Process and a system for digital modulation
AssigneeDeutsche Aerospace AG
InventorsHorst-Dieter Fischer, Helmut Bittner
Life of this patent
Estimating the term…
Abstract
A digital modulation process and apparatus for converting an input signal comprising a time variable series of sampling values, each of which sampling values remains constant within a fixed sampling period, into output signals representing a sequence of positive and/or negative pulses having a constant amplitude and a variable pulse width and frequency. The input signal and modulator parameters are supplied to a data processor. In order to reduce computing expenditures and at the same time achieve an increase in precision, by means of the computing system, the switch-on and switch-off points in time t.sub.se, t.sub.sa of the pulses as well as their operational signs are computed in one operation directly for each sampling period .DELTA.t.sub.k.
Claims16
A digital modulation process for converting an input signal comprising a time variable series of sampling values, each of which sampling values remains constant within a fixed constant sampling period, into output signals representing for each sampling period a sequence of pulses having a constant amplitude and a variable pulse width and frequency, said process comprising the steps of:
- entering the input signal into a data processor;
- entering modulator parameter values into said data processor;
- processing said input signal and said modulator parameter values in said data processor to determine, directly in a single operating cycle at the beginning of each sampling period t.sub.k, a sequence of switch-on and switch-off points t.sub.se, t.sub.sa and the positive or negative sign of each pulse within the sequence of pulses for the same sampling period .DELTA.t.sub.k.
A digital modulator for converting an input signal comprising a time variable series of sampling values, each of which sampling values remains constant within a fixed constant sampling period, into output signals representing for each sampling period a sequence of pulses having a constant amplitude and a variable pulse width and pulse frequency, said modulator comprising:
- a data processor;
- means for inputting desired modulator parameter values into said data processor;
- means for inputting said input signal into said data processor;
- said data processor comprising means for processing said input signals and said modulator parameter values and for determining, directly in a single operating cycle at the beginning of each sampling period .DELTA.t.sub.k, a sequence of switch-on and switch-off points, t.sub.se and t.sub.sa respectively, for said output sequence of pulses;
- and
- said data processor further comprising means for determining an operating sign for each of said switch-on points;
- said determination of switch-on and switch-off points and said determining of operating signs being performed directly in one single operating cycle for each sampling period .DELTA.t.sub.k.
A digital modulator for generating output signals representing a sequence of pulses of a constant amplitude and variable pulse width and frequency for the control of discretely operating control elements which operate on a controlled system as a function of an input signal which comprises a time-variable series of fixed constant sampling values, each of which sampling values remains constant during a fixed sampling period, and which input signal is indicative of a deviation of the controlled system from predetermined parameters, said modulator, comprising:
- a data processor having arithmetic units, memories, comparators and means for receiving modulator parameters and said input signal;
- said data processor comprising means for processing said input signals and said modulator parameter values and for determining, directly in a single operating cycle at the beginning of each sampling period .DELTA.t.sub.k, a sequence of switch-on and switch-off points, t.sub.se and t.sub.sa respectively, for said output sequence of pulses;
- and
- said data processor further comprising means for determining an operating sign for each of said switch-on points;
- said determination of switch-on and switch-off points and said determining of operating signs being performed directly in one single operating cycle for each sampling period .DELTA.t.sub.k.
A control arrangement comprising:
- at least one measuring unit for determining actual values of at least one controlled variable;
- a controller for determining deviation of said at least one controlled variable from a predeterminable desired value and for generating error signals comprising a time variable series of sampling values, each of which sampling values remains constant during a fixed sampling period;
- a digital modulator which receives the error signals as input signals and generates output signals representing a sequence of pulses of a constant amplitude and a variable pulse width and frequency;
- and
- at least one control device which is controlled by output signals of the digital modulator and acts upon a controlled system for influencing said at least one controlled variable, by emitting discrete control pulses;
- wherein said digital modulator has:
- means for receiving desired modulator operating parameters;
- means for receiving said input signal;
- means for processing said input signal and said modulator parameters and for determining a sequence of switch-on and switch-off points, t.sub.se and t.sub.sa respectively, for said output sequence of pulses;
- and
- means for determining an operating sign for each of said switch-on points;
- said determination of switch-on and switch-off points and said determining of operating signs being performed directly in one single operation for each sampling period .DELTA.t.sub.k.
A digital modulation process for converting an input signal comprising a time variable series of sampling values, each of which sampling values remains constant within a fixed sampling period, into output signals representing a sequence of pulses having a constant amplitude and a variable pulse width and frequency, said process comprising the steps of:
- first, processing said input signal in a data processor to determine a series of switch-on and switch-off signals indicative of switch-on and switch-off points of said output sequence of pulses;
- second, determining an operating sign for pulses in said output signal for each of said switch-on points;
- and
- third, outputting said sequence of pulses having respective switch-on and switch-off times and operating signs according to results of said first and second steps;
- wherein said first and second steps are performed directly in one single operation.
Dependencies are inferred from the claim text.