Multi-level modulator for coherent phase-shift keyed signal generation

Claim 2

A modulator for encoding the information states carried via two binary signals, which are synchronized to a clock signal, into the phase deviations of a multi-level frequency modulated coherent phase-shift keyed signal comprising: means responsive to one of said binary signals for generating a first frequency modulated coherent phase-shift keyed signal having two phase deviations corresponding to the binary states of said one signal; means responsive to the other of said binary signals for generating a second frequency modulated coherent phase-shift keyed signal having two other different phase deviations corresponding to the binary states of said other signal; and means for mixing said first and second signals thereby producing an output signal comprising a frequency modulated coherent phase-shift keyed signal having four phase deviations.

Claim 3

A modulator in accordance with claim 1 in which said output signal is at the sum frequency of said first and second signals and said four phase deviations correspond, respectively, to the sum of each of said two phase deviations of said first signal with each of said two other different phase deviations of said second signal.

Claim 4

A modulator in accordance with claim 1 in which said output signal is at the difference frequency of said first and second signals and said four phase deviations correspond, respectively, to the difference of each of said two phase deviations of said first signal from each of said two other different phase deviations of said second signal.

Claim 5

A modulator in accordance with claim 1 in which said first signal has phase deviations of + or - pi /4 relative to a reference signal at its center frequency and said second signal has phase deviations of + or - pi /2 relative to a reference signal at its center frequency.

Claim 6

A modulator in accordance with claim 1 in which said means for generating said first phase-shift keyed signal comprises: a first binary modulator responsive to said one signal for developing a frequency modulated coherent phase-shift keyed signal having first and second phase deviations corresponding to the binary states of said one signal; and phase deviation converter means for receiving the phase shift-keyed signal from said first modulator and converting it into a frequency modulated coherent phase-shift keyed signal having third and fourth phase deviations: and said means for generating said second phase-shift keyed signal comprises: a second binary modulator responsive to said other signal for developing a frequency modulated coherent phase-shift keyed signal having two phase deviations corresponding to the binary states of said other signal which are the same as said first and second phase deviations.

Claim 7

A modulator in accordance with claim 5 in which said phase-shift keyed signals developed by said first and second modulators have the same center frequency.

Claim 8

A modulator in accordance with claim 6 in which said first phase deviation is + or - pi /2 and said second phase deviation is - pi /2 relative to a reference signal at said center frequency.

Claim 9

A modulator in accordance with claim 5 in which said phase deviation converter comprises a frequency divider circuit for performing a frequency and phase division of the phase-shift keyed signal developed by said first modulator.

Claim 10

A modulator for encoding the information states carried via a plurality of binary signals, which are synchronized to a clock signal, into the phase deviations of a multi-level frequency modulated coherent phase-shift keyed signal comprising: a plurality of successive signal paths each responsive to one of said binary signals, said plurality of paths including a first path, intermediate paths, and a last path; said first path comprising: a binary modulator for developing a first frequency modulated coherent phase-shift keyed signal having a center frequency fc and first and second phase deviations relative to said center frequency; and divider means for dividing the phase and frequency said first signal to produce a divided frequency output signal; said intermediate paths each comprising: a binary modulator for developing an intermediate, frequency modulated coherent phase-shift keyed signal having the same center frequency and phase deviations as said first signal; means for mixing said intermediate signal with the divided frequency output signal of the next preceding signal path to produce a mixed output signal; and divider means for dividing the phase and frequency of said mixed output signal to produce a divided frequency output signal; and said last of said plurality of paths comprising: a binary modulator for developing a last frequency modulated coherent phase-shift keyed signal having the same center frequency and phase deviations as said first and intermediate signals; and means for mixing said last signal with the divided frequency output signal of the next to last signal path to produce said multi-level frequency modulated coherent phase-shift keyed signal.

Claim 11

A modulator for encoding the information states carried via a plurality of binary signals, which are synchronized to a clock signal, into the phase deviations of a multi-level frequency modulated coherent phase-shift keyed signal comprising: a plurality of successive signal paths each responsive to one of said binary signals, said plurality of paths including a first path, intermediate paths, and a last path; said first path comprising: a binary modulator for developing a first frequency modulated coherent phase-shift keyed signal having a center frequency fc and first and second phase deviations relative to said center frequency; and divider means for dividing the phase and frequency said first signal to produce a divided frequency output signal; said intermediate paths each comprising: a binary modulator for developing an intermediate, frequency modulated coherent phase-shift keyed signal having the same center frequency and phase deviations as said first signal; means for mixing said intermediate signal with the divided frequency output signal of the next preceding signal path to produce a mixed output signal; and divider means for dividing the phase and frequency of said mixed output signal to produce a divided frequency output signal; and said last of said plurality of paths comprising: a binary modulator for developing a last frequency modulated coherent phase-shift keyed signal having the same center frequency and phase deviations as said first and intermediate signals; and means for mixing said last signal with the divided frequency output signal of the next to last signal path to produce said multi-level frequency modulated coherent phase-shift keyed signal.

Claim 12

A binary modulator in accordance with claim 9 in which said first and second phase deviations are + or - pi /2, respectively, and each of said divider means divides the frequency and phase of signals applied thereto by 2.

Claim 13

A modulator for encoding the information states carried via two or more information signals into the phase deviations of one frequency modulated coherent phase-shift keyed signal comprising: a first modulator means responsive to one or more of said information signals for developing a first frequency modulated coherent phase-shift keyed signal having phase deviations corresponding to the information states carried via said one or more information signals; a second modulator means responsive to the other remaining ones of said information signals for developing a second frequency modulated coherent phase-shift keyed signal having phase deviations corresponding to the information states carried via said remaining ones of said information signals; and means for mixing said first and second signals to produce said one frequency modulated coherent phase-shift keyed signal.

Claim 14

A modulator for encoding the information states carried via two or more information signals into the phase deviations of one frequency modulated coherent phase-shift keyed signal comprising: a first modulator means responsive to one or more of said information signals for developing a first frequency modulated coherent phase-shift keyed signal having phase deviations corresponding to the information states carried via said one or more information signals; a second modulator means responsive to the other remaining ones of said information signals for developing a second frequency modulated coherent phase-shift keyed signal having phase deviations corresponding to the information states carried via said remaining ones of said information signals; and means for mixing said first and second signals to produce said one frequency modulated coherent phase-shift keyed signal.

Claim 15

A modulator in accordance with claim 11 in which said one frequency modulated coherent phase-shift keyed signal is at the sum frequency of said first and second signals.

Claim 16

A modulator in accordance with claim 11 in which said second frequency modulated coherent phase-shift keyed signal has two phase deviations.