US 4,109,101 A · Correlative converter between a 2.sup.n -ary code sequence and a 2.sup.n+1 -phase carrier pulse sequence

Abstract

A novel modulator converts a sequence of N'ary codes representative of an element P of a set (0, 1, 2, . . . , N - 1) into a sequence of 2N-phase carrier pulses, where N = 2.sup.n, n being a positive integer. A phase shift in the carrier signal between each carrier pulse and the next preceding one is selected from P.pi./N and (P + N).pi./N in compliance with a prescribed law of correlation between the N'ary codes in the sequence. Alternatively, the carrier signal is given in each carrier pulse a phase selected in the manner specified. For convenience of resorting to the prescribed correlation law, the N'ary code sequence may be converted into N trains, corresponding to the respective elements P, of three-level signals, 0 and .+-.1. In the train corresponding to a particular element, the three-level signals are successively produced with the prescribed correlation law, such as with resort to a bipolar or duobinary technique. A novel demodulator converts the 2N-phase carrier pulse sequence into the original N'ary code sequence.

Claims10

Dependent claims

A correlative phase modulator for converting a binary information signal into an eight phase psk signal, said correlative phase modulator comprising:

first encoder means responsive to said binary information signal for generating one of four possible quaternary signals during each of a plurality of successive time periods, the particular one of said four possible quaternary signals generated during each of said time periods being determined by said binary information signal;
second encoder means responsive to said quaternary signals for generating one of eight possible octernary signals during each of said time periods, the particular one of said eight possible octernary signals generated during any given one of said time periods being determined by a predetermined law of correlation between the quaternary signals generated during two successive time periods, said second encoder means generating said octernary signals in such a manner that any of the eight possible octernary signals may be generated during each of said time periods;
eight phase modulator means responsive to said octernary signals for eight-phase modulating a carrier signal as a function of said octernary signals.

A correlative phase modulator for converting a binary information signal into a 5-phase psk signal, comprising:

first encoder means responsive to said binary information signal for generating one of four possible quarternary signals during each of a plurality of time periods, the particular one of said four possible quarternary signals generated during each of said time periods being determined by said binary information signal.
second encoder means responsive to said quarternary signals for generating one of five possible octernary signals during each of said time periods, the particular one of said five possible octernary signals generated during any given one of said time periods being determined by a predetermined law of correlation between the octernary signals generated during two successive time periods, said second encoder means generating said octernary signals in such a manner that any one of the five possible octernary signals may be generated during each of said time periods;
and
phase modulator means responsive to said octernary signals for 8-phase modulating a carrier signal as a function of said octernary signals.

1 more element

Dependencies are inferred from the claim text.

Correlative converter between a 2.sup.n -ary code sequence and a 2.sup.n+1 -phase carrier pulse sequence

Life of this patent

Correlative converter between a 2.sup.n -ary code sequence and a 2.sup.n+1 -phase carrier pulse sequence

Life of this patent

Abstract

Claims10