标题: Digital signal processing [打印本页] 作者: Pang8343569 时间: 2016-11-3 14:13 标题: Digital signal processing Digital signal processing (DSP) refers to anything that can be done to a - c# _4 d: B1 v# Y8 H- O; Ysignal using code on a computer or DSP chip. To reduce certain, k0 k3 E( U% F- p8 |
sinusoidal frequency components in a signal in amplitude, digital filtering # o7 t( R1 b( \1 f; b' c3 B5 d8 qis done. One may want to obtain the integral of a signal. If the signal, H! j" ]) ~1 M0 [; V
comes from a tachometer, the integral gives the position. If the signal is 4 Z5 y& L6 k }noisy, then filtering the signal to reduce the amplitudes of the noise ' o6 m, X, P, h( C1 J" Jfrequencies improves signal quality. For example, noise may occur from* b q# O( k* n2 {6 {
wind or rain at an outdoor music presentation. F iltering out sinusoidal % p& s% ?$ S/ Kcomponents of the signal that occur at frequencies that cannot be/ J" j% o+ F. o* V. ?( c+ f1 t! i
produced by the music itself results in recording the music with little wind2 r. q: `* D( G4 \5 m* ]
and rain noise. Sometimes the signal is corrupted not by noise, but by; K" B0 @* X; H/ c6 T/ N# t# \
other signal frequencies that are of no present interest. If the signal is an. y" C& W4 W1 p" o( K" L4 L/ x* N
electronic measurement of a brain wave obtained by using probes applied, l+ O1 O: q; b5 @0 Z/ l
externally to the head, other electronic signals are picked up by the / J5 K# c/ q% Q- n Iprobes, but the physician may be interested only in signals occurring at a2 t7 h0 L3 W: f
particular frequency. By using digital filtering, the signals of interest only$ r; W8 v" P4 r5 A9 z5 n- x( i
can be presented to the physician.
