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Unformatted text preview: s > 1¬ Ð* ª ´ 7Õ Î 1.4 ¡"@ 1.4.1ª µ3 *8 È 1s s x1 (t ) x2 (t ) x1 (t ) + x2 (t ) shi9876@hzcnc.com 1 s > 1¬ ð* ª µ 7Õ Î 2s s x1 (t ) x2 (tª )ξ µ É x1 (t ) x2 (t ) x1 (t ) + x2 (t ) shi9876@hzcnc.com 2 s > 1¬ H* ª ¼ 7Õ Î 3 s ª ÈÈ *µ x(tª )∪ ȵ dx(t ) dt ∫ t −∞ x(τ )dτ x(t ) = u (t − 1) − u (t − 2) dx(t ) dt = δ (t − 1) − δ (t − 2) 0 t ∫−∞ x(τ )dτ = t − 1 1 t <1 1< t < 2 t>2 shi9876@hzcnc.com 3 s > 1¬ H* ª ´ 7Õ Î s x1 (t )s x2 (tª )(ŵ dx1 (t ) dt s dx2 (t ) dt x1 (t ) = u (t + 1) + u (t ) + u (t − 1) − 3u (t − 2) dx1 (t ) = δ (t + 1) + δ (t ) dt + δ (t − 1) − 3δ (t − 2) shi9876@hzcnc.com 4 s > 1¬ À* ª µ 7Õ Î x2 (t ) = −t [ u (t + 1) − u (t )] + t [ u (t ) − u (t − 1)] dx2 (t ) = −[ u (t + 1) − u (t )] − t [δ (t + 1) − δ (t )] dt + [ u (t ) − u (t − 1)] + t [δ (t ) − δ (t − 1)] = −[ u (t + 1) − u (t )] + δ (t + 1) + [ u (t ) − u (t − 1)] − δ (t − 1) shi9876@hzcnc.com 5 s > 1¬ ˆÕ * ª µ 7 Î äÀ δ ' (t ) ∆→0 ∆→0 shi9876@hzcnc.com 6 s > 1¬ 0* ª ¼ 7Õ Î 1.4.2ª µ3 *h Á 1 s3 h ªµÁ t0 > 0 x(t ) → x(t − t0 ) x(t ) → x(t + t0 ) shi9876@hzcnc.com 7 s > 1¬ ¨Õ * ª µ 7 Î 2 s ª (Å µ 3 s (Å3 µª* (1) s s a >1 shi9876@hzcnc.com 3Å (µª* x(t ) → x(at ) 8 s > 1¬ 0* ª ¼ 7Õ Î 0 < a <1 x(t ) → x(at ) 1 δ (at ) = δ (t ) a a>0 1∞ 1 ∫−∞ δ (at )dt = a ∫−∞ δ (τ )dτ = a ∞ shi9876@hzcnc.com 9 s > 1¬ ø* ª µ 7Õ Î x x(t )ĵª x(2t ) 1 3 12 δ (t − 3) → δ (2t − 3) = δ t − 2 2 (2) s ~W 'µª*ЩÛD y[n] = x[kn] y[n] = x[2n] y[n] = x[3n] shi9876@hzcnc.com 10 s > 1¬ à* ª ¼ 7Õ Î s s n x[k ] n = kN y[n] = x = = x( N ) [ n] n ≠ kN N 0 n x[k ] n = 2k = x( 2 ) [ n] y[n] = x = n ≠ 2k 2 0 shi9876@hzcnc.com 11 s > 1¬ È* ª ¼ 7Õ Î x[ n 2 ] n = 2 k x( 2 ) [ n ] = n ≠ 2k 0 x(t ) x x ( −t ) s s 2 2 x(−(t − 2)) = x(2 − t ) x(−(t + 2)) = x(−t − 2) shi9876@hzcnc.com 12 s > 1¬ (Õ * ª ¼ 7 Î s x(t ) s 12 x(2t ) s 2 s x(t ) s 2 2 x x(t − 2) s x x x(2(t − 2)) = x(2t − 4) x(2(t + 2)) = x(2t + 4) x(−t − 2) 12 x(2t − 2) x* (tª )y µ x(3t + 6)x x(−3t + 6) shi9876@hzcnc.com 13 s > 1¬ ¸Õ * ª µ 7 Î x(t ) s x(−3t + 6) 6 x x(t + 6) x(3t + 6) shi9876@hzcnc.com 14 s > 1¬ •Õ * ª ¼ 7 Î 1.5 ª è µÉ 3 1.5.1ª µ3 É è vs (t ) vc (t ) vs (t ) = vR (t ) + vc (t ) = Ri (t ) + vc (t ) i (t ) = C dvc (t ) dt RC dvc (t ) + vc (t ) = vs (t ) dt á•T½* shi9876@hzcnc.com 15 s > 1¬ •Õ * ª ¼ 7 Î x[n] ~ %Ø n%Ø y[n] ~ ª 1à µ h n x[n] y[n] y[n] = 1.01 y[n − 1] + x[n] y[n] − 1.01y[n − 1] = x[n] * ½ (T • á *ªη õ y[n] = y zs [n] + y zi [n] y zs [n] % Ø y zi [n] % Ø 0Ø 0% Ø shi9876@hzcnc.com x 16 s > 1¬ è* ª ¼ 7Õ Î y[n] ~ nˆ y[1] ~ s 1 ˆ y[2] ~ x 2 ˆ y[0] å ˆ x ~x y[0] ≠ 0 å ˆ x ˆ x[n] = 0x y zi [n]x 0♦ ªµ È3 åˆ x[n] ªµ È3 ♦ åˆ x y[0] ≠ 0x nx n y zs [n] x[n]x shi9876@hzcnc.com y[n] = y zs [n] + y zi [n]x 17 s > 1¬ 0* ª ¼ 7Õ Î 1.5.2ª µ3 Å ( 1 s3 ( * ªµÅ 2s s shi9876@hzcnc.com 18 s > 1¬ è* ª ¼ 7Õ Î 3s s shi9876@hzcnc.com 19 ...
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This note was uploaded on 08/22/2011 for the course EE 201 taught by Professor Yhm during the Spring '05 term at Zhejiang University.

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