Serrasoid phase modulator

Claim 2

A serrasoid phase modulator, responsive to a modulation signal to develop a phase modulated carrier wave, including in combination: signal processing means adapted to receive the modulation signal and being responsive thereto to develop a pulse train signal of variable width pulses at a first conductor, each of said variable width pulses having a first edge with a fixed time relationship with the first edges of the other of said pulses in said pulse train and a second edge, said second edges having a variable time relationship with the first edges of said pulses; pre-emphasis means connected to said first conductor, said preemphasis means being responsive to said pulse train signal to pre-emphasize the high frequency components thereof to provide a pre-emphasized signal at a second conductor; de-emphasis means connected to said first conductor and being responsive to said pulse train signal to de-emphasize the high frequency components thereof to provide a de-emphasized signal at a third conductor; and comparator means connected to said second and third conductors for comparing the relative magnitudes of said pre-emphasized and de-emphasized signals, to develop therefrom a train of variable position output pulses having first edges substantially coincident with said second edges of said variable width pulses and second edges occurring at times determined by said relative magnitude of said de-emphasized and pre-emphasized signals.

Claim 3

The serrasoid phase modulator of claim 1 wherein, said second edge of each of said variable width pulses in said pulse train signal is the leading edge and said first edge of each of said variable width pulses in said pulse train signal is the trailing edge.

Claim 4

The serrasoid phase modulator of claim 1 further including, filter means coupled to said comparator means, said filter means being responsive to said variable position output pulse to filter the same and thereby attenuate all but one harmonic of said variable position output pulses.

Claim 5

The serrasoid phase modulator of claim 3 further including, bias circuit means coupled to said comparator means, said bias circuit means acting to apply a bias potential to said comparator means for changing said relative magnitudes of said de-emphasized and pre-emphasized signals.

Claim 6

A serrasoid phase modulator responsive to a modulation signal to develop a phase modulator carrier wave, including in combination: means for developing timed pulse signals; ramp generator means coupled to said means for developing timed pulse signals and being responsive to said timed pulse signals to develop ramp signals having a period equal to the period of said timed pulse signals; first comparator means coupled to said ramp generator means, said first comparator means being adapted to receive the modulation signal and to compare the amplitudes of the modulation signal and said ramp signal to dEvelop a first pulse train signal of variable width pulses at a first conductor, said variable width pulses having leading edges occurring in response to the relative amplitude of the modulation signal and said ramp signal; first pre-emphasis means coupled to said first conductor and being responsive to said first pulse train signal to pre-emphasize the high frequency components thereof to develop a first pre-emphasized signal whereby the leading edges of said pulses thereof have greater amplitudes than the trailing edges thereof; first de-emphasis means coupled to said first conductor and being responsive to said first pulse train signal to de-emphasize the high frequency components thereof to develop a first de-emphasized signal whereby the leading edges of said pulses thereof have lower amplitudes than the trailing edges thereof; second comparator means coupled to said first pre-emphasis means and to said first de-emphasis means and being responsive to said first pre-emphasized and first de-emphasized signals to develop a first output pulse signal having a first amplitude in response to the amplitude of said first preemphasized signal being greater than the amplitude of said first de-emphasized signal and a second amplitude in response to the amplitude of said first de-emphasized signal being greater than the amplitude of said first pre-emphasized signal, whereby said first output pulse signal has pulses with relative positions with respect to each other, said relative positions being dependent upon the modulation signal.

Claim 7

A serrasoid phase modulator responsive to a modulation signal to develop a phase modulator carrier wave, including in combination: means for developing timed pulse signals; ramp generator means coupled to said means for developing timed pulse signals and being responsive to said timed pulse signals to develop ramp signals having a period equal to the period of said timed pulse signals; first comparator means coupled to said ramp generator means, said first comparator means being adapted to receive the modulation signal and to compare the amplitudes of the modulation signal and said ramp signal to dEvelop a first pulse train signal of variable width pulses at a first conductor, said variable width pulses having leading edges occurring in response to the relative amplitude of the modulation signal and said ramp signal; first pre-emphasis means coupled to said first conductor and being responsive to said first pulse train signal to pre-emphasize the high frequency components thereof to develop a first pre-emphasized signal whereby the leading edges of said pulses thereof have greater amplitudes than the trailing edges thereof; first de-emphasis means coupled to said first conductor and being responsive to said first pulse train signal to de-emphasize the high frequency components thereof to develop a first de-emphasized signal whereby the leading edges of said pulses thereof have lower amplitudes than the trailing edges thereof; second comparator means coupled to said first pre-emphasis means and to said first de-emphasis means and being responsive to said first pre-emphasized and first de-emphasized signals to develop a first output pulse signal having a first amplitude in response to the amplitude of said first preemphasized signal being greater than the amplitude of said first de-emphasized signal and a second amplitude in response to the amplitude of said first de-emphasized signal being greater than the amplitude of said first pre-emphasized signal, whereby said first output pulse signal has pulses with relative positions with respect to each other, said relative positions being dependent upon the modulation signal.

