1[size=1em]测量信号幅度时的单位及其定义为:
l$ w0 `8 ~3 {( s3 t- d+ ]
单位 | | | V | | | Vrms | | | Vp | | | Vpp | | | dBV | | | dBu | | | dBm | (毫瓦分贝)以600Ώ1mW为零电平的分贝 | | dBg | | | dBr | | | dBrinv | | | W | | |
, K, |- U9 \. J- q) ^1 |9 @% Z0 g, c$ z0 L
2[size=1em]相对量的单位: C1 j& ~! m1 |& d9 I
+ K2 ?8 t6 s6 R1 b `
功能 | | | THD+N Ratio | | | THD+N Ratio | | 20*lg[(噪声+失真)/(信号+噪声+失真)] | 2-Channel Ratio | | ChA=20*lg(A/B) , ChB=20*lg(B/A) | 2-Channel Ratio | | ChA=100*(A/B) , ChB=100*(B/A) | Crosstalk | | | S/N Ratio | | 20*lg((信号+失真+噪声)/(失真+噪声)) |
& b% C( S3 d+ T7 M3[size=1em]频率单位$ ]0 `+ B' g& \- l
$ R1 D4 e' r% c9 L0 o {% k- D) g4 s
单位 | | Hz | | F/R | | dHz | | Cent | | Octaves | | Decades | | %Hz | | d% | | MdPPM | | PPM | |
% J* m0 n4 m7 K m7 }5 P3 I模拟信号分析仪
+ z4 ]/ J# |, O! p/ g/ P
: J6 w; @( I6 {% c. ~1[size=1em]各测试功能的选择:
* A- F5 e( j- Y+ k' YAmplitude | | Bandpass | | Bandreject | | THD+N Ampl | | THD+N Ratio | | SMPTE/DIN | | CCIF | | DIM/TIM | | Wow&Flutter | | 2-Ch Ratio | | Crosstalk | | DFD | 失真(总谐波失真+噪音)测试(以比率形式表示)
1 ?" e2 H' s. S6 ^
|
: |5 ]2 }+ K" `% p0 W |