Process and a system for digital modulation

Claim 2

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 k , a sequence of switch-on and switch-off points t se , t sa and the positive or negative sign of each pulse within the sequence of pulses for the same sampling period Δt k .

Claim 3

A process according to claim 1, wherein for implementing of a pseudo-rate modulator, the switch-on points t se within a particular time interval Δt k are determined according to the following equation: ##EQU5## wherein e k is a sampled value of the input signal during a k-th time interval; h 1 is a switch-on threshold of a modulator hysteresis; T M is a time constant in a feedback branch of the modulator; r s-1 is an internal feedback signal of a preceding switch-off point t a ; and Δt sum is a cumulative sum of switch-on and switch-off intervals for a current time interval Δt k , in each case situated between switch-on and switch-off points, and between switch-off and switch-on points.

Claim 4

A process according to claim 2, wherein for implementing of a pseudo-rate modulator, the switch-off points t sa within a particular sampling period Δt k are determined according to the following equation: ##EQU6## wherein e k is a sampling value of the input signal during a k-th sampling period; h 2 is a switch-off threshold of a modulator hysteresis; T M is a time constant in a feedback branch of the modulator; r s-1 is an internal feedback signal of a preceding switch-on point t se ; K M is an amplification factor in said feedback branch; i s-1 is a preceding switching condition; and Δt sum is a cumulative sum of switch-on and switch-off intervals for a current sampling period Δt k , in each case situated between switch-on and switch-off points, and between switch-off and switch-on points.

Claim 5

A process according to claim 3, wherein the determination of the sequence of switch-on and switch-off points t se and t sa for a particular time interval Δt k is terminated when a cumulative sum At of all switch-on and switch-off intervals Δt se and Δt sa within the time interval Δt k exceeds known length of the time interval.

Claim 6

A process according to claim 1, wherein for implementing of a pseudo-rate modulator, the switch-off points t sa within a particular sampling period Δt k are determined according to the following equation: ##EQU7## wherein e k is a sampling value of the input signal during a k-th sampling period; h 2 is a switch-off threshold of a modulator hysteresis; T M is a time constant in a feedback branch of the modulator; r s-1 is an internal feedback signal of a preceding switch-on point t se ; K M is an amplification factor in said feedback branch; i s-1 is a preceding switching condition; and Δt sum is a cumulative sum of switch-on and switch-off intervals for a current sampling period Δt k , in each case situated between switch-on and switch-off points, and between switch-off and switch-on points.

Claim 7

A process according to claim 5, wherein the determination of the sequence of switch-on and switch-off points t se and t sa for a particular time interval Δt k is terminated when a cumulative sum Δt sum of all switch-on and switch-off intervals Δt se and Δt sa within the time interval Δt k exceeds known length of the time interval.

Claim 8

A process according to claim 1, wherein for implementing of a pseudo-rate modulator, the switch-on points t se within a particular sampling period Δt k are determined according to the following equation: ##EQU8## wherein e k is a sampling value of the input signal during a k-th sampling period; h 1 is a switch-on threshold of a modulator hysteresis; T M is a time constant in a feedback branch of the modulator; r s-1 is an internal feedback signal of a preceding switch-off point t sa ; and Δt sum is a cumulative sum of switch-on and switch-off intervals for a current sampling period At k , in each case situated between switch-on and switch-off points, and between switch-off and switch-on points.

Claim 9

A process according to claim 7, wherein for implementing of a pseudo-rate modulator, the switch-off points t sa within a particular sampling period Δt k are determined according to the following equation: ##EQU9## wherein K M is an amplification factor in the feedback branch of the modulator; i s-1 , preceding switching condition; and h 2 is a switch-off threshold of the modulator hysteresis.

Claim 10

A process according to claim 1, wherein for implementing of a pseudo-rate modulator, the switch-off points t sa within a particular sampling period Δt k are determined according to the following equation: ##EQU10## wherein e k is a sampling value of the input signal during a k-th sampling period; h 2 is a switch-off threshold of a modulator hysteresis; T M is a time constant in a feedback branch of the modulator; r s-1 is an internal feedback signal of a preceding switch-on point t se ; K M is an amplification factor in said feedback branch; i s-1 is a preceding switching condition; and Δt sum is a cumulative sum of switch-on and switch-off intervals for a current sampling period Δt k , in each case situated between switch-on and switch-off points, and between switch-off and switch-on points.

Claim 11

A process according to claim 1, wherein the determination of the sequence of switch-on and switch-off points t se and t sa for a particular time interval Δt k is terminated when a cumulative sum Δt sum of all switch-on and switch-off intervals Δt se and Δt sa within the time interval Δt k exceeds known length of the time interval.

Claim 12

A process according to claim 10, wherein a feedback signal r s assigned to an end point of a particular sampling period Δt k ending in a switched-off condition is generated according to one of the following equations: ##EQU11## wherein r s-1 , is an internal feedback signal of a preceding switch-on point; and T M is a time constant in a feedback branch of the modulator.

Claim 13

A process according to claim 10, wherein a feedback signal r s assigned to an end point of a particular sampling period Δt k ending in a switched-on condition is generated according to one of the following equations: ##EQU12## wherein, r s-1 is an internal feedback signal of a preceding switch-off point; T M is a time constant of a feedback branch of the modulator; i s-1 is a preceding switching condition; and K M is an amplification factor in said feedback branch.

Claim 14

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 Δt k , a sequence of switch-on and switch-off points, t se and t 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 Δt k .

Claim 15

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 Δt k , a sequence of switch-on and switch-off points, t se and t 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 Δt k .

Claim 16

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 Δt k , a sequence of switch-on and switch-off points, t se and t 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 Δt k .

Claim 17

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 Δt k , a sequence of switch-on and switch-off points, t se and t 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 Δt k .

Claim 18

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 se and t 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 Δt k .

Claim 19

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 se and t 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 Δt k .

Claim 20

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.

Claim 21

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.