Claim 8

The serrasoid phase modulator of claim 5 wherein: said second comparator means is a differential amplifier having a first state for developing said first amplitude of said first output pulse signal and a second state for developing said second amplitude of said first output pulse signal, said differential amplifier being responsive to said leading edge of said first pre-emphasized signal to be switched to said first state, said differential amplifier being responsive to a predetermined difference between the amplitudes of said first pre-emphasized and first de-emphasized signals to be switched to said second state; and bias circuit means coupled to said differential amplifier for applying a bias potential thereto whereby the relative amplitudes of said first pre-emphasized and said first de-emphasized signals are changed thereby changing the point at which said second differential amplifier is switched from said second state to said first state.

Claim 9

The serrasoid modulator of claim 5 wherein, said first pre-emphasis means and said first de-emphasis means each are formed by resistance-capacitance networks.

Claim 10

The serrasoid modulator of claim 5 wherein, said means for developing said timed pulse signals is a class C oscillator.

Claim 11

The serrasoid modulator of claim 5 further including: capacitance means coupled to said second comparator means for integrating said output pulse signal therefrom to develop a variable position ramp signal; third comparator means adapted to receive the modulation signal and coupled to said capacitance means, said third comparator means being responsive to the relative amplitudes of the modulation signal and said variable position ramp signal to develop a second pulse train signal of variable width pulses at a second conductor; second pre-emphasis means coupled to said second conductor and being responsive to said second pulse train signal of variable width pulses to de-emphasize the high frequency components thereof to develop a second pre-emphasized signal; second de-emphasis means coupled to said second conductor and being responsive to said second variable width pulse train signal to de-emphasize the high frequency components thereof to develop a second de-emphasized signal; fourth comparator means coupled to said second pre-emphasis means and said second de-emphasis means and being responsive to said second pre-emphasized and said second de-emphasized signals to develOp a second output pulse signal having a third amplitude in response to the magnitude of said second pre-emphasized signal being greater than the magnitude of said second de-emphasized signal and a fourth amplitude in response to the magnitude of said second de-emphasized signal being greater than the magnitude of said second pre-emphasized signal, whereby said second output pulse signal has pulses with relative positions with respect to each other dependent upon the modulation signal.

Claim 12

A serrasoid phase modulator which is responsive to a modulation signal to develop a modulated carrier wave, the modulator including in combination: signal processing means adapted to receive the modulation signal and being responsive to said modulating signal to develop a pulse train of variable width pulses at an output terminal thereof, each of said variable width pulses being comprised of high and low frequency components and having first and second edges, said first edges having magnitudes controlled by the magnitudes of said low frequency components and having fixed time intervals therebetween, said second edges having magnitudes controlled by the magnitudes of said high frequency components, and having time intervals therebetween which vary with the modulating signal; pre-emphasis means having an input terminal connected to said output terminal of said signal processing means and an output terminal, said pre-emphasis means increasing the magnitude of said high frequency components with respect to said magnitudes of said low frequency components to increase the magnitudes of said second edges of said variable width pulses with respect to the magnitudes of said first edges to provide a pre-emphasized signal at said output terminal thereof; de-emphasis means having an input terminal connected to said output terminal of said signal processing means and an output terminal, said de-emphasis means decreasing the magnitudes of said low frequency components to decrease the magnitudes of said second edges with respect to said first edges to provide a de-emphasized signal at said output terminal thereof; and comparator means having a first input terminal coupled to said output terminal of said pre-emphasis means and a second input terminal coupled to said output terminal of said de-emphasis means and an output terminal, said comparator means responding when the instantaneous magnitudes of said preemphasized signals exceed the corresponding instantaneous magnitudes of said de-emphasized signals to develop a train of variable position output pulses at said output terminal thereof.

Claim 13

A serrasoid phase modulator which is responsive to a modulation signal to develop a modulated carrier wave, the modulator including in combination: signal processing means adapted to receive the modulation signal and being responsive to said modulating signal to develop a pulse train of variable width pulses at an output terminal thereof, each of said variable width pulses being comprised of high and low frequency components and having first and second edges, said first edges having magnitudes controlled by the magnitudes of said low frequency components and having fixed time intervals therebetween, said second edges having magnitudes controlled by the magnitudes of said high frequency components, and having time intervals therebetween which vary with the modulating signal; pre-emphasis means having an input terminal connected to said output terminal of said signal processing means and an output terminal, said pre-emphasis means increasing the magnitude of said high frequency components with respect to said magnitudes of said low frequency components to increase the magnitudes of said second edges of said variable width pulses with respect to the magnitudes of said first edges to provide a pre-emphasized signal at said output terminal thereof; de-emphasis means having an input terminal connected to said output terminal of said signal processing means and an output terminal, said de-emphasis means decreasing the magnitudes of said low frequency components to decrease the magnitudes of said second edges with respect to said first edges to provide a de-emphasized signal at said output terminal thereof; and comparator means having a first input terminal coupled to said output terminal of said pre-emphasis means and a second input terminal coupled to said output terminal of said de-emphasis means and an output terminal, said comparator means responding when the instantaneous magnitudes of said preemphasized signals exceed the corresponding instantaneous magnitudes of said de-emphasized signals to develop a train of variable position output pulses at said output terminal thereof.