital conversion method for an analog signal according to the invention, sin(&thgr;−&phgr;)·f(t) obtained by guiding the rotation detection signal to a multiplier and operating the rotation detection signal is converted into a digital signal by positive/negative sign determination performed by a comparator to achieve a stable and inexpensive configuration.

Abstract: A method and system for calibrating analog integrated circuits. Initially, a single calibration circuit is formed integral with a group of analog integrated circuits. A control signal and a calibration signal are generated from the calibration circuit. Next, the control signal and the calibration signal are selectively coupled to an input of a particular analog integrated circuit among the group of analog integrated circuits. The particular analog integrated circuit is then selected for calibration via the control signal.

Abstract: The converter produces a linear analog signal that is linearly proportional to a shaft angle of a resolver over 360.degree.. An excitation cosine signal supplied to the resolver and a response cosine signal received from the output windings of the resolver are converted to logic level signals. Digital logic is performed on the logic level signals in a programmable digital logic device to produce a logic level pulse-width modulated signal. The logic level pulse-width modulated signal is used to control a switch to switch between two reference voltage levels to produce a pulse-width modulated signal, which is filtered and buffered to produce the linear analog signal.

Abstract: An advanced multi-channel synchro-to-digital converting device for deliveg synchro data to a data bus, includes a digital-to-synchro synthesizer for generating synthesized analog synchro test signals, and switching for selectively substituting the synthesized synchro signals for synchro signals, with the selection of conversion channels and the magnitudes of the synthesized analog synchro signals both under the control of data on the data bus.

Abstract: Output of an encoder are sampled by A/D converters 11a and 11b to be converted to N bits A-phase and B-phase digital data DA and DB. In a look-up table memory 12, reference phase angle data of phase divisions and average gradient vectors of changes in phase angle data within the phase divisions are stored, the phase divisions being addressed by the high order NU bits of data DA and DB. An arithmetic circuit 13 determines a vector inner product of an average gradient vector and phase-interpolating data represented by the low order NL bits of the data DA and DB to add the resultant to a phase angle data, thereby outputting an interpolated phase angle data.

Abstract: A software-based resolver-to-digital converter (RDC) (80) for computing an angle of rotation .THETA. of gimbal-mounted instrumentation (16) in a gimbal system. The RDC (80) computes the angle of rotation of the instrumentation using parameter signals received from a resolver (32) in the system. The parameter signals, along with a resolver reference signal are input into a multiplexor (60) and are multiplexed. The signals are then fed to an analog to digital converter (38) and converted to digital form. The digital signals are then input into a processor (36) associated with the system. This processor, in addition to performing numerous system computations, is programmed through appropriate software to filter the digital signals received, compute the value for the angle of rotation .THETA. and output the computed value to system circuitry (31) for processing to enhance system operation.

Abstract: A synchronization adder circuit for digital data communication includes an A/D converter, a waveform-shaping circuit, a square circuit, a low-pass filter, and an adder. The A/D converter samples at given sampling points in time per sampling cycle a received signal transmitted through a plurality of subcarriers to digitize sampled values to provide digital signals. The waveform-shaping circuit then waveform-shapes the digital signals from said A/D converter without decomposing them with respect to each subcarrier. The square circuit squares the output signals from the waveform-shaping circuit. The low-pass filter removes a given high-frequency component from output signals from the square circuit. The adder adds values of output signals from the low-pass filter at each sapling point for preselected sapling cycles to determine the samples suitable for reproduction of original data.

Abstract: An electrical system for converting a magnetic azimuth detector (MAD) signal into a corresponding digital signal. A conversion circuit receives a three-wire signal from the MAD; the three-wire signal is proportional to an angle .theta., which indicates the position of the MAD relative to magnetic north. The conversion circuit converts the three-wire signal into sin .theta. and cos .theta. signals. A digitization circuit converts the sin .theta. and cos .theta. signals into corresponding digital signals by first half-wave demodulating the analog sin .theta. and cos .theta. signals, then low-pass filtering the signals to extract the DC components, and finally digitizing the analog DC components.

Abstract: A software-based resolver-to-digital converter (RDC) (80) for computing an angle of rotation &THgr; of gimbal-mounted instrumentation (16) in a gimbal system. The RDC (80) computes the angle of rotation of the instrumentation using parameter signals received from a resolver (32) in the system. The parameter signals, along with a resolver reference signal are input into a multiplexor (60) and are multiplexed. The signals are then fed to an analog to digital converter (38) and converted to digital form. The digital signals are then input into a processor (36) associated with the system. This processor, in addition to performing numerous system computations, is programmed through appropriate software to filter the digital signals received, compute the value for the angle of rotation &THgr; and output the computed value to system circuitry (31) for processing to enhance system operation.