Spread Spectrum Modulation Techniques PPTspead spectrum modulation technique
Fig. 7.Spread Spectrum Modulation 6.1.1Direct Sequence Spread Spectrum (DSSS) DSSSis the most fundamental form ofspread spectrumtechniques. In this type, the message or signal wave is spread by modulation using a wide band code known as the Pseudo Noise (PN) code. This PN code consists of...
Part 2 explains Phase Shift Keying (PSK) and Quadrature Amplitude Modulation (QAM). Spread spectrum techniques In many instances it is necessary to keep transmissions as narrow as possible to conserve the frequency spectrum. However, under some circumstances it is advantageous to use what are know...
Spread Spectrum Frequency Modulation Techniques Even though the periodic frequency modulation is effective in spreading the frequency spectrum of noises, we will focus our discussion on pseudo-random modulation. In this technique, the clock shifts from one frequency to another in a pseudo-random fashion...
Spread spectrum communication techniques for a code division message multiplexing systemOF THE DISCLOSUREA transmission system is described, suitable for transmitting\nmultiple messages over a single carrier. At the transmitter, a message-\nmodulated carrier is given an additional modulation by an ...
Chirp-rate modulation (CRM) is a kind of technique of spread spectrum which has the ability of anti-multipath and anti-interception. Meanwhile as a modulat... D Bing,T Ran,E Chen 被引量: 7发表: 2006年 Alternative Chirp Spread Spectrum Techniques for LPWANs Wireless communicationChirp spread...
spreadspectrummodulation 系统标签: spreadspectrummodulationsequencespreadingsignal Chapter7 SpreadSpectrumModulation 7.1Introduction Inthetechniqueofspreadspectrum,thefrequencyspectrumofadata-signal(shaded inFig.7.1)isspread(non-shaded)usingacodeuncorrelatedwiththatsignal.Asa resultthebandwidthoccupancyismuchhigherthanreq...
SpreadSpectrum 1 Definition Spreadspectrumtechniquesspreadinformationoveraverylargebandwidth–specifically,aband-widththatismuchlarger thantheinverseofthedatarate.2 Origins “spreadspectrum”comesfromthemilitaryarea,wherethemain interestliesinkeepingcommunicationsstealthy,safefromintercept,andsafefromjammingeffortsby...
Spread-spectrum modulation techniques have been adopted for many current and future military communication systems to accommodate high data rates with high... MM Olama,X Ma,PT Kuruganti,... 被引量: 11发表: 2011年 Bounds on the number of users in spread-spectrum systems Upper bounds on the nu...
Spread-spectrum modulation techniques have been adopted for many current and future military communication systems to accommodate high data rates with high... MM Olama,X Ma,PT Kuruganti,... 被引量: 11发表: 2011年 Data transmission within a spread-spectrum communication system Rate assignment circuit...