|
EDA365欢迎您!
您需要 登录 才可以下载或查看,没有帐号?注册
x
Digital signal processing (DSP) refers to anything that can be done to a! T4 d& T, [! g: y( M* y
signal using code on a computer or DSP chip. To reduce certain( ]: c. l! ^$ u) K; ^: ^
sinusoidal frequency components in a signal in amplitude, digital filtering
; ^0 M/ U5 S x$ U- Jis done. One may want to obtain the integral of a signal. If the signal x3 D& w, h) g: Z& X; K% C T. E
comes from a tachometer, the integral gives the position. If the signal is
0 t Y0 A/ ?6 J2 j: t5 {noisy, then filtering the signal to reduce the amplitudes of the noise$ F3 e* l! k+ d+ j: h) }; N
frequencies improves signal quality. For example, noise may occur from% |) i( e. I- b7 L+ x) g7 B
wind or rain at an outdoor music presentation. F iltering out sinusoidal
8 B& r; M5 [* I/ S/ h' |1 p) ]3 \components of the signal that occur at frequencies that cannot be
) F) Y3 {! o/ @1 Cproduced by the music itself results in recording the music with little wind/ e/ p% a+ l8 S' H7 K
and rain noise. Sometimes the signal is corrupted not by noise, but by4 ]( t: R( k! c* N5 a
other signal frequencies that are of no present interest. If the signal is an
) ^+ \7 R3 O: ?: a# yelectronic measurement of a brain wave obtained by using probes applied
+ n9 e1 r6 m/ r- H- T+ texternally to the head, other electronic signals are picked up by the5 R6 b8 O) I1 C2 h& j- i" g
probes, but the physician may be interested only in signals occurring at a2 S1 G' l8 l- m$ Q; r; F
particular frequency. By using digital filtering, the signals of interest only6 A6 ?8 i1 w2 C! W. |1 J3 q% W
can be presented to the physician. |
|