Patent
Spread spectrum communications system
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TLDR
In this paper, a spread spectrum communications system with a modulator and a pseudonoise clock is described, where the pseudoneoise signal is generated synchronously with the transmit signal to reproduce the input signal.Abstract:
A spread spectrum communications system includes: a transmitter having an input information a modulator for generating a spread spectrum signal in accordance with an input information signal together with a pseudonoise clock signal used to generate a first pseudonoise signal formed of a plurality of chips, a switch for switching on and off a locally generated carrier signal of said input information signal in accordance with the spread spectrum signal, a first means for inverting a phase of the spread spectrum signal when the value of the pseudonoise signal is equal to one, a second means for multiplying the inverted-phase spread spectrum signal by the carrier signal so as to produce a transmit signal at an output of the second means, and an output means for outputting the transmit signal from the second means so that the transmit signal is transmitted from the transmitter; and a receiver which receives the transmit signal from the transmitter, the receiver having a detector for obtaining a baseband signal from the transmit signal received at the detector, and a demodulation part for demodulating the baseband signal with a second pseudonoise signal which is generated synchronously with the transmit signal, so as to reproduce the input information signal.read more
Citations
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References
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Patent
Spread spectrum modulating device
Endo Mamoru,Yoshitaka Uchida +1 more
TL;DR: In this paper, a simple and small scale construction can be realized for the spread spectrum modulating device, where parallel data outputted by the memory are converted into analogue signals by a D/A converter, which analogue signals are multiplied by a carrier by a multiplier to obtain a spread spectrum signal.
Patent
Spread-spectrum multiplexed transmission system.
TL;DR: In this paper, a spread-spectrum transmission system is proposed, where a plurality of spread spectrum signals are frequency division multiplexed by offsetting the center or carrier frequencies of the spread-Spectrum signals by a fraction of the spectral-line spacing of the signals.
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Method and apparatus for increasing the data rate for a given symbol rate in a spread spectrum system
TL;DR: In this paper, a method and apparatus for transmitting a stream of data bits in a spread spectrum format is disclosed, which comprises providing 2 N predetermined spreading sequences, where N is equal to or larger than 2.
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Spread spectrum communications with resistance to multipath at differential delays both larger and smaller than a chip width
TL;DR: In this article, the authors describe a spread spectrum communications system resistant to multipath due to differential delays equal to or less than a chip width, where at the transmitter, a pseudonoise sequence is combined with data for transmission purposes and the result of that combining operation is then encoded.
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TL;DR: In this paper, a spread spectrum communication (SSC) receiving device is disclosed, in which a received signal consisting of an SSC signal in the SC signal band and disturbance wave is divided into an upper side band and a lower side band.