Modulators – Amplitude modulator – Nonlinear device controlled by modulating signal
Patent
1980-10-24
1983-11-22
Grimm, Siegfried H.
Modulators
Amplitude modulator
Nonlinear device controlled by modulating signal
332 21, 332 23R, 375 52, 375 53, 375 67, H03K 706, H04L 2720
Patent
active
044172192
ABSTRACT:
A phase shift binary modulator which is less sensitive to the non-linear characteristics of the transmission channel. The modulator comprises a first input to which a succession of binary bits are applied, prior to their modulation and transmission. Another input receives a clock signal at the bit rate of the succession of bits applied to the first input terminal, which is, in turn, connected to an input of a first exclusive OR gate, the output of which is connected to an input of another exclusive OR gate. The output of the other OR gate is connected to the input of a flip-flop. An output of the flip-flop is connected to the second input of the first OR gate. The clock signal drives a divider, the inverse output of which is connected to the second input of the other OR gate. The direct output of the divider is connected to an input of an AND gate. The second input of the AND gate is connected to the output of a delay circuit. The binary modulator may have either four or eight phase-shift displacements. In the four shift embodiment the binary symbol "1" is transmitted by a phase shift of +.pi./2, and the binary symbol "0" is transmitted by the phase-shift of -.pi./2. In the eight shift embodiment, the binary symbol "1" is transmitted by two successive shifts of +.pi./4, and the binary symbol "0" is transmitted by two successive shifts of -.pi./4. The successive shifts of + or -.pi./4 are performed at a clock rate which is double the numerical rate of delivery of the modulating binary signal.
REFERENCES:
patent: 3750051 (1973-07-01), Brady
patent: 4168397 (1979-09-01), Bradley
patent: 4174505 (1979-11-01), Querry
patent: 4210879 (1980-07-01), Poitevin et al.
Giannini et al., "Pulsed Offset QPSK Modulator", IBM Technical Disclosure Bulletin, vol. 21, Jun. 1978, pp. 123-124.
Brossard Pierre
Duponteil Daniel
LandOfFree
Phase displacement modulator does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Phase displacement modulator, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Phase displacement modulator will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1817301