Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
91 words
A process for generating a duo-binary FSK modulation comprising the steps of: first applying to a modulating binary signal train a 3- state partial response precoding, second applying to the precoded signal a coding by transition, third applying to the resulting transition coded signal a simplified MSK modulation at the carrier frequency, fourth dividing by two the modulated signal of the first step, and fifth applying to the modulated signal divided by two, a multiplication by the same modulated signal with a divided frequency delayed by one period of binary element.
Claim 2
Dependent Claim
91 words
A process for generating a duo-binary FSK modulation comprising the steps of: first applying to a modulating binary signal train a 3- state partial response precoding, second applying to the precoded signal a coding by transition, third applying to the resulting transition coded signal a simplified MSK modulation at the carrier frequency, fourth dividing by two the modulated signal of the first step, and fifth applying to the modulated signal divided by two, a multiplication by the same modulated signal with a divided frequency delayed by one period of binary element.
Claim 3
Dependent Claim
107 words
A process for generating a "tamed FSK" modulation, comprising the steps of: first applying to a modulating binary signal train a 3-state partial response precoding, second applying to the precoded signal a transition-type coding, third applying to the resulting transition coded signal a simplified MSK modulation at the carrier frequency, fourth dividing by two the signal modulated in the third step and fifth applying to the modulated signal divided by two a multiplication by the modulated signal with a frequency divided by two and delayed for one part by one period of a binary element and, for the other part, by two periods of said binary elements.
Claim 4
Dependent Claim
107 words
A process for generating a "tamed FSK" modulation, comprising the steps of: first applying to a modulating binary signal train a 3-state partial response precoding, second applying to the precoded signal a transition-type coding, third applying to the resulting transition coded signal a simplified MSK modulation at the carrier frequency, fourth dividing by two the signal modulated in the third step and fifth applying to the modulated signal divided by two a multiplication by the modulated signal with a frequency divided by two and delayed for one part by one period of a binary element and, for the other part, by two periods of said binary elements.
Claim 5
Dependent Claim
39 words
The process for generating a TFM modoulation, using the duo-binary FSK generating process according to claim 1, and the further step of wave shaping and filtering signals between the fourth division by two step and the fifth multiplication step.
Claim 6
Dependent Claim
156 words
A modulator which utilizes the process according to claim 1, said modulating comprising precoding circuit means, a transition-type coding circuit means, MSK modulator means, divide by two means, multiplier means, and delay-type circuit means, in which the modulating binary signal train is applied with partial response to said precoding circuit means, an output of which is connected to said transition-type coding circuit means, applying an output of said transition-type coding circuit means to the input of said simplified MSK modulator means, an output of said MSK modulator means being connected to the input of said means for dividing the frequency by two, an output of said divide by two means being connected for one part directly to the input of said multiplier means and, for the other part, to the other input of said multiplier means via said delay-type circuit means, in which the delay is equal to the period of the train of binary elements.
Claim 7
Dependent Claim
71 words
The modulator according to claim 4, to obtain a TFM modulation, and a wave shaping filter means, in which an output of said means for dividing by two is connected to the input of said wave shaping filter means the output of said wave shaping filter means being connected, for one part to an input of said multiplier and for the other part to the input of said delay-type circuit means.
Claim 8
Dependent Claim
43 words
The modulator according to claim 5, characterized in that the wave shaping filter means has a null impulse response when a delay time of a signal from said divider means by two is greater than the delay time of said delay-type circuit means.
Claim 9
Dependent Claim
31 words
A modulator according to claim 5, characterized in that said wave shaping filter means is a gaussian filter with three terminals and with a 3 dB band width equal to 0.7/T.