Patent
Combined coherent frequency and phase shift keying modulation system
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TLDR
In this article, a system of modulation and demodulation for the transmission of binary data in the presence of multipath was proposed, where the binary data modulates the phase of the carrier and the same binary data, after a delay of "δ" bits, also modifies the frequency of the operator.Abstract:
A system of modulation and demodulation for the transmission of binary data in the presence of multipath. The binary data modulates the phase of the carrier and the same binary data, after a delay of "δ" bits, also modulates the frequency of the carrier. Following reception, the binary data is obtained either by frequency demodulation or by a method of coherent phase shift demodulation wherein the mark or the space frequency is selected for detection of each bit in accord with the bit received "n" bits previously. The system selects between the demodulation methods to obtain one which operates satisfactorily in the instant electromagnetic environment.read more
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Patent
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TL;DR: In this article, a method and apparatus for generating phase and amplitude modulated signals to be transmitted and for demodulating the transmitted signals with improved reliability and accuracy is disclosed, where a modulator at the transmitter is adapted to continuously group digital data into multibit words of equal length.
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