B. P. Lathi, Zhi Ding - Modern Digital and Analog Communication Systems-Oxford University Press (2009)

title ('second demodulator output ');
subplot (224) ;td8=plot (t,s_rec2) ;
axis ( Trange ); set (td8 , 'Linewidth ' , 1.5) ;
xlabel ('{\ it t } (sec ) '); ylabel ('{\it m}_ {d2 }({\it t } )')
title ('detected signal 2');
Frange= [-700 700 0 250] ;
figure (3)
subplot (221) ; fdl=plot (freqm, abs (Ml_fre) );
axis ( Frange ) ; set (fdl , 'Linewidth ' ,1.5) ;
xlabel ('{\it f} (Hz) '); ylabel ('{\it M} ({\it f}) ');
title ('message 1 spectrum' );
subplot (222) ;fd2=plot ( freqs ,abs (S_qam) );
axis ( Frange ) ; set (fd2 , 'Linewidth ' , 1.5) ;
xlabel ('{\it f} (Hz) '); ylabel ('{\ it S } _{rm AM} ({\it f}) ');
title ('QAM spectrum magnitude ');
subplot (223) ;fd3=plot ( freqs ,abs (S_deml ) ) ;
axis ( Frange ) ; set (fd3 , 'Linewidth ' ,1.5) ;
xlabel ('{\it f } (Hz) ' } ; ylabel ('{\it E}_l({\it f } )');
title ('first demodulator spectrum' );
subplot (224) ;fd4=plot ( freqs ,abs (S_recl) );
axis ( Frange ); set (fd4 , 'Linewidth ' ,1.5);
xlabel ('{\it f } (Hz) ' ) ; ylabel ('{\it M}_{dl }({\it f})');
title ('recovered spectrum 1');
figure (4)
subplot (221) ;fdl=plot (freqm, abs (M2_fre) );
axis ( Frange ) ; set (fdl , 'Linewidth ' ,1.5) ;
xlabel ('{\it f } (Hz) '); ylabel ('{\it M} ({\ it f}) ');
title ('message 2 spectrum' );
subplot (222) ;fd2=plot ( freqs ,abs (S_qam) ) ;
axis ( Frange ) ; set (fd2 , 'Linewidth ' ,1.5) ;
xlabel ('{\it f} (Hz ) '); ylabel ('{\it S}_ {rm AM} ({\ it f})');
title ('QAM spectrum magnitude '};
subplot (22 3) ; fd7=plot (freqs,abs (S_dem2 ) );
axis ( Frange ) ; set (fd7 , 'Linewidth ' ,1.5) ;
xlabel ('{\it f} (Hz ) ' ) ; ylabel ('{\it E } _2 ({\ it f})');
title ('second demodulator spectrum' );
subplot (224) ; fd8=plot (freqs , abs (S_rec2 ));
axis ( Frange ) ; set (fd8 , 'Linewidth ' ,1.5) ;
xlabel ('{\it f} (Hz) '); ylabel ('{\it M } _ { d2 } ({\ it f})');
title ('recovered spectrum 2');
References 195
REFERENCES
1. Single Sideband Issue, Proc. IRE, vol. 44, Dec. 1956.
2. D. K. Weaver Jr., "A Third Method of Generation and Detection of Single Sideband Signals," Proc.
IRE, vol. 44, pp. 1703-1705, Dec. 1956.
3. Bell Telephone Laboratories, Transmission Systems fo r Communication, 4th ed., Murray Hill, NJ,
1970.