System and method for communicating data using constant amplitude waveform with hybrid orthogonal and MSK or GMSK modulation
AssigneeHarris Corporation
InventorsWilliam N. Furman, John W. Nieto, Michael A. Wadsworth
Life of this patent
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Abstract
A communications system of the present invention includes a transmitter that is operative for combining an orthogonal Walsh modulation with a minimum shift keying or Gaussian minimum shift keying waveform to form a hybrid communications signal that carries communications data over a constant amplitude waveform that is spread in time and frequency. This communications signal can be transmitted to a RAKE receiver that has a plurality of correlators with output weights formed for processing this hybrid communications signal.
Claims24
A system for communicating data, which comprises:
- an encoder and interleaver circuit for encoding and interleaving communications data to be transmitted with a forward error correction code and an orthogonal code to form a communications signal;
- a spread spectrum (SS) orthogonal or pseudo-orthogonal modulator for receiving the communications signal and forming a SS orthogonally or pseudo-orthogonally modulated and randomized sequence;
- and
- a modulator circuit for modulating a Gaussian minimum shift keying waveform with the SS orthogonally modulated and randomized sequence using a specific mapping algorithm and at least one of an (a) increased symbol rate and (b) inserted fixed symbols to form a communications signal having a constant amplitude waveform that is spread in time and frequency.
A system for communicating data, which comprises:
- a transmitter for transmitting a communications signal that carries communications data, and including a convolutional encoder for encoding the communications data with a forward error correction code, an interleaver, and an orthogonal encoder for encoding the communications data from the convolutional encoder with an orthogonal code to form encoded communications data;
- an orthogonal or pseudo-orthogonal modulator for receiving the encoded communications data and a binary randomizing sequence and forming an orthogonally or pseudo-orthogonally modulated, randomized and spread sequence;
- a modulator circuit for modulating a Gaussian minimum shift keying waveform with the orthogonally or pseudo-orthogonally modulated, randomized and spread sequence using a specific mapping algorithm and at least one of an (a) increased symbol rate and (b) inserted fixed symbols to form a communications signal having a constant amplitude waveform that is spread in time and frequency;
- and
- a RAKE receiver for receiving the communications signal from the transmitter, and including a plurality of correlators and output weights formed for processing the communications signal.
A method of communicating data, which comprises:
- modulating communications data to be transmitted by combining an orthogonal Walsh modulation with a Gaussian minimum shift keying waveform using a specific mapping algorithm and at least one of an (a) increased symbol rate and (b) inserted fixed symbols to form a communications signal that carries the communications data over a constant amplitude waveform that is spread in time and frequency;
- and
- transmitting the communications signal to a receiver.
A method of communicating data, which comprises:
- encoding communications data with forward error correction and orthogonal codes;
- combining a specific Walsh function with a binary randomizing sequence to form an orthogonally modulated, randomized and spread sequence of the communications data;
- modulating a Gaussian minimum shift keying waveform with the orthogonally modulated, randomized and spread sequence using a specific mapping algorithm and at least one of an (a) increased symbol rate and (b) inserted fixed symbols to form a communications signal that carries the communications data over a constant amplitude waveform that is spread in time and frequency;
- and
- transmitting the communications signal to a receiver.
Dependencies are inferred from the claim text.