0195136047.pdf

634 SIGNAL PROCESSING Hence, the givenx(t) is a power-type signal with its power given byA^2 /2. (b) For any periodic signal wit ...

14.1 SIGNALS AND SPECTRAL ANALYSIS 635 EXAMPLE 14.1.4 Consider the following periodic waveforms shown in Figure E14.1.4: A t −T ...

636 SIGNAL PROCESSING (a) Rectangular pulse train (b) Triangular wave (c) Sawtooth wave (d) Square wave (e) Half-rectified sine ...

14.1 SIGNALS AND SPECTRAL ANALYSIS 637 An an bn φn Figure 14.1.3Phasor diagram of Fourier coefficients. EXAMPLE 14.1.5 The recta ...

638 SIGNAL PROCESSING A t (a) (b) AD −D/2 D/2 1/D 2/D 3/D f 0 Amplitude Figure 14.1.4Nonperiodic signal and its spectrum.(a)Sing ...

14.1 SIGNALS AND SPECTRAL ANALYSIS 639 Figure 14.1.5 shows a block diagram in which an arbitrary linear network characterized by ...

640 SIGNAL PROCESSING f 0 W Amplitude spectrum f 0 B H(f) K f θ(f) − 360 °td 0 Figure 14.1.6Frequency-domain interpretation of d ...

14.2 MODULATION, SAMPLING, AND MULTIPLEXING 641 signal needs to besampledas part of the modulation process. Frequency translatio ...

642 SIGNAL PROCESSING Am cos 2πfmt t Signal cos 2πfct t Carrier wave Am cos 2πfmt × cos 2πfct Product 0 f Am fm 1 0 f fm fc 0 f ...

14.2 MODULATION, SAMPLING, AND MULTIPLEXING 643 0 W 2 fc (b) f y(t) cos 2πfct Oscillator Synch Low-pass filter (a) xc(t) z(t) Fi ...

644 SIGNAL PROCESSING x(t) xs(t) xs(t) xs(t) x(t) x(t) s(t) s(t) fs (a) (b) t −Ts Ts D 2 T s^3 Ts 0 t −Ts Ts D 0 2 Ts 3 Ts 1 Fig ...

14.2 MODULATION, SAMPLING, AND MULTIPLEXING 645 0 W fs − W fs fs + W 2 fs (b) (a) f 0 W f Amplitude Amplitude Am a 0 Am a 1 Am/ ...

646 SIGNAL PROCESSING x(t) (a) (b) x(t) t PA M t 0 Ts 2 Ts 3 Ts 4 Ts 5 Ts Ts 2 Ts 3 Ts 4 Ts 5 Ts 0 PDM t 0 PPM t 0 Low-pass filt ...

14.2 MODULATION, SAMPLING, AND MULTIPLEXING 647 t= 0 , 1 40 , 2 40 , ... corresponding toTs= 1 /( 2 W)andfs< 2 W, a smooth cu ...

648 SIGNAL PROCESSING x 1 (t) x 2 (t) x 3 (t) x 1 (t) x 2 (t) x 3 (t) Master oscillator Frequency synthesizer Transmission mediu ...

14.3 INTERFERENCE AND NOISE 649 x 1 x 2 x 3 x 1 x 1 s x 2 x 2 s x 3 x 3 s fs fs Transmission medium Input signals (a) (b) Output ...

650 SIGNAL PROCESSING layer of special magnetic shielding material may become necessary sometimes in extreme cases of magnetic-c ...

14.3 INTERFERENCE AND NOISE 651 Amplitude spectrum Signal Interference f f 0 (a) 0 |H(f)| f f 0 (a) 0 Figure 14.3.2(a) Composite ...

652 SIGNAL PROCESSING receiver of the communication system, or from interference encountered in transmission as in the case of r ...

14.3 INTERFERENCE AND NOISE 653 (a) illustrates a typical thermal noise waveformn(t). In view of the unpredictable behavior, sin ...