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Spread spectrum modulation

Spread spectrum modulation 

Definition: 
                  "Spread spectrum modulation is a technique in which a communication signal is transmitted on a bandwidth considerably larger than the frequency content of the original information. Frequency hopping is a basic modulation technique used in spread spectrum signal transmission".

Spread spectrum modulation

Spread  spectrum  modulation 



















S S Mdulation Techniques





S S Mdulation Techniques

S S Mdulation Techniques



Applications of spread spectrum modulation




   
•       Applications of DS-SS system
Applications of DS-SS system
Applications of DS-SS system






















FH-MFSK receiver:
FH-MFSK receiver
FH-MFSK receiver




Frequency hop spread M-ary FSK transmitter

Frequency hop spread M-ary FSK transmitter



DSSS Coherent Binary Phase-Shift Keying  Receiver



 







 Frequency hop spread M-ary FSK transmitter

Magnified waveform for the period of 1st cycle



PSEUDO-NOISE (P-N) sequences 
Spread spectrum signal m(t)=b(t).c(t)



maximum length sequence generator

- model of spread spectrum digital communication system 
waveform of DS-SS transmitter  













DSSS Coherent Binary Phase-Shift Keying Transmitter























